View Filing Data

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2015	Mar. 25, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	WVE
Entity Registrant Name	WAVE LIFE SCIENCES LTD.
Entity Central Index Key	0001631574
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		21,551,423
Entity Public Float	$ 0

Consolidated Balance Sheets - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash	$ 161,220,000	$ 1,048,000
Accounts receivable		200,000
Prepaid expenses and other current assets	146,000	103,000
Deferred tax assets	18,000	64,000
Deferred offering costs	0	72,000
Total current assets	161,384,000	1,487,000
Property and equipment, net	2,789,000	1,269,000
Deferred tax assets	192,000	182,000
Restricted cash	1,055,000	0
Other assets	4,000
Total assets	165,424,000	2,938,000
Current Liabilities:
Accounts payable	2,811,000	125,000
Accrued expenses and other current liabilities	945,000	605,000
Deferred revenue		152,000
Current portion of capital lease obligation	62,000
Total current liabilities	3,818,000	882,000
Long-term liabilities:
Capital lease obligation, net of current portion	78,000
Other liabilities	163,000	29,000
Total long-term liabilities	241,000	29,000
Total liabilities	4,059,000	911,000
Shareholders' equity:
Series A preferred shares, no par value; 3,901,348 shares issued and outstanding at December 31, 2014		7,874,000
Ordinary shares, no par value; 21,551,423 and 4,263,472 shares issued and outstanding at December 31, 2015 and 2014, respectively	185,344,000	9,973,000
Additional paid-in capital	3,182,000
Accumulated other comprehensive income	41,000	56,000
Accumulated deficit	(35,076,000)	(15,876,000)
Total shareholders' equity	153,491,000	2,027,000
Total liabilities, Series A preferred shares, and shareholders' equity	165,424,000	2,938,000
Series A Preferred Shares [Member]
Long-term liabilities:
Preferred stock value	$ 7,874,000
Shareholders' equity:
Total shareholders' equity		$ 7,874,000

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Preferred stock, par value
Preferred stock, shares issued		3,901,348
Preferred stock, shares outstanding		3,901,348
Common stock, par value
Common stock, shares issued	21,551,423	4,263,472
Common stock, shares outstanding	21,551,423	4,263,472
Series A Preferred Shares [Member]
Preferred stock, par value	$ 0
Preferred stock, shares issued	3,901,348
Preferred stock, shares outstanding	3,901,348

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenue	$ 152
Operating expenses:
Research and development	9,057	$ 2,395	$ 1,920
General and administrative	10,393	2,999	1,654
Total operating expenses	19,450	5,394	3,574
Loss from operations	(19,298)	(5,394)	(3,574)
Other income (expense):
Interest income (expense), net	86	(12)	(111)
Other, net	56	261	37
Total other income (expense)	142	249	(74)
Loss before income tax (provision) benefit	(19,156)	(5,145)	(3,648)
Income tax (provision) benefit	(44)	(84)	330
Net loss	$ (19,200)	$ (5,229)	$ (3,318)
Net loss per share attributable to ordinary shareholders-basic and diluted	$ (1.83)	$ (1.34)	$ (1.90)
Weighted-average ordinary shares used in computing net loss per share attributable to ordinary shareholders-basic and diluted	10,501,455	3,911,556	1,743,014

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net loss	$ (19,200)	$ (5,229)	$ (3,318)
Other comprehensive income (loss)
Foreign currency translation	(15)	(169)	135
Comprehensive loss	$ (19,215)	$ (5,398)	$ (3,183)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Consolidated Statement of Series A Preferred Shares and Shareholders' (Deficit) Equity - USD ($) $ in Thousands	Total	Ordinary Shares [Member]	Additional Paid-In-Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]	IPO [Member]	IPO [Member] Ordinary Shares [Member]	Series A Preferred Shares [Member]	Series B Preferred Shares [Member]
Beginning balance at Dec. 31, 2012	$ (4,579)	$ 2,660		$ 90	$ (7,329)
Beginning balance, shares at Dec. 31, 2012		2,020,794
Conversion of ordinary shares to Series A preferred shares		$ (2,022)						$ 2,022
Conversion of ordinary shares to Series A preferred shares, shares		(1,536,209)						1,536,209
Other comprehensive income	135			135
Net loss	(3,318)				(3,318)
Ending balance at Dec. 31, 2013	(7,762)	$ 638		225	(10,647)			$ 2,022
Ending balance, shares at Dec. 31, 2013		484,585						1,536,209
Conversion of related party notes payable to ordinary shares and Series A preferred shares	9,602	$ 3,750						$ 5,852
Conversion of related party notes payable to ordinary shares and Series A preferred shares, shares		1,515,596						2,365,139
Issuance of ordinary shares upon initial public offering, net of issuance costs	5,585	$ 5,585
Issuance of ordinary shares upon initial public offering, net of issuance costs, shares		2,263,291
Other comprehensive income	(169)			(169)
Net loss	(5,229)				(5,229)
Ending balance at Dec. 31, 2014	2,027	$ 9,973		56	(15,876)			$ 7,874
Ending balance, shares at Dec. 31, 2014		4,263,472						3,901,348
Temporary equity, Issuance of Series B preferred									$ 62,532
Issuance of ordinary shares upon initial public offering, net of issuance costs	11,631	$ 11,631				$ 100,366	$ 100,366
Temporary equity, Issuance of Series B preferred, shares									5,334,892
Issuance of ordinary shares upon initial public offering, net of issuance costs, shares		4,769,077					6,993,126
Temporary equity, Reclassification of Series A preferred shares								$ 7,874
Stock-based compensation	4,024	$ 842	$ 3,182
Temporary equity, Reclassification of Series A preferred shares, shares								3,901,348
Stock-based compensation, shares		190,856
Temporary equity, Conversion of Series B preferred shares into ordinary shares upon initial public offering									$ (62,532)
Reclassification of Series A preferred shares	(7,874)							$ (7,874)
Temporary equity, Conversion of Series B preferred shares into ordinary shares upon initial public, shares									(5,334,892)
Reclassification of Series A preferred shares, shares								(3,901,348)
Temporary equity, Ending balance at Dec. 31, 2015								$ 7,874
Conversion of Series B preferred shares into ordinary shares upon initial public offering	62,532	$ 62,532
Temporary equity, Ending balance, shares at Dec. 31, 2015								3,901,348
Conversion of Series B preferred shares into ordinary shares upon initial public offering, shares		5,334,892
Other comprehensive income	(15)			(15)
Net loss	(19,200)				(19,200)
Ending balance at Dec. 31, 2015	$ 153,491	$ 185,344	$ 3,182	$ 41	$ (35,076)
Ending balance, shares at Dec. 31, 2015		21,551,423

Consolidated Statement of Series A Preferred Shares and Shareholders' (Deficit) Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Net of issuance costs		$ 15
Ordinary Shares [Member]
Net of issuance costs	$ 169
Series B Preferred Shares [Member]
Net of issuance costs	3,468
IPO [Member] \| Ordinary Shares [Member]
Issuance of common stock, issuance costs	$ 3,702

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net loss	$ (19,200)	$ (5,229)	$ (3,318)
Adjustments to reconcile net loss to net cash flows used in operating activities:
Depreciation and amortization	594	281	276
Share-based compensation expense	4,024
Deferred rent	88	(6)	(6)
Loss on disposal of property and equipment		14
Deferred income taxes	36	84	(330)
Changes in operating assets and liabilities:
Accounts receivable	193	(129)	(102)
Prepaid expenses and other current assets	(63)	(12)	3
Accounts payable	1,648	9	(152)
Accrued expenses and other current liabilities	267	410	78
Deferred revenue	(152)	152
Other non-current liabilities	38
Net cash used in operating activities	(12,527)	(4,426)	(3,551)
Cash flows from investing activities
Increase in restricted cash	(1,055)
Proceeds from government grant reimbursements for property and equipment	3	319
Proceeds from sale of property and equipment		14
Purchase of property and equipment	(1,857)	(590)	(47)
Net cash used in investing activities	(2,909)	(257)	(47)
Cash flows from financing activities
Proceeds from initial public offering, net of offering costs and underwriter commissions	101,444
Proceeds from issuance of Series B preferred shares, net of offering costs	62,532
Proceeds from issuance of ordinary shares, net of offering costs	11,631	5,585
Proceeds from government grant	112	34
Proceeds from related party notes payable			6,172
Payment of related party notes payable			(2,500)
Payments on capital lease obligation	(126)
Net cash provided by financing activities	175,593	5,619	3,672
Effect of foreign exchange rates on cash	15	(327)	(14)
Net increase in cash	160,172	609	60
Cash at beginning of period	1,048	439	379
Cash at end of period	161,220	1,048	439
Supplemental disclosure of cash flow information:
Conversion of related party notes payable into ordinary and Series A preferred shares		9,602
Cash paid for interest		86	90
Equipment under acquired for capital lease obligation	268
Conversion of ordinary shares into Series A preferred shares			2,022
Property and equipment purchases in accounts payable	306	3	$ 50
Increase in accrued expenses for deferred offering costs	$ 1,075	$ 72

The Company	12 Months Ended
The Company	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	1. THE COMPANY *Organization* WAVE Life Sciences Ltd. (together with its subsidiaries, “WAVE” or the “Company”) is a preclinical biopharmaceutical company with a proprietary synthetic chemistry drug development platform that the Company is using to design, develop and commercialize a broad pipeline of first-in-class or best-in-class nucleic acid therapeutic candidates. The Company is initially developing nucleic acid therapeutics that target genetic defects to either reduce the expression of disease-promoting proteins or transform the production of dysfunctional mutant proteins into the production of functional proteins. The Company was incorporated in Singapore on July 23, 2012 and has its principal office in Cambridge Massachusetts. The Company was incorporated with the purpose of combining two commonly held companies, WAVE Life Sciences USA, Inc. (“WAVE USA”), a Delaware corporation (formerly Ontorii, Inc.), and WAVE Life Sciences (Japan) (“WAVE Japan”), a company organized under the laws of Japan (formerly Chiralgen., Ltd.), which occurred on September 12, 2012. The Company was created through the combination of entities that were under the common control of Shin Nippon Biomedical Laboratories Ltd. (“SNBL”) both prior to and immediately following the Company’s incorporation. Since the entities represent the combination of entities under common control, generally accepted accounting principles in the United States (“U.S. GAAP”) require the presentation of the combined companies as if they have always been combined entities. Therefore, on the date of incorporation, the Company recognized the assets and liabilities of WAVE USA and WAVE Japan at the carrying amounts of the assets and liabilities as recorded in the standalone financial statements of the respective companies on that date. On November 5, 2015, the Company converted from a Singapore private limited company to a Singapore public limited company. In connection with this conversion, the Company changed its name from WAVE Life Sciences Pte. Ltd. to WAVE Life Sciences Ltd. The Company’s primary activities since inception have been conducting research and experimental development of biotechnology and chemicals, conducting preclinical testing, recruiting personnel, and raising capital to support development activities. *Initial Public Offering* On November 16, 2015, the Company closed an initial public offering of its ordinary shares, in which the Company issued and sold 6,375,000 ordinary shares at a price to the public of $16.00 per share. On December 4, 2015, the Company issued an additional 618,126 ordinary shares at a price of $16.00 per share pursuant to a partial exercise of the underwriters’ over-allotment option. The aggregate net proceeds to the Company from the initial public offering, inclusive of the over-allotment exercise, were $100,366 after deducting underwriting discounts and commissions and offering expenses payable by the Company. Upon the listing of the Company’s ordinary shares on the NASDAQ Global Market on November 11, 2015, all of the outstanding Series B preferred shares of the Company automatically converted into 5,334,892 of the Company’s ordinary shares. *Risks and Uncertainties* The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. The Company’s therapeutic programs will require significant additional research and development efforts, including extensive pre-clinical and clinical testing and regulatory approval, prior to commercialization of any product candidates. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance-reporting capabilities. The Company’s therapeutic programs are currently in the development or discovery stage. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees and consultants. *Basis of Presentation* The Company has prepared the accompanying consolidated financial statements in conformity with U.S. GAAP and in U.S. dollars.

Significant Accounting Policies

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Significant Accounting Policies

2. SIGNIFICANT ACCOUNTING POLICIES

Share Splits

The Company’s board of directors and shareholders approved a 50-for-1 share split of the Company’s outstanding ordinary and Series A preferred shares effective November 18, 2014. Additionally, on November 1, 2015, the Company’s board of directors and shareholders approved a 4.0415917-for-1 share split of the Company’s issued and outstanding ordinary shares, Series A preferred shares and Series B preferred shares. All share and per share amounts in the consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to give effect to the share splits.

Principles of Consolidation

The Company’s consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include the valuation of its Series A preferred shares on conversion of the related party notes payable, the valuation of the Company’s ordinary shares prior to the initial public offering, the assumptions used to determine the fair value of share-based awards, the valuation allowance required for the Company’s deferred tax assets, and determining uncertain tax positions and the related liabilities. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results could differ from the Company’s estimates.

Segment Data

The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is on developing its proprietary synthetic chemistry platform to develop and commercialize a broad pipeline of nucleic acid-based therapeutics.

Foreign Currency Translation

The functional currency of the Company’s Japanese subsidiary is the Japanese Yen and the Company’s Singapore entity is the U.S. dollar. Assets and liabilities of WAVE Japan are translated at period end exchange rates while revenues and expenses are translated at average exchange rates for the period. Intercompany loans that are not expected to be settled in the foreseeable future are translated at the historical rate for the date of each capital transaction. Net unrealized gains and losses from foreign currency translation are reflected as accumulated other comprehensive (loss) income within Series A preferred shares and shareholders’ (deficit) equity. Gains and losses on foreign currency transactions are included in the consolidated statements of operations within other, net.

Fair Value of Financial Instruments

The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. The fair value hierarchy is a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the financial instrument based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the financial instrument and are developed based on the information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The hierarchy defines three levels of valuation inputs:

Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date of identical, unrestricted assets.

Level 2—Quoted prices for similar assets, or inputs that are observable, either directly or indirectly, for substantially the full term through corroboration with observable market data. Level 2 includes investments valued at quoted prices adjusted for legal or contractual restrictions specific to the security.

Level 3—Pricing inputs are unobservable for the asset, that is, inputs that reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset. Level 3 includes private investments that are supported by little or no market activity.

There were no financial instruments recorded at fair value as of December 31, 2015 and 2014. The carrying amounts of accounts receivable, accounts payable, and accrued expenses approximate their fair values due to their short-term maturities.

Concentration of Credit Risk

Cash is a financial instrument that potentially subjects the Company to concentration of credit risk. The Company uses eight financial institutions to maintain its cash, all of which are high quality, accredited financial institutions and, accordingly, such funds are subject to minimal credit risk. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held. The Company has no financial instruments with off-balance sheet risk of loss.

Restricted Cash

Restricted cash consists primarily of cash placed in a separate restricted bank account as required under the terms of the Company’s lease arrangement for its Cambridge, Massachusetts facility. There was no restricted cash as of December 31, 2014 and 2013.

Property and Equipment

Property and equipment, which consists of furniture and equipment and leasehold improvements are stated at cost less accumulated depreciation and amortization. Depreciation is calculated on a straight-line basis over the following estimated useful lives of the assets:


Furniture and Equipment		3-7 years
Leasehold Improvements		Shorter of life of lease or useful life

Depreciation and amortization begins at the time the asset is placed in service. Maintenance and repairs are charged to operations as incurred. Upon retirement or sale, the cost of the disposed asset and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in the consolidated statements of operations.

Impairment of Long-Lived Assets

Long-lived assets consist of property and equipment. Long-lived assets are reviewed for impairment whenever events or other changes in circumstances indicate that the carrying amount may not be recoverable. Certain factors may exist or events may occur, which indicate that impairment exists including, but not limited to, the following: significant underperformance relative to historical or projected future operating results; significant changes in the manner of use of the underlying assets; and significant adverse industry or market economic trends.

When performing the impairment assessment for long-lived assets, the Company compares the carrying value of such assets to the estimated undiscounted future net cash flows expected from the use of the assets and their eventual disposition. In the event that the carrying value of the assets is determined to be unrecoverable, the Company would estimate the fair value of the assets and record an impairment charge for the excess of the carrying value over the fair value.

Through December 31, 2015, the Company has not recognized any impairment charges.

Deferred Offering Costs

The Company capitalizes certain legal, professional, accounting and other third party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of the equity financing, these costs are recorded in shareholders’ equity as a reduction to the carrying value of the shares issued.

At December 31, 2014 the Company had recorded $72 of deferred offering costs in contemplation of the private offering of ordinary shares, which were reclassified to additional paid in capital as a reduction of the proceeds from the private offering. There were no deferred offering costs at December 31, 2015.

Revenue Recognition

Collaboration Agreement

The Company had a collaboration agreement with a third party, which was entered into in late 2014 and terminated in May 2015. The Company was entitled to a non-refundable upfront amount of $152 related to research and development services performed under the agreement. The upfront fee was billed in 2014 and collected in early 2015. The Company recorded its right to the upfront payment as accounts receivable and deferred revenue at December 31, 2014. Upon receipt of the non-refundable payment, the Company began recognizing the upfront fee on a straight-line basis over the service period. Upon termination of the agreement, the Company recognized the remainder of the upfront fee. Revenue recognized under the agreement was $152 for the year ended December 31, 2015 and $0 for each of the years ended December 31, 2014 and 2013. There have been no other revenue generating activities from collaboration or license agreements entered into by the Company since its formation.

Product Revenue

The Company has had no product revenue to date.

Allowance for Doubtful Accounts

The Company has a limited amount of accounts receivable, which relate primarily to reimbursement of qualified expenditures under a government grant. The Company has not had any bad debts from the date of incorporation through December 31, 2015. All amounts recorded as accounts receivable have been collected to date.

Research and Development Costs

Research and development costs are expensed as incurred. Research and development costs include salaries, share-based compensation and benefits of employees, third-party license fees and other operational costs related to the Company’s research and development activities, including allocated facility-related expenses and external costs of outside vendors engaged to conduct preclinical studies and other research and development activities. Costs associated with licenses of technology and patent costs are expensed as incurred and are generally included in research and development expense in the consolidated statement of operations.

Government Grants

The Company has applied for reimbursement of expenditures with the Japanese government for certain qualified operating or capital expenditures. The Company recognizes government grants when there is reasonable assurance that the Company will comply with the conditions attached to the grant arrangement and the grant will be received.

Government grants for research and development efforts are recorded as grant income and classified in other, net in the consolidated statements of operations. Government grants related to reimbursements of capital expenditures are recognized as a reduction of the basis of the asset and recognized in the consolidated statements of operations over the estimated useful life of the depreciable asset as reduced depreciation expense.

The Company recognized other income of $155, $160 and $43 for the years ended December 31, 2015, 2014 and 2013, respectively, which is included in the consolidated statements of operations.

The Company recorded reimbursable capital expenditures of $3, $248 and $66 for the years ended December 31, 2015, 2014 and 2013, respectively, for which a reduction in the basis of the assets purchased was recorded in the consolidated balance sheets.

Net Loss per Share

Basic net loss per share is computed using the weighted-average number of ordinary shares outstanding during the period. Diluted net loss per share is computed using the sum of the weighted-average number of ordinary shares outstanding during the period and, if dilutive, the weighted-average number of potential ordinary shares, including the assumed exercise of share options.

The Company applies the two-class method to calculate its basic and diluted net loss per share attributable to ordinary shareholders, as its Series A preferred shares are participating securities. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to ordinary shareholders. However, for the periods presented, the two-class method does not impact the net loss per ordinary share as the Company was in a net loss position for each of the periods presented and holders of Series A preferred shares do not participate in losses.

The Company’s Series A preferred shares contractually entitle the holders of such shares to participate in dividends but do not contractually require the holders of such shares to participate in losses of the Company. Accordingly, for periods in which the Company reports a net loss attributable to ordinary shareholders, diluted net loss per share attributable to ordinary shareholders is the same as basic net loss per share attributable to ordinary shareholders, since dilutive ordinary shares are not assumed to have been issued if their effect is anti-dilutive.

License Agreements and Patent Costs

Costs associated with licenses of technology and patent costs are expensed as incurred and are generally included in research and development expense in the consolidated statements of operations.

Share-Based Compensation

The Company measures and recognizes share-based compensation expense, for both employee and director option awards, based on the grant date fair value of the awards. The Company recognizes share-based compensation expense, net of estimated forfeitures, on a straight-line basis over the requisite service period of the awards, which is generally the vesting period.

The Company determines the fair value of share-based awards granted to non-employees as either the fair value of the consideration received or the fair value of the equity instruments issued, whichever is more reliably measurable. All issuances of equity instruments issued to non-employees as consideration for goods or services received by the Company are accounted for based on the fair value of the equity instruments issued. These awards are recorded in expense and additional paid-in capital in shareholders’ equity over the applicable service periods based on the fair value of the options at the end of each period.

The Company classifies share-based compensation expense in its consolidated statements of operations in the same manner in which the award recipient’s payroll costs are classified or in which the award recipients’ service payments are classified.

The Company estimates the fair value of employee and director share options as of the date of grant using the Black- Scholes option pricing model. The Company historically has been a private company and lacks company-specific historical and implied volatility information. Therefore, it estimates its expected share volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded share price. The expected term of the Company’s share options has been determined utilizing the “simplified” method for awards that qualify as “plain- vanilla” options. The risk-free interest rate is determined by reference to the yield curve of a zero-coupon U.S. Treasury bond on the date of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends on ordinary shares and does not expect to pay any cash dividends in the foreseeable future.

The Company also estimates the fair value of consultant and non-employee share options using the Black-Scholes option pricing model reflecting the same assumptions as applied to employee and director options in each of the reporting periods, other than the expected life, which is assumed to be the remaining contractual life of the options.

Income Taxes

The Company accounts for income taxes using an asset and liability approach, which requires recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements, but have not been reflected in taxable income. A valuation allowance is established to reduce deferred tax assets to their estimated realizable value. Therefore, the Company provides a valuation allowance to the extent that it is more likely than not that all or a portion of the deferred tax assets will not be realized in the future.

The Company accounts for uncertainty in income taxes recognized in the financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties.

The Company recognizes interest and penalties related to uncertain tax positions in the income tax provision on the consolidated statements of operations.

The Company has certain service arrangements in place between our U.S and Singapore entities, which include transfer pricing assumptions. The determination of the appropriate level of transfer pricing requires judgment based on transfer pricing analyses of comparable companies. The Company monitors the nature of their service arrangements for changes in our operations as well as economic conditions. The Company also periodically reviews the transfer pricing analyses for changes in the composition in the pool of comparable companies as well the related ongoing results of the comparable companies.

Recently Adopted Accounting Pronouncements

In July 2013, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (“ASU 2013-11”), which requires unrecognized tax benefits to be presented as a decrease in a net operating loss, similar tax loss or tax credit carryforward if certain criteria are met. The guidance was effective for fiscal years and interim periods within those years beginning after December 15, 2013 for public entities with early adoption permitted in 2013. The Company elected to early adopt ASU 2013-11 in 2013.

In June 2014, the FASB issued ASU 2014-10, Development Stage Entities. The amendments in this update removed all incremental financial reporting requirements, including inception-to-date information and certain other disclosures currently required under U.S. GAAP, in the financial statements of development stage companies. The amendments are effective for annual reporting periods beginning after December 15, 2014 and interim reporting periods beginning after December 15, 2015. Early adoption is permitted for any annual reporting period or interim period for which the entity’s financial statements have not yet been issued (public business entities) or made available for issuance (other entities). The Company elected to early adopt this guidance in 2014 and, therefore, has not presented inception-to-date disclosures in its consolidated financial statements.

Recently Issued Accounting Pronouncements

In May 2014, the FASB issued ASU 2014-09—Revenue from Contracts with Customers (Topic 606) (“ASU 2014-09”). ASU 2014-09 supersedes most of the existing guidance on revenue recognition in ASC Topic 605, Revenue Recognition. The core principle of the revenue model is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. In applying the revenue model to contracts within its scope, an entity will need to (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract and (v) recognize revenue when (or as) the entity satisfies a performance obligation. On July 9, 2015, the FASB extended the effective date of adoption of the standard to interim reporting periods within annual reporting periods beginning after December 15, 2017 (that is, beginning in the first interim period within the year of adoption). Early adoption of the standard is permitted for all entities for interim and annual periods beginning after December 15, 2016. The Company has not yet determined the impact of ASU 2014-09 on expected revenues.

In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements—Going Concern, on disclosure of uncertainties about an entity’s ability to continue as a going concern. This guidance addresses management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and to provide related footnote disclosures. The guidance is effective for fiscal years beginning after December 15, 2016 and for interim periods within those fiscal years, with early adoption permitted. The Company does not expect the adoption of this guidance to have a material impact on the consolidated financial statements.

In February 2015, the FASB issued ASU 2015-02, Consolidation (Topic 810) (“ASU 2015-02”), to address financial reporting considerations for the evaluation as to the requirement to consolidate certain legal entities. ASU 2015-02 is effective for fiscal years and for interim periods within those fiscal years beginning after December 15, 2015. The Company is evaluating the impact of ASU 2015-02 and if early adoption is appropriate in future reporting periods.

In April 2015, the FASB issued ASU 2015-03, Interest—Imputation of Interest (Subtopic 835-30) (“ASU 2015-03”), as part of the initiative to reduce complexity in accounting standards. The update requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU 2015-03 is effective for annual periods beginning after December 15, 2015 and for interim periods within those fiscal years. The Company does not expect the impact of ASU 2015-03 to be material to its consolidated financial statements.

In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes (“ASU 2015-17”), which requires entities to present deferred tax assets and deferred tax liabilities as noncurrent in a classified balance sheet. The ASU simplifies the current guidance in ASC Topic 740, Income Taxes, which requires entities to separately present deferred tax assets and liabilities as current and noncurrent in a classified balance sheet. ASU 2015-17 is effective for fiscal years beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted for all entities as of the beginning of an interim or annual reporting period. The Company does not expect the impact of ASU 2015-17 to be material to its consolidated financial statements.

In February 2016, the FASB issued ASU 2016-02, Leases, which requires a lessee to recognize assets and liabilities on the balance sheet for operating leases and changes many key definitions, including the definition of a lease. The Update includes a short-term lease exception for leases with a term of 12 months or less, in which a lessee can make an accounting policy election not to recognize lease assets and lease liabilities. Lessees will continue to differentiate between finance leases (previously referred to as capital leases) and operating leases, using classification criteria that are substantially similar to the previous guidance. For lessees, the recognition, measurement, and presentation of expenses and cash flows arising from a lease have not significantly changed from previous GAAP. Lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply as well as transition guidance specific to nonstandard leasing transactions. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. The Company does not expect the impact of ASU 2016-02 to be material to its consolidated financial statements.

Other accounting standards that have been issued or proposed by the FASB or other standards-setting bodies that do not require adoption until a future date are not expected to have a material impact on the Company’s consolidated financial statements upon adoption.

Property and Equipment

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

Property and Equipment

3. PROPERTY AND EQUIPMENT

Property and equipment, net, consists of the following


	December 31,
	2015			2014
Furniture and equipment	$	3,936		$	2,331
Fixed assets in progress		198			—
Leasehold improvements		267			147

Total		4,401			2,478
Less accumulated depreciation and amortization		(1,612	)		(1,209	)

Property and equipment, net	$	2,789		$	1,269

Leasehold improvements made during the year ended December 31, 2015 consisted primarily of costs related to the Company’s newly leased office space in Cambridge, Massachusetts.

Depreciation and amortization expense was $594, $281 and $276 and for the years ended December 31, 2015, 2014 and 2013.

Accrued Expenses

12 Months Ended

Dec. 31, 2015

Payables and Accruals [Abstract]

Accrued Expenses

4. ACCRUED EXPENSES

Accrued expenses and other current liabilities consist of the following:


	December 31,
	2015		2014
Accrued compensation	$	—	$	315
Accrued audit fees		400		—
Accrued vacation		191		113
Other		354		177

Total accrued expenses and other current liabilities	$	945	$	605

Related Party Notes Payable	12 Months Ended
Related Party Notes Payable	Dec. 31, 2015
Text Block [Abstract]
Related Party Notes Payable	5. RELATED PARTY NOTES PAYABLE At December 31, 2012, the Company had unsecured loans in the amount of $6,174 payable to SNBL with interest rates which ranged from 1.33% to 1.58% annually, which were due to mature in 2013. In 2013, the Company borrowed an additional $6,172 at similar interest rates, and repaid $2,500 of such loans plus accrued and unpaid interest. Additionally, in 2013, the maturity dates of the remaining loans were extended to dates in 2014 through new loan agreements and a loan between WAVE Japan and SNBL was transferred to WAVE Life Sciences Ltd. in U.S. dollars. At December 31, 2013, the Company had unsecured loans in the amount of $9,602 payable to SNBL with interest rates which ranged from 1.18% to 1.35% annually, which were due to mature in 2014. In February 2014 and in connection with the issuance of 2,263,291 ordinary shares to a third party investor, SNBL agreed to convert the outstanding principal and accrued interest due under the notes payable in the amount of $9,602 into 1,515,596 ordinary shares and 2,365,139 Series A preferred shares. No gain or loss was recognized on the transaction due to the related party nature of the transaction and because the fair value of the Series A preferred shares and ordinary shares was equal to the carrying value of the related party notes payable.

Share Capital

12 Months Ended

Dec. 31, 2015

Equity [Abstract]

Share Capital

6. SHARE CAPITAL

Ordinary Shares

The following represents the historical ordinary share transactions of the Company from its incorporation through December 31, 2015:

•

In September 2012, the Company issued an aggregate of 2,020,794 ordinary shares to the then shareholders of WAVE USA and WAVE Japan, as consideration for the merger of the companies under common control in which the WAVE USA and WAVE Japan historical carrying values of their respective net assets were carried forward to the consolidated Company.

•

In October 2013, the holder of 1,536,209 ordinary shares agreed to convert its holdings into an equivalent number of Series A preferred shares.

•

In February 2014, the Company issued 2,263,291 ordinary shares to a third-party investor at $2.47 per share for net proceeds of $5,585. In connection with this financing, holders of $9,602 of related party notes payable agreed to convert such notes into 2,365,139 Series A preferred shares and 1,515,596 ordinary shares (Note 5).

•

In January 2015, the Company issued 4,769,077 ordinary shares to a third-party investor and an existing investor at $2.47 per share for net proceeds of $11,631.

•

In March 2015, the Company granted 190,856 fully-vested ordinary shares to an executive of the Company.

•

In November 2015, the Company completed an initial public offering of its ordinary shares, in which the Company issued and sold 6,375,000 ordinary shares at a price to the public of $16.00 per share. In December 2015, the Company issued an additional 618,126 ordinary shares at a price of $16.00 per share pursuant to a partial exercise of the underwriters’ over-allotment option. The aggregate net proceeds to the Company from the initial public offering, inclusive of the over-allotment exercise, were $100,366 after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company.

Features of the Ordinary Shares

The ordinary shares have no par value and there is no authorized share capital under Singapore law. The rights, preferences, and privileges of ordinary shares are as follows:

New Share Offering

Any new ordinary shares or securities convertible into ordinary shares shall be offered in the first instance to all the then holders of any class of shares, other than the Series A preferred shares, prior to issuance. Each shareholder shall have right of pre-emption with respect to any issuance of new ordinary shares or securities convertible into ordinary shares. This right of pre-emption shall not apply to shares sold in an initial public offering of the Company’s equity securities and shall terminate immediately prior to the closing of an initial public offering.

Voting

The holders of ordinary shares are entitled to one vote for each ordinary share held at all meetings of shareholders and written actions in lieu of meetings provided; however, that except as otherwise required by law, holders of ordinary shares shall not be entitled to implement the following without the approval of more than 75% of the Company’s issued and outstanding ordinary shares:

(i)

a merger, split, corporate reorganization, liquidation, dissolution, or winding up of the Company or any member of the group;

(ii)

authorize or issue any additional shares, other equity interests in the Company or any convertible securities into such equity interests;

(iii)

effect any public offering or listing of the equity securities of the Company; or

(iv)

purchase, redeem, pay or declare any dividend on any shares or other equity interests in the Company.

Dividends

All dividends shall be declared and paid pro rata according to the number of shares held by each member entitled to receive dividends. The Company’s board of directors may deduct from any dividend all sums of money presently payable by the member to the Company on account of calls.

Liquidation

In the event of a liquidation, dissolution or winding up of, or a return of capital by the Company, the ordinary shares will rank equally with the Series A preferred shares after the payment of the liquidation preference of $10 for Series A preferred shares.

Board of Directors

The board of directors shall consist of a maximum of seven directors, who shall be appointed by a majority of the Company’s issued and outstanding ordinary shares and a majority of the Company’s directors. The chairman of the Company will be a director appointed by a majority of the Company’s directors.

Series A Preferred Shares

The following represent the Series A preferred share transactions of the Company from its incorporation through December 31, 2015:

•

In February 2014, holders of $9,602 of related party notes payable agreed to convert such notes into 2,365,139 Series A preferred shares and 1,515,596 ordinary shares.

•

In connection with the private placement of Series B preferred shares on August 14, 2015, holders of the Company’s preference shares agreed to rename the existing “preference shares” as “Series A preferred shares.” In addition, as further described below, the terms of the Series A preferred shares were amended to remove their right of first refusal and to provide for their right to convert on a one-for-one basis into an aggregate of 3,901,348 ordinary shares at any time at the election of the holder. The rights of the Series A preferred shares are identical to the ordinary shares other than: (1) no voting rights other than in limited circumstances, (2) the right to a non-cumulative dividend if and when declared by our board of directors and (3) the right to convert the Series A preferred shares at any time on a one-for-one basis into ordinary shares at the discretion of the holder. The Company’s shareholders, including holders of Series A preferred shares, entered into an investors’ rights agreement and a voting agreement with the Company in connection with the private placement. Pursuant to the terms of the voting agreement, investors who hold at least 1,212,477 shares of registerable securities, including holders of Series A preferred shares and Series B preferred shares, have a right to purchase certain new securities offered by the Company. Additionally, in the event of the sale of 50% or more of the voting power of the company or a deemed liquidation event, if the holders of at least a majority of the ordinary shares and the holders of 56% of the Series B preferred shares vote to a sale of the Company, they have the right to force the other shareholders, including the holders of Series A preferred shares, to agree to such a sale.

•

In September 2015, the terms of the Series A preferred shares were further amended to provide that, upon the mandatory conversion of Series B preferred shares, which occurred on the completion of the initial public offering, the existing right of Series A preferred shares to a non-cumulative dividend if and when declared by our board of directors ceased and was replaced by a liquidation preference consisting of $0.0024743 per Series A preferred share, or an aggregate of $10 based on the number of Series A preferred shares outstanding at the date of the amendment.

The Company has accounted for the September 2015 amendment to the Series A preferred shares as a modification of the preferred shares based on upon a qualitative assessment of the amendment. The Company has not adjusted the carrying value of the Series A preferred shares since the fair value of the Series A preferred shares immediately prior and subsequent to the modification date resulted in an immaterial change in fair value.

The addition of the liquidation preference to the Series A preferred shares, however, resulted in the reclassification of the Series A preferred shares from permanent shareholders’ equity to temporary shareholders’ equity since the holders of the Series A preferred shares are entitled to a liquidation preference upon a deemed liquidation event, which is outside the control of the Company. In the event a deemed liquidation event were to occur, the Company would adjust the carrying value of the Series A preferred shares to their liquidation value, which amounts to $10 in the aggregate.

The Series A preferred shares have no par value and there is no authorized share capital under Singapore law. The Series A preferred shares are not redeemable.

Series B Preferred Shares Converted in Connection with Initial Public Offering

The following represents the historical Series B preferred share transactions of the Company from January 1, 2015 through the completion of our initial public offering:

•

On August 14, 2015, the Company issued an aggregate of 5,334,892 Series B preferred shares at a purchase price of $12.37 per share to certain third-party investors for $62,532 of net proceeds.

•

Upon the completion of the initial public offering on November 16, 2015, all of the outstanding Series B preferred shares of the Company automatically converted into 5,334,892 of the Company’s ordinary shares.

Prior to the conversion of the Series B preferred shares into ordinary shares, the Series B preferred shares had a liquidation preference over the Series A preferred shareholders and ordinary shareholders equal to the original per share amount paid of $12.37 per share, plus any declared plus unpaid dividends, if any. Additionally, the holders of Series B preferred shares were entitled to voting rights, however, the Series B preferred shareholders were not entitled to any preferential dividends and their shares were not redeemable.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 4.E)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

+ Details

Share-Based Compensation

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-Based Compensation

7. SHARE-BASED COMPENSATION

In December 2014, the Company’s board of directors adopted the WAVE Life Sciences Ltd. 2014 Equity Incentive Plan (the “2014 Plan”), and reserved 1,763,714 ordinary shares for issuance under this plan, which, as approved, was increased to 5,064,544 in 2015.

The 2014 Plan authorizes the board of directors or a committee of the board to grant incentive share options, non-qualified share options, or NQSOs, share appreciation rights and restricted awards to eligible employees, outside directors and consultants of the Company. Options generally vest over a period of three or four years, and options that lapse or are forfeited are available to be granted again. The contractual life of all options is ten years from the date the option begin to vest.

During the year ended December 31, 2015, the Company granted options to purchase 2,215,342 ordinary shares to employees, directors and non-employees. The Company did not grant any share options in 2014 and 2013. As of December 31, 2015, 2,658,346 ordinary shares remained available for future grant.

The Company recorded share-based compensation expense of $4,024 for the year ended December 31, 2015, of which $1,614 related to options granted to non-employees. The Company did not have any share-based compensation expense in 2014 and 2013. The Company measures and records the value of options granted to non-employees over the period of time services are provided and, as such, unvested portions are subject to re-measurement at subsequent reporting periods.

Share option activity under the 2014 Plan is summarized as follows:


	Number of Shares⁽¹⁾		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value⁽²⁾
Outstanding as of January 1, 2015		—
Granted		2,215,342	$	3.88

Outstanding as of December 31, 2015		2,215,342	$	3.88		9.30	$	26,740

Options exercisable as of December 31, 2015		700,779	$	2.48		9.20	$	9,443

Options vested and expected to vest as of December 31, 2015		2,139,612	$	3.86		9.30	$	25,875

⁽¹⁾	Includes 547,502 options granted to non-employees during March 2015.

⁽²⁾	The aggregate intrinsic value of options is calculated as the difference between the exercise price of the share options and the fair value of the Company’s ordinary shares for those share options that had exercise prices lower than the fair value of the ordinary shares as of the end of the period.

The assumptions used in the Black-Scholes option pricing model to determine the fair value of share options granted to employees during the period were as follows:


	Year ended December 31, 2015
Risk-free interest rate		1.56% - 1.89%
Expected term (in years)		5.52 - 6.12
Expected volatility		62.14% - 71.02%
Expected dividend yield		0%
Exercise price	$	2.47 - 13.08
Fair value of ordinary share	$	4.41 - 13.08

The assumptions used in the Black-Scholes option pricing model to determine the fair value of share options granted to non-employees during the period were as follows:


	Year Ended December 31, 2015
Risk-free interest rate		2.06% - 2.35%
Expected term (in years)		9.19 - 10.00
Expected volatility		62.65% - 69.80%
Expected dividend yield		0%
Exercise price	$	2.47
Fair value of ordinary share	$	4.41 - 15.95

Prior to the Company’s initial public offering in November 2015, the fair value of the Company’s ordinary shares was determined by the Company’s board of directors based upon a retrospective valuation with the assistance of a third-party valuation specialist and the guidance outlined in the American Institute of Certified Public Accountants Aid, Valuation of Privately-Held Company Equity Securities Issued as Compensation, also known as the Practice Aid, based on a variety of different objective and subjective factors, including the Company’s financial position, the status of development efforts within the Company, the composition and ability of the current scientific and management teams, the current climate in the marketplace, the illiquid nature of the Company’s shares, the prices of arm’s length sales of the Company’s ordinary shares, and the likelihood of achieving a liquidity event such as a public offering or sale of the Company. After the closing of the Company’s initial public offering, the board of directors determines the fair value of each underlying ordinary share based on the closing price of the Company’s ordinary shares as reported by the NASDAQ Global Market on the date of the grant.

As of December 31, 2015, the unrecognized compensation cost related to outstanding options was $4,942 for employees and $3,791 for non-employees and is expected to be recognized as expense over a weighted-average period of approximately 2.51 years. For the year ended December 31, 2015, the weighted-average grant date fair value per granted option was $6.64.

In March 2015, the Company granted 190,856 fully-vested ordinary shares to an executive of the Company and the Company recorded compensation expense in the amount of $842.

Share-based compensation expense for the year ended December 31, 2015 was classified in the consolidated statements of operations as follows:


	Year Ended December 31, 2015
Research and development expenses	$	2,268
General and administrative expenses		1,756

Total share-based compensation	$	4,024

Lease Arrangements

12 Months Ended

Dec. 31, 2015

Leases [Abstract]

Lease Arrangements

8. LEASE ARRANGEMENTS

The Company enters into leasing arrangements for its facilities as well as certain equipment. A summary of the arrangements are as follows:

Operating Leases

In April 2015, the Company entered into a lease agreement for an office and laboratory facility in Cambridge, Massachusetts, which commenced in October 2015 with a term of 7.5 years with a five year renewal option to extend the lease. In connection with the lease, the Company issued the lessor a letter of credit in the amount of $1,000, which is recorded as restricted cash on the consolidated balance sheets at December 31, 2015.

Previously, the Company leased its corporate office space in Boston, Massachusetts under a non-cancellable operating sublease with SNBL, a related party. On September 22, 2015, the Company terminated its sublease with SNBL and exited the premises on October 2, 2015. As a result of the termination of the sublease, the Company recorded approximately $201 of additional depreciation and $91 of exit costs during the year ended December 31, 2015. In connection with the termination, the Company agreed to guarantee SNBL certain obligations of an unrelated third party who entered into a sublease agreement with SNBL effective October 2, 2015. The guarantee provides that in the event the sub-lessee does not meet its lease obligations to SNBL, the Company will make the required payments. The guarantee agreement is effective through August 2019, when the final lease payments are due, and coincides with the original expiration of the lease. The Company simultaneously entered into an indemnification agreement with the sub-lessee to indemnify the Company for any costs incurred under the guaranty made by the Company to SNBL. The maximum amount of the guarantee over the three year and six month sub-lease period is $600, exclusive of any indemnification from the sub-lessee.

Future minimum lease payments under the Company’s non-cancelable operating leases as of December 31, 2015, are as follows:


	Amount
Year ending December 31:
2016		845
2017		1,030
2018		1,321
2019		1,360
Thereafter		4,711

	$	9,267

The Company recorded rent expense of $537, $294 and $248 for the years ended December 31, 2015, 2014 and 2013, respectively.

Capital Lease

In April 2015, the Company entered in a three year lease to acquire laboratory equipment, which has been accounted for as a capital lease. The capital asset was valued at $268 and is included in property and equipment, net, along with accumulated amortization of $27 as of December 31, 2015.

- Definition

The entire disclosure for lessor entity's leasing arrangements for operating, capital and leveraged leases.

+ References + Details

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. COMMITMENTS AND CONTINGENCIES Technology Licenses Max-Planck Innovation GmbH In June 2015, the Company entered into an agreement with Max-Planck-Innovation GmbH (“Max-Planck”) through which it obtained a co-exclusive royalty-bearing, worldwide license with the right to sublicense to certain patent rights within a patent portfolio. The Company intends to develop and commercialize diagnostic and therapeutic products based on the Company’s patent rights under this license. Max-Planck retains the right to use the intellectual property licensed under the agreement for non-commercial purposes. The Company’s license is one of two maximum allowable co-exclusive licenses for this technology. If either license holder terminates its respective co-exclusive portion of the license, Max-Planck is obligated to grant the other party an exclusive license with substantially the same terms and conditions previously applicable to the terminated co- exclusive licensee. The Company is permitted to sublicense its rights under the license. The license requires that the Company use commercially reasonable efforts to develop and commercialize products under the agreement, whether solely or through its affiliates and sub-licensees. In order to secure the license, the Company made an upfront payment of $50 to Max-Planck and will be required to pay annual license maintenance fees of $30 to Max-Planck in June of each year under the agreement. The Company will be required to make payments based upon regulatory milestones, including the initiation of clinical trials, and product approval milestones totaling up to $1,575 for each licensed product reaching such clinical stage. In addition to milestone payments, the Company will be required to pay royalties, calculated as a percentage of cumulative annual net sales of a licensed product. The Company recorded the $50 up-front payment as research and development expense in its consolidated statements of operations for the year ended December 31, 2015. The agreement may be terminated by either party subject to certain conditions. Research Collaborations University of Oxford In April 2015, the Company entered into a translational research collaboration agreement with The Chancellor, Masters, and Scholars of the University of Oxford (“Oxford”). The agreement with Oxford involves characterizing the Company’s proprietary isomers in order to improve the pharmacology of oligonucleotides for the treatment of Duchenne muscular dystrophy. Under the agreement, the Company agreed to pay Oxford up to $380 to conduct specified research services for the Company’s benefit during an initial 18-month term, which may be extended by the parties. The Company will own the results of the research conducted under the collaboration, including any potential intellectual property inventions. The agreement may be terminated by either party subject to certain conditions. In the year ended December 31, 2015, the Company incurred and paid $208 to Oxford pursuant to the agreement, which was recorded as research and development expense in its consolidated statements of operations. The remaining $173 is due in 2016. The Children’s Hospital of Philadelphia In April 2015, the Company entered into a master sponsored research agreement with The Children’s Hospital of Philadelphia (“CHOP”). The agreement with CHOP involves characterization of the Company’s proprietary isomers for the treatment of Huntington’s disease. Under the agreement, the Company agreed to pay CHOP up to $194 to conduct research activities, on a project-by-project basis, for the Company’s benefit during a term that ends on the later of the five- year anniversary of the agreement or the date that the last research project is completed. Subject to certain conditions, the Company has a first and exclusive option to negotiate for a revenue-bearing license, exclusive or non-exclusive at its election, under all of CHOP’s interest in and to the CHOP intellectual property and the joint intellectual property resulting from each research project performed under the agreement, provided that the Company pays all costs for the preparation, filing, prosecution and maintenance of patents or other intellectual property protection in the case of an exclusive license or its pro rata costs in the case of a non-exclusive license. The agreement may be terminated by either party subject to certain conditions. In the year ended December 31, 2015, the Company incurred and paid $145 to CHOP pursuant to the agreement, which was recorded as research and development expense in its consolidated statements of operations. The remaining $49 is due in 2016. University of Dundee In September 2015, the Company entered into a research collaboration agreement with the University of Dundee, or Dundee. The research collaboration with Dundee involves characterizing our proprietary isomers in order to improve the pharmacology of oligonucleotides for the treatment of EBS. Under the agreement, both parties are obligated to use reasonable endeavors to carry out the research project in accordance with the agreed upon research plan. Under the agreement, the Company has agreed to pay Dundee up to $0.3 million to conduct specified research services for our benefit during an initial two-year term, which may be extended by the parties. As of December 31, 2015, the Company has paid $38 to the University of Dundee pursuant to the agreement, which was recorded at research and development expense in its consolidated statement of operations. The Company will own the results of the research conducted under the collaboration, including any potential intellectual property inventions, and may, at their own expense, elect to register and maintain any protection for the intellectual property included in or arising or derived from the results of the research, including patent applications, without payment of any additional compensation to Dundee. The agreement does not affect the respective ownership rights of any background information, intellectual property, technology, design or know-how owned by the parties that are not results of the research conducted under the collaboration. Dundee retains the right to use the results of the research for purposes of Dundee’s own internal academic teaching and other scholarly uses undertaken solely for education and academic research. Either the Company or Dundee may terminate the research collaboration in the event of the other party’s breach of the agreement, if such breach is capable of cure, but remains uncured after 60 days of receiving written notice of such breach, or upon the occurrence of certain bankruptcy events. Unasserted Claims In the ordinary course of business, the Company may be subject to legal proceedings, claims and litigation as the Company operates in an industry susceptible to patent legal claims. The Company accounts for estimated losses with respect to legal proceedings and claims when such losses are probable and estimable. Legal costs associated with these matters are expensed when incurred. The Company is not currently a party to any legal proceedings.

Net Loss Per Ordinary Share

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Net Loss Per Ordinary Share

10. NET LOSS PER ORDINARY SHARE

Basic loss per share is computed by dividing net loss attributable to ordinary shareholders by the weighted-average number of ordinary shares used in computing net loss per share attributable to ordinary shareholders:


	Year Ended December 31,
	2015			2014			2013
Numerator:
Net loss attributable to ordinary shareholders	$	(19,200	)	$	(5,229	)	$	(3,318	)

Denominator:
Weighted-average ordinary shares used in computing net loss per share attributable to ordinary shareholders–basic and diluted		10,501,455			3,911,556			1,743,014

Net loss per share, basic and diluted	$	(1.83	)	$	(1.34	)	$	(1.90	)

The Company’s potentially dilutive shares, which include outstanding share options to purchase ordinary shares, are considered to be ordinary share equivalents and are only included in the calculation of diluted net loss per share when their effect is dilutive.

The following potential ordinary shares, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share attributable to ordinary shareholders for the periods indicated because including them would have had an anti-dilutive effect:


	Year Ended December 31,
	2015		2014		2013
Options to purchase ordinary shares		2,215,342		—		—
Series A preferred shares		3,901,348		3,901,348		1,536,209

		6,116,690		3,901,348		1,536,209

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income Taxes

11. INCOME TAXES

The components of loss before income taxes were as follows:


	Year Ended December 31,
	2015			2014			2013
Singapore	$	(16,534	)	$	(4,542	)	$	(2,973	)
Rest of world		(2,622	)		(603	)		(675	)

Loss before income taxes	$	(19,156	)	$	(5,145	)	$	(3,648	)

During the year ended December 31, 2015, the Company recorded a tax provision of $44 which is a result of changes in the United States valuation allowance during the period. During the year ended December 31, 2014, the Company recorded a provision for income taxes of $84 due to income taxed in the United States. During the year ended December 31, 2013, the Company recorded a benefit for income taxes of $330 which is a result of changes in the United States valuation allowance during the period.

During the years ended December 31, 2015, 2014 and 2013, the Company recorded no income tax benefits for the net operating losses incurred in Japan and Singapore, due to its uncertainty of realizing a benefit from those items.

The deferred components of the benefit (provision) for income taxes were as follows:


	Year Ended December 31,
	2015			2014			2013
Current tax benefit (provision):
Singapore taxes	$	—		$	—		$	—
Rest of world taxes		(8	)		—			—

Total current benefit (provision) income taxes	$	(8	)	$	—		$	—

Deferred tax benefit (provision):
Singapore taxes	$	—		$	—		$	—
Rest of world taxes		(36	)		(84	)		330

Total deferred benefit (provision) income taxes	$	(36	)	$	(84	)	$	330

Total benefit (provision) income taxes	$	(44	)	$	(84	)	$	330

A reconciliation of the Singapore statutory income tax rate to the Company’s effective income tax rate is as follows:


	Year Ended December 31,
	2015			2014			2013
Singapore statutory income tax rate		17.0	%		17.0	%		17.0	%
Research and development tax credits		2.3			2.2			4.1
Permanent differences		5.5			—			(1.4	)
Foreign exchange loss		—			2.0			0.8
Changes in reserves for uncertain tax positions		(1.2	)		(2.2	)		(2.1	)
Foreign rate differential		1.2			4.5			3.9
Tax rate change		0.2			—			—
Change in deferred tax asset valuation allowance		(25.2	)		(25.1	)		(13.3	)

Effective income tax rate		(0.2	)%		(1.6	)%		9.0	%

The components of the Company’s deferred tax assets as of December 31, 2015 and 2014 are as follows:


	December 31,
	2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	7,037		$	1,298
Research and development credits		460			384
Accrued expenses		58			63
Stock compensation		218			—
Deferred expenses		—			1,295
Other		149			94

		7,922			3,134
Valuation allowance		(7,466	)		(2,658	)

Total deferred tax assets		456			476
Depreciation		(246	)		(230	)

Total deferred tax liability		(246	)		(230	)

Net deferred tax asset (liability)	$	210		$	246

A roll-forward of the valuation allowance for the years ended December 31, 2015, 2014 and 2013 is as follows:


	Year Ended December 31,
	2015			2014			2013
Balance at beginning of year	$	2,658		$	1,534		$	1,209
Increase in valuation allowance		4,818			1,292			864
Reversal of valuation allowance		—			—			(379	)
Effect of foreign currency translation		(10	)		(168	)		(160	)

Balance at end of year	$	7,466		$	2,658		$	1,534

As of December 31, 2015 and 2014, the Company has net operating loss carryforwards in the United States of $1,837 and $2,115, respectively, available to offset future U.S. federal taxable income and approximately $1,871 and $2,365, respectively, available to reduce future state taxable income. The U.S. federal and state net operating losses begin to expire in 2030. As of December 31, 2015 and 2014, the Company also has United States research and development credit carryforwards of approximately $674 and $367, respectively, available to offset future U.S. federal income taxes and approximately $400 and $204, respectively, available to offset future state income taxes. The U.S. federal and state research and development credits will begin to expire in 2030 and 2025, respectively.

As of December 31, 2015 and 2014, the Company has net operating loss carryforwards in Japan of $4,316 and $3,535, respectively, which may be available to offset future income tax liabilities and begin to expire in 2015.

As of December 31, 2015 and 2014, the Company has net operating loss carryforwards in Singapore of $31,843 and $0, respectively, which may be available to offset future income tax liabilities and can be carried forward indefinitely.

The Company has evaluated the positive and negative evidence bearing upon its ability to realize its deferred tax assets. Management has considered the Company’s history of cumulative net losses incurred since inception and its lack of commercialization of any products or generation of any revenue from product sales since inception and has concluded that it is more likely than not that the Company will not realize the benefits of the deferred tax assets in Japan and Singapore. Accordingly, a full valuation allowance has been established against those deferred tax assets as of December 31, 2015 and 2014. The valuation allowance increased by approximately $4,818 in 2015, $1,292 in 2014 and $864 in 2013 primarily as a result of operating losses generated with no corresponding financial statement benefit. The Company may release this valuation allowance when management determines that it is more likely than not that the deferred tax assets will be realized. Any release of valuation allowance will be recorded as a tax benefit increasing net income.

At December 31, 2013, the Company determined that it was more likely than not that the Company would be able to realize the majority of the United States deferred tax assets primarily related to United States federal research and development credits, as a result of the research services agreement established between Singapore and the United States in 2013, which results in marginal profitability in the United States in 2013 and for the foreseeable future. Accordingly, the Company reversed $379 of its valuation allowance on United States federal and state deferred tax assets in 2013.

The Company’s reserves related to taxes and its accounting for uncertain tax positions are based on a determination of whether and how much of a tax benefit taken by the Company in its tax filings or positions is more-likely-than-not to be realized following resolution of any potential contingencies present related to the tax benefit.

A summary of activity in the Company’s unrecognized tax benefits is as follows:


	2015		2014		2013
Unrecognized tax benefit during the year	$	1,025	$	901	$	815
Tax positions related to the current year		255		124		86

Unrecognized tax benefit end of year	$	1,280	$	1,025	$	901

As of December 31, 2015, 2014 and 2013, the total amount of gross unrecognized tax benefits in the United States, which excludes interest and penalties, was $1,280, $1,025 and $901, respectively. At December 31, 2015, $997 million of the net unrecognized tax benefits, respectively, would affect the Company’s annual effective tax rate if recognized.

As discussed in Note 2, the Company early adopted ASU 2013-11 and therefore unrecognized tax benefits related to net operating losses are netted against the related deferred tax asset. The Company believes it is reasonably possible that approximately $700 of its unrecognized tax benefits may decrease by the end of 2016 as a result of the Company’s intention to amend its tax filings for transfer pricing in prior years. The impact of the reversal of the uncertain tax benefit will reduce the net operating loss carryforwards in the United States.

The Company’s policy is to record interest and penalties related to income taxes as part of its income tax provision. As of December 31, 2015 and 2014, the Company had no accrued interest or penalties related to uncertain tax positions, and no amounts have been recognized in the Company’s statements of operations and comprehensive loss.

The Company files income tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by various taxing authorities in the United States, Japan, and Singapore. There are currently no pending income tax examinations. Tax years from 2012 to the present are still open to examination in the United States, from 2008 to the present in Japan, and from 2012 to the present in Singapore. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service and state tax authorities to the extent utilized in a future period.

As of December 31, 2015 and 2014, $24 and $484, respectively, of cash was held by the subsidiaries outside of Singapore. The Company does not provide for Singapore income tax or foreign withholding taxes on foreign unrepatriated earnings, as the Company intends to permanently reinvest undistributed earnings in its foreign subsidiaries. If the Company decides to change this assertion in the future to repatriate any additional foreign earnings, the Company may be required to accrue and pay taxes. Because of the complexity of Singapore and foreign tax rules applicable to the distribution of earnings from foreign subsidiaries to Singapore, the determination of the unrecognized deferred tax liability on these earnings is not practicable.

Utilization of the net operating loss carryforwards and research and development tax credit carryforwards in the United States may be subject to a substantial annual limitation under Section 382 of the Internal Revenue Code of 1986 due to ownership changes that have occurred previously or that could occur in the future. These ownership changes may limit the amount of carryforwards that can be utilized annually to offset future taxable income. In general, an ownership change, as defined by Section 382, results from transactions increasing the ownership of certain shareholders or public groups in the shares of a corporation by more than 50% over a three-year period. The Company has completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes since its formation. The results of this study indicated that the Company experienced ownership changes as defined by Section 382 of the Code. The limitations will not have a material impact on the Company’s ability to utilize its research and development credit carryforwards to offset future tax liabilities.

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2015
Postemployment Benefits [Abstract]
Employee Benefit Plans	12. EMPLOYEE BENEFIT PLANS In 2013, the Company adopted a 401(k) retirement and savings plan (the “401(k) Plan”) covering all U.S.-based employees. The 401(k) Plan allows employees to make pre-tax contributions up to the maximum allowable amount set by the IRS. Under the 401(k) Plan, the Company may make discretionary contributions as approved by the board of directors. The Company did not make contributions to the 401(k) Plan during the years ended December 2015, 2014, and 2013. The Company has a J401(k) defined contribution pension plan covering all Japan-based permanent employees that was adopted in 2010. The J401(k) defined contribution pension plan allows the Company to make pre-tax contributions up to the maximum allowable amount set by the chief officer of the Kyushu Regional Bureau of Health and Welfare’s approval and company’s wage regulation. Under the J401(k) defined contribution pension plan, the Company may make discretionary contributions as approved by the Board of Directors. The Company has made contributions of $7 through December 31, 2015.

Related Parties

12 Months Ended

Dec. 31, 2015

Related Parties

13. RELATED PARTIES

The Company had the following related party transactions for the periods presented in the accompanying consolidated financial statements, which have not otherwise been discussed in these notes to the consolidated financial statements:

•

The Company had cash of $115 and $17 at December 31, 2015 and 2014, respectively, in depository accounts with one of its investors, who became an investor in February 2014.

•

The Company made payments for lease rentals in the amount of $178 and $214 to SNBL, a related party, for the years ended December 31, 2015 and 2014, respectively.

•

Pursuant to the terms of a service agreement previously held with SNBL, a related party, the Company paid SNBL $119, $71, and $245 in the years ended December 31, 2015, 2014 and 2013, respectively, for accounting and administrative services provided to the Company and its affiliates.

•

In 2012, the Company entered into a consulting agreement with a shareholder for services in the capacity as a scientific advisor. The consulting agreement does not have a certain term and may be terminated by either party upon 14 days’ prior written notice. The Company pays the shareholder $13 per month and reimbursement for certain expenses.

•

The Company also has an informal consulting arrangement with a shareholder in the amount of 250 Japanese yen, or $2, per month, plus reimbursement of certain expenses, for scientific advisory services.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References + Details

Geographic Data

12 Months Ended

Dec. 31, 2015

Text Block [Abstract]

Geographic Data

14. GEOGRAPHIC DATA

The Company’s long-lived assets consist of property and equipment and are located in the following geographical areas:


	Year ended December 31,
	2015		2014		2013
Asia	$	578	$	745	$	777
United States		2,211		524		607

Total long-lived assets	$	2,789	$	1,269	$	1,384

Selected Quarterly Financial Information (Unaudited)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Information (Unaudited)

15. SELECTED QUARTERLY FINANCIAL INFORMATION (UNAUDITED)

Selected quarterly results from operations for the years ended December 31, 2015 and 2014 are as follows:


	2015 Quarter Ended
	March 31			June 30			September 30			December 31
Revenues	$	26		$	126		$	—		$	—
Operating expenses		3,491			3,755			4,990			7,214
Net loss		(3,465	)		(3,700	)		(4,936	)		(7,099	)
Basic and diluted net loss per ordinary share	$	(0.42	)	$	(0.40	)	$	(0.54	)	$	(0.46	)


	2014 Quarter Ended
	March 31			June 30			September 30			December 31
Revenues	$	—		$	—		$	—		$	—
Operating expenses		968			1,292			1,354			1,780
Net loss		(400	)		(1,717	)		(1,363	)		(1,749	)
Basic and diluted net loss per ordinary share	$	(0.14	)	$	(0.40	)	$	(0.32	)	$	(0.41	)

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Share Splits

Share Splits

Principles of Consolidation

Principles of Consolidation

Use of Estimates

Use of Estimates

Segment Data

Segment Data

Foreign Currency Translation

Foreign Currency Translation

Fair Value of Financial Instruments

Fair Value of Financial Instruments

Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date of identical, unrestricted assets.

Concentration of Credit Risk

Concentration of Credit Risk

Restricted Cash

Restricted Cash

Property and Equipment

Property and Equipment


Furniture and Equipment		3-7 years
Leasehold Improvements		Shorter of life of lease or useful life

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets

Through December 31, 2015, the Company has not recognized any impairment charges.

Deferred Offering Costs

Deferred Offering Costs

Revenue Recognition

Revenue Recognition

Collaboration Agreement

Product Revenue

The Company has had no product revenue to date.

Allowance for Doubtful Accounts

Allowance for Doubtful Accounts

Research and Development Costs

Research and Development Costs

Government Grants

Government Grants

The Company recognized other income of $155, $160 and $43 for the years ended December 31, 2015, 2014 and 2013, respectively, which is included in the consolidated statements of operations.

Net Loss per Share

Net Loss per Share

License Agreements and Patent Costs

License Agreements and Patent Costs

Costs associated with licenses of technology and patent costs are expensed as incurred and are generally included in research and development expense in the consolidated statements of operations.

Share-Based Compensation

Share-Based Compensation

Income Taxes

Income Taxes

The Company recognizes interest and penalties related to uncertain tax positions in the income tax provision on the consolidated statements of operations.

Recently Adopted Accounting Pronouncements

Recently Adopted Accounting Pronouncements

Recently Issued Accounting Pronouncements

Recently Issued Accounting Pronouncements

Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Schedule of Estimated Useful Life of Assets

Depreciation is calculated on a straight-line basis over the following estimated useful lives of the assets:


Furniture and Equipment		3-7 years
Leasehold Improvements		Shorter of life of lease or useful life

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment, Net

Property and equipment, net, consists of the following


	December 31,
	2015			2014
Furniture and equipment	$	3,936		$	2,331
Fixed assets in progress		198			—
Leasehold improvements		267			147

Total		4,401			2,478
Less accumulated depreciation and amortization		(1,612	)		(1,209	)

Property and equipment, net	$	2,789		$	1,269

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2015

Payables and Accruals [Abstract]

Summary of Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consist of the following:


	December 31,
	2015		2014
Accrued compensation	$	—	$	315
Accrued audit fees		400		—
Accrued vacation		191		113
Other		354		177

Total accrued expenses and other current liabilities	$	945	$	605

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

Summary of Share Option Activity

Share option activity under the 2014 Plan is summarized as follows:


	Number of Shares⁽¹⁾		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value⁽²⁾
Outstanding as of January 1, 2015		—
Granted		2,215,342	$	3.88

Outstanding as of December 31, 2015		2,215,342	$	3.88		9.30	$	26,740

Options exercisable as of December 31, 2015		700,779	$	2.48		9.20	$	9,443

Options vested and expected to vest as of December 31, 2015		2,139,612	$	3.86		9.30	$	25,875

⁽¹⁾	Includes 547,502 options granted to non-employees during March 2015.

⁽²⁾	The aggregate intrinsic value of options is calculated as the difference between the exercise price of the share options and the fair value of the Company’s ordinary shares for those share options that had exercise prices lower than the fair value of the ordinary shares as of the end of the period.

Summary of Share-based Compensation Expense Classified in Consolidated Statements of Operations

Share-based compensation expense for the year ended December 31, 2015 was classified in the consolidated statements of operations as follows:


	Year Ended December 31, 2015
Research and development expenses	$	2,268
General and administrative expenses		1,756

Total share-based compensation	$	4,024

Employee Stock Option [Member]

Summary of Fair Value of Share Options Granted

The assumptions used in the Black-Scholes option pricing model to determine the fair value of share options granted to employees during the period were as follows:


	Year ended December 31, 2015
Risk-free interest rate		1.56% - 1.89%
Expected term (in years)		5.52 - 6.12
Expected volatility		62.14% - 71.02%
Expected dividend yield		0%
Exercise price	$	2.47 - 13.08
Fair value of ordinary share	$	4.41 - 13.08

Non-Employees Stock Option [Member]

Summary of Fair Value of Share Options Granted

The assumptions used in the Black-Scholes option pricing model to determine the fair value of share options granted to non-employees during the period were as follows:


	Year Ended December 31, 2015
Risk-free interest rate		2.06% - 2.35%
Expected term (in years)		9.19 - 10.00
Expected volatility		62.65% - 69.80%
Expected dividend yield		0%
Exercise price	$	2.47
Fair value of ordinary share	$	4.41 - 15.95

Lease Arrangements (Tables)

12 Months Ended

Dec. 31, 2015

Leases [Abstract]

Future Minimum Lease Payments Under Operating Leases

Future minimum lease payments under the Company’s non-cancelable operating leases as of December 31, 2015, are as follows:


	Amount
Year ending December 31:
2016		845
2017		1,030
2018		1,321
2019		1,360
Thereafter		4,711

	$	9,267

Net Loss Per Ordinary Share (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Summary of Basic and Diluted Net Loss Per Ordinary Share


	Year Ended December 31,
	2015			2014			2013
Numerator:
Net loss attributable to ordinary shareholders	$	(19,200	)	$	(5,229	)	$	(3,318	)

Denominator:
Weighted-average ordinary shares used in computing net loss per share attributable to ordinary shareholders–basic and diluted		10,501,455			3,911,556			1,743,014
Net loss per share, basic and diluted	$	(1.83	)	$	(1.34	)	$	(1.90	)

Anti-Dilutive Shares Excluded from Calculation of Diluted Net Loss Per Ordinary Share


	Year Ended December 31,
	2015		2014		2013
Options to purchase ordinary shares		2,215,342		—		—
Series A preferred shares		3,901,348		3,901,348		1,536,209

		6,116,690		3,901,348		1,536,209

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Components of Loss Before Income Taxes

The components of loss before income taxes were as follows:


	Year Ended December 31,
	2015			2014			2013
Singapore	$	(16,534	)	$	(4,542	)	$	(2,973	)
Rest of world		(2,622	)		(603	)		(675	)

Loss before income taxes	$	(19,156	)	$	(5,145	)	$	(3,648	)

Deferred Components of Benefit (Provision) for Income Taxes

The deferred components of the benefit (provision) for income taxes were as follows:


	Year Ended December 31,
	2015			2014			2013
Current tax benefit (provision):
Singapore taxes	$	—		$	—		$	—
Rest of world taxes		(8	)		—			—

Total current benefit (provision) income taxes	$	(8	)	$	—		$	—

Deferred tax benefit (provision):
Singapore taxes	$	—		$	—		$	—
Rest of world taxes		(36	)		(84	)		330

Total deferred benefit (provision) income taxes	$	(36	)	$	(84	)	$	330

Total benefit (provision) income taxes	$	(44	)	$	(84	)	$	330

Components of Deferred Tax Assets

The components of the Company’s deferred tax assets as of December 31, 2015 and 2014 are as follows:


	December 31,
	2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	7,037		$	1,298
Research and development credits		460			384
Accrued expenses		58			63
Stock compensation		218			—
Deferred expenses		—			1,295
Other		149			94

		7,922			3,134
Valuation allowance		(7,466	)		(2,658	)

Total deferred tax assets		456			476
Depreciation		(246	)		(230	)

Total deferred tax liability		(246	)		(230	)

Net deferred tax asset (liability)	$	210		$	246

Summary of Valuation Allowance

A roll-forward of the valuation allowance for the years ended December 31, 2015, 2014 and 2013 is as follows:


	Year Ended December 31,
	2015			2014			2013
Balance at beginning of year	$	2,658		$	1,534		$	1,209
Increase in valuation allowance		4,818			1,292			864
Reversal of valuation allowance		—			—			(379	)
Effect of foreign currency translation		(10	)		(168	)		(160	)

Balance at end of year	$	7,466		$	2,658		$	1,534

Summary of Activity in Unrecognized Tax Benefits

A summary of activity in the Company’s unrecognized tax benefits is as follows:


	2015		2014		2013
Unrecognized tax benefit during the year	$	1,025	$	901	$	815
Tax positions related to the current year		255		124		86

Unrecognized tax benefit end of year	$	1,280	$	1,025	$	901

Singapore [Member]

Reconciliation of Statutory Income Tax Rate

A reconciliation of the Singapore statutory income tax rate to the Company’s effective income tax rate is as follows:


	Year Ended December 31,
	2015			2014			2013
Singapore statutory income tax rate		17.0	%		17.0	%		17.0	%
Research and development tax credits		2.3			2.2			4.1
Permanent differences		5.5			—			(1.4	)
Foreign exchange loss		—			2.0			0.8
Changes in reserves for uncertain tax positions		(1.2	)		(2.2	)		(2.1	)
Foreign rate differential		1.2			4.5			3.9
Tax rate change		0.2			—			—
Change in deferred tax asset valuation allowance		(25.2	)		(25.1	)		(13.3	)

Effective income tax rate		(0.2	)%		(1.6	)%		9.0	%

Geographic Data (Tables)

12 Months Ended

Dec. 31, 2015

Text Block [Abstract]

Summary of Long-Lived Assets by Geographical Areas

The Company’s long-lived assets consist of property and equipment and are located in the following geographical areas:


	Year ended December 31,
	2015		2014		2013
Asia	$	578	$	745	$	777
United States		2,211		524		607

Total long-lived assets	$	2,789	$	1,269	$	1,384

Selected Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Schedule of Selected Quarterly Results from Operations

Selected quarterly results from operations for the years ended December 31, 2015 and 2014 are as follows:


	2015 Quarter Ended
	March 31			June 30			September 30			December 31
Revenues	$	26		$	126		$	—		$	—
Operating expenses		3,491			3,755			4,990			7,214
Net loss		(3,465	)		(3,700	)		(4,936	)		(7,099	)
Basic and diluted net loss per ordinary share	$	(0.42	)	$	(0.40	)	$	(0.54	)	$	(0.46	)


	2014 Quarter Ended
	March 31			June 30			September 30			December 31
Revenues	$	—		$	—		$	—		$	—
Operating expenses		968			1,292			1,354			1,780
Net loss		(400	)		(1,717	)		(1,363	)		(1,749	)
Basic and diluted net loss per ordinary share	$	(0.14	)	$	(0.40	)	$	(0.32	)	$	(0.41	)

The Company - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		12 Months Ended
	Dec. 04, 2015	Nov. 16, 2015	Dec. 31, 2015	Nov. 30, 2015	Dec. 31, 2015
Subsidiary, Sale of Stock [Line Items]
Proceeds from sale of common stock					$ 101,444
IPO [Member]
Subsidiary, Sale of Stock [Line Items]
Number of shares issued and sold		6,375,000		6,375,000
Shares issued, price per share		$ 16.00		$ 16.00
Convertible preferred stock converted into common stock		5,334,892
Sale of common stock, Date					Nov. 16, 2015
Underwriters Over-Allotment Option [Member]
Subsidiary, Sale of Stock [Line Items]
Number of shares issued and sold	618,126		618,126
Shares issued, price per share	$ 16.00		$ 16.00		$ 16.00
Proceeds from sale of common stock	$ 100,366		$ 100,366

Significant Accounting Policies - Additional Information (Detail)			12 Months Ended
	Nov. 01, 2015	Nov. 18, 2014	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Significant Accounting Policies [Line Items]
Stock split description			The Company's board of directors and shareholders approved a 50-for-1 share split of the Company's outstanding ordinary and Series A preferred shares effective November 18, 2014. Additionally, on November 1, 2015, the Company's board of directors and shareholders approved a 4.0415917-for-1 share split of the Company's issued and outstanding ordinary shares, Series A preferred shares and Series B preferred shares.
Restricted cash			$ 1,055,000	$ 0	$ 0
Impairment charges			0
Deferred offering costs			0	72,000
Upfront amount related to research and development services				152,000
Product revenue			0
Other income			155,000	160,000	43,000
Reimbursable capital expenditures			$ 3,000	248,000	66,000
Description of Income tax benefit, likelihood of realized upon ultimate settlement			The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement.
Minimum [Member]
Significant Accounting Policies [Line Items]
Income tax examination, likelihood of settlement, percentage			50.00%
Ordinary Shares and Series A Preferred Shares [Member]
Significant Accounting Policies [Line Items]
Stock split ratio		50
Ordinary Shares, Series A Preferred Shares and Series B Preferred Shares [Member]
Significant Accounting Policies [Line Items]
Stock split ratio	4.0415917
Collaboration Agreement [Member]
Significant Accounting Policies [Line Items]
Deferred revenue			$ 152,000	$ 0	$ 0

Significant Accounting Policies - Schedule of Estimated Useful Lives of Assets (Detail)	12 Months Ended
	Dec. 31, 2015
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	Shorter of life of lease or useful life
Minimum [Member] \| Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Maximum [Member] \| Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	7 years

Property and Equipment - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 4,401	$ 2,478
Less accumulated depreciation and amortization	(1,612)	(1,209)
Property and equipment, net	2,789	1,269	$ 1,384
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	3,936	2,331
Fixed Assets in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	198
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 267	$ 147

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 594	$ 281	$ 276

Accrued Expenses - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accrued compensation		$ 315
Accrued audit fees	$ 400
Accrued vacation	191	113
Other	354	177
Total accrued expenses and other current liabilities	$ 945	$ 605

Related Party Notes Payable - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Feb. 28, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015	Jan. 31, 2015
Related Party Transaction [Line Items]
Additional borrowing			$ 6,172,000
Repayment of loan			2,500,000
Issuance of ordinary shares		4,263,472			21,551,423
Debt conversion, Converted instrument, Shares issued	1,515,596
Notes payable, related parties	$ 9,602,000	$ 9,602,000
Unsecured Loans [Member]
Related Party Transaction [Line Items]
Additional borrowing			6,172,000
Repayment of loan			2,500,000
Series A Preferred Shares [Member]
Related Party Transaction [Line Items]
Debt conversion, Converted instrument, Shares issued	2,365,139
Ordinary Shares [Member]
Related Party Transaction [Line Items]
Debt conversion, Converted instrument, Shares issued	1,515,596
Third-Party Investor [Member]
Related Party Transaction [Line Items]
Issuance of ordinary shares	2,263,291					4,769,077
Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member]
Related Party Transaction [Line Items]
Unsecured loans			$ 9,602,000	$ 6,174,000
Gain or loss recognized on transaction due to related party	$ 0
Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member] \| Unsecured Loans [Member]
Related Party Transaction [Line Items]
Debt instrument interest rate, minimum			1.18%	1.33%
Debt instrument interest rate, maximum			1.35%	1.58%
Debt instrument maturity year			2014	2013
Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member] \| Series A Preferred Shares [Member]
Related Party Transaction [Line Items]
Debt conversion, Converted instrument, Shares issued	2,365,139
Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member] \| Ordinary Shares [Member]
Related Party Transaction [Line Items]
Debt conversion, Converted instrument, Shares issued	1,515,596

Share Capital - Ordinary Shares - Additional Information (Detail) $ / shares in Units, $ in Thousands			1 Months Ended						12 Months Ended
	Dec. 04, 2015 USD ($) $ / shares shares	Nov. 16, 2015 $ / shares shares	Dec. 31, 2015 USD ($) Vote / shares $ / shares shares	Nov. 30, 2015 $ / shares shares	Mar. 31, 2015 shares	Jan. 31, 2015 USD ($) $ / shares shares	Feb. 28, 2014 USD ($) $ / shares shares	Oct. 31, 2013 shares	Dec. 31, 2015 USD ($) Director Vote / shares $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 shares	Sep. 28, 2015 USD ($)	Sep. 30, 2012 shares
Class of Stock [Line Items]
Shares issued			21,551,423						21,551,423	4,263,472
Notes payable, related parties \| $							$ 9,602			$ 9,602
Debt conversion, Converted instrument, Shares issued							1,515,596
Proceeds from sale of common stock \| $									$ 101,444
Common stock, par value \| $ / shares
Ordinary share holder, voting right									One vote for each ordinary share
Minimum percentage of issued and outstanding ordinary shares required for approval									75.00%
Voting rights, votes per share \| Vote / shares			1						1
Preferred stock, aggregate liquidation preference \| $			$ 10						$ 10			$ 10
Maximum number of directors on board \| Director									7
Singapore [Member]
Class of Stock [Line Items]
Common stock, par value \| $ / shares
Common stock, authorized			0						0
IPO [Member]
Class of Stock [Line Items]
Number of shares issued and sold		6,375,000		6,375,000
Shares issued, price per share \| $ / shares		$ 16.00		$ 16.00
Underwriters Over-Allotment Option [Member]
Class of Stock [Line Items]
Number of shares issued and sold	618,126		618,126
Shares issued, price per share \| $ / shares	$ 16.00		$ 16.00						$ 16.00
Proceeds from sale of common stock \| $	$ 100,366		$ 100,366
Ordinary Shares [Member]
Class of Stock [Line Items]
Conversion of ordinary shares to Series A preferred shares											(1,536,209)
Debt conversion, Converted instrument, Shares issued							1,515,596
Executive Officer [Member]
Class of Stock [Line Items]
Options to purchase common stock granted					190,856
Third-Party Investor [Member]
Class of Stock [Line Items]
Shares issued						4,769,077	2,263,291
Shares issued, Per Share \| $ / shares						$ 2.47	$ 2.47
Proceeds from issuance of shares \| $						$ 11,631	$ 5,585
Wave USA and Wave Japan [Member]
Class of Stock [Line Items]
Shares issued													2,020,794
Series A Preferred Shares [Member]
Class of Stock [Line Items]
Conversion of ordinary shares to Series A preferred shares								1,536,209			1,536,209
Debt conversion, Converted instrument, Shares issued							2,365,139

Share Capital - Series A Preferred Shares - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Aug. 14, 2014	Feb. 28, 2014	Dec. 31, 2014	Dec. 31, 2015	Sep. 30, 2015	Sep. 28, 2015
Class of Stock [Line Items]
Notes payable, related parties		$ 9,602	$ 9,602
Notes payable convert to shares		1,515,596
Minimum number of shares to be held to receive right to purchase new securities	1,212,477
Percentage of voting Right	50.00%
Preferred stock, aggregate liquidation preference				$ 10		$ 10
Preferred stock, par value
Series A Preferred Shares [Member]
Class of Stock [Line Items]
Notes payable convert to shares		2,365,139
Share issued for conversion	3,901,348
Preferred stock liquidation preference, per share					$ 0.0024743
Aggregate preferred stock liquidation preference, per share					$ 10
Series A Preferred Shares [Member] \| Singapore [Member]
Class of Stock [Line Items]
Preferred stock, par value
Preferred stock, shares authorized				0
Series B Preferred Shares [Member]
Class of Stock [Line Items]
Preferred stock, voting rights	56.00%
Preferred stock liquidation preference, per share				$ 12.37

Share Capital - Series B Preferred Shares - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Aug. 14, 2015	Dec. 31, 2015	Nov. 16, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Preferred stock, shares issued				3,901,348
Proceeds from issuance of preferred shares		$ 62,532
IPO [Member]
Class of Stock [Line Items]
Convertible preferred stock converted into common stock			5,334,892
Sale of common stock, Date		Nov. 16, 2015
Series B Preferred Shares [Member]
Class of Stock [Line Items]
Preferred stock, shares issued	5,334,892
Preferred shares issued, Per Share	$ 12.37
Proceeds from issuance of preferred shares	$ 62,532
Preferred stock liquidation preference, per share		$ 12.37

Share-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 4,024,000
Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock granted	190,856
2014 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares reserved for issuance			1,763,714
Number of shares authorized (in shares)		5,064,544
Contractual life of options		10 years
Options to purchase common stock granted		2,215,342	0	0
Ordinary shares available for future grant		2,658,346
Share-based compensation expense	$ 842,000	$ 4,024,000	$ 0	$ 0
Unrecognized stock-based compensation weighted average recognition period		2 years 6 months 4 days
Weighted average grant date fair value per granted option		$ 6.64
2014 Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense		$ 4,942,000
2014 Plan [Member] \| Non-Employees Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock granted	547,502
Share-based compensation expense		1,614,000
Unrecognized stock-based compensation expense		$ 3,791,000
2014 Plan [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock granted	190,856
2014 Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vesting period		3 years
2014 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vesting period		4 years

Share-Based Compensation - Summary of Share Option Activity (Detail) - 2014 Plan [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of Shares	2,215,342	0	0
Outstanding, Number of Shares, Ending Balance	2,215,342
Options exercisable, Number of Shares	700,779
Options vested and expected to vest, Number of Shares	2,139,612
Granted, Weighted Average Exercise Price	$ 3.88
Outstanding, Weighted Average Exercise Price, Ending Balance	3.88
Options exercisable, Weighted Average Exercise Price	2.48
Options vested and expected to vest, Weighted Average Exercise Price	$ 3.86
Outstanding, Weighted Average Remaining Contractual Term	9 years 3 months 18 days
Options exercisable, Weighted Average Remaining Contractual Term	9 years 2 months 12 days
Options vested and expected to vest, Weighted Average Remaining Contractual Term	9 years 3 months 18 days
Outstanding, Aggregate Intrinsic Value, Ending Balance	$ 26,740
Options exercisable, Aggregate Intrinsic Value	9,443
Options vested and expected to vest, Aggregate Intrinsic Value	$ 25,875

Share-Based Compensation - Summary of Share Option Activity (Parenthetical) (Detail) - 2014 Plan [Member] - shares	1 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock granted		2,215,342	0	0
Non-Employees Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock granted	547,502

Share-Based Compensation - Summary of Fair Value of Share Options Granted to Employees (Detail) - Employee Stock Option [Member]	12 Months Ended
	Dec. 31, 2015 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.56%
Risk-free interest rate, maximum	1.89%
Expected volatility, minimum	62.14%
Expected volatility, maximum	71.02%
Expected dividend yield	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 6 months 7 days
Exercise price	$ 2.47
Fair value of ordinary share	$ 4.41
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 1 month 13 days
Exercise price	$ 13.08
Fair value of ordinary share	$ 13.08

Share-Based Compensation - Summary of Fair Value of Share Options Granted to Non-Employees (Detail) - Non-Employees Stock Option [Member]	12 Months Ended
	Dec. 31, 2015 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	2.06%
Risk-free interest rate, maximum	2.35%
Expected volatility, minimum	62.65%
Expected volatility, maximum	69.80%
Expected dividend yield	0.00%
Exercise price	$ 2.47
Fair value of ordinary share, minimum	4.41
Fair value of ordinary share, maximum	$ 15.95
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	9 years 2 months 9 days
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	10 years

Share-Based Compensation - Summary of Share-based Compensation Expense Classified in Consolidated Statements of Operations (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	$ 4,024
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	2,268
General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	$ 1,756

Lease Arrangements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Leases [Line Items]
Issuance of letter of credit recorded as restricted cash	$ 1,055,000	$ 0	$ 0
Lease rent expense	$ 537,000	294,000	$ 248,000
Laboratory Equipment [Member]
Leases [Line Items]
Capital lease agreement period	3 years
Capital assets purchased	$ 268,000
Capital leases accumulated amortization	27,000
Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member]
Leases [Line Items]
Lease rent expense	$ 178,000	$ 214,000
2015 Cambridge, MA Lease [Member]
Leases [Line Items]
Lease agreement term	7 years 6 months
Lease extension period	5 years
2015 Cambridge, MA Lease [Member] \| Letter of Credit [Member]
Leases [Line Items]
Issuance of letter of credit recorded as restricted cash	$ 1,000,000
2015 Boston, MA Lease Termination [Member]
Leases [Line Items]
Guarantee agreement termination date	Aug. 31, 2019
2015 Boston, MA Lease Termination [Member] \| Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member]
Leases [Line Items]
Lease agreement term	3 years 6 months
Accelerated depreciation	$ 201,000
Additional exit costs related to termination of sublease agreement	91,000
Maximum amount of guarantee for sublease	$ 600,000

Lease Arrangements - Future Minimum Lease Payments Under Operating Leases (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2016	$ 845
2017	1,030
2018	1,321
2019	1,360
Thereafter	4,711
Total	$ 9,267

Commitments And Contingencies - Additional Information (Detail)	1 Months Ended			12 Months Ended
	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Apr. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) Licenses	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Commitments And Contingencies [Line Items]
Research and development				$ 9,057,000	$ 2,395,000	$ 1,920,000
Written notice for breach of contract				60 days
Max-Planck Innovation GmbH [Member]
Commitments And Contingencies [Line Items]
Number of licenses for technology \| Licenses				1
Upfront payment		$ 50,000
Annual license maintenance fee payable		30,000
Total regulatory milestone payments		$ 1,575,000
Research and development				$ 50,000
Max-Planck Innovation GmbH [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Number of maximum allowable co-exclusive licenses \| Licenses				2
University of Oxford [Member]
Commitments And Contingencies [Line Items]
Research and development				$ 208,000
Research and development plan expected term			18 months
Research and development due in 2016				173,000
University of Oxford [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Research and development			$ 380,000
The Children's Hospital of Philadelphia [Member]
Commitments And Contingencies [Line Items]
Research and development				145,000
Research and development due in 2016				49,000
The Children's Hospital of Philadelphia [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Research and development			$ 194,000
University Of Dundee [Member]
Commitments And Contingencies [Line Items]
Research and development				$ 38,000
Research and development plan expected term	2 years
University Of Dundee [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Research and development	$ 300,000

Net Loss Per Ordinary Share - Summary of Basic and Diluted Net Loss Per Ordinary Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator:
Net loss attributable to ordinary shareholders									$ (19,200)	$ (5,229)	$ (3,318)
Denominator:
Weighted-average ordinary shares used in computing net loss per share attributable to ordinary shareholders-basic and diluted									10,501,455	3,911,556	1,743,014
Net loss per share, basic and diluted	$ (0.46)	$ (0.54)	$ (0.40)	$ (0.42)	$ (0.41)	$ (0.32)	$ (0.40)	$ (0.14)	$ (1.83)	$ (1.34)	$ (1.90)

Net Loss Per Ordinary Share - Anti-Dilutive Shares Excluded from Calculation of Diluted Net Loss Per Ordinary Share (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Series A Preferred Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	3,901,348	3,901,348	1,536,209
Series B Preferred Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	6,116,690	3,901,348	1,536,209
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	2,215,342

Income Taxes - Components of Loss Before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Loss before income taxes	$ (19,156)	$ (5,145)	$ (3,648)
Singapore [Member]
Income Taxes [Line Items]
Loss before income taxes	(16,534)	(4,542)	(2,973)
Rest Of World [Member]
Income Taxes [Line Items]
Loss before income taxes	$ (2,622)	$ (603)	$ (675)

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Income tax provision	$ 44,000	$ 84,000	$ (330,000)
Available future U.S. federal taxable income offset	1,871,000
Available future state taxable income reduce	2,365,000
Net operating loss carryovers	7,037,000	1,298,000
Increase in valuation allowance	4,818,000	1,292,000	864,000
Reversal of valuation allowance			379,000
Gross unrecognized tax benefit	1,280,000	1,025,000	901,000	$ 815,000
Unrecognized tax benefit that could affect annual effective tax rate if recognized	997,000,000
Accrued interest and penalties related to uncertain tax positions	0	0
Interest and penalties recognized in statement of operations	0	0
Federal [Member]
Income Taxes [Line Items]
Research and development tax credit carryforward	$ 674,000	367,000
Tax credit carryforward expiration year	2030
State [Member]
Income Taxes [Line Items]
Research and development tax credit carryforward	$ 400,000	$ 204,000
Tax credit carryforward expiration year		2025
Subsidiaries Outside of Singapore [Member]
Income Taxes [Line Items]
Cash held by subsidiaries	24,000	$ 484,000
Adjustments for New Accounting Principle, Early Adoption [Member]
Income Taxes [Line Items]
Gross unrecognized tax benefit	700,000
United States [Member]
Income Taxes [Line Items]
Income tax provision	(44,000)	(84,000)	330,000
Operating loss carryforwards, net	$ 1,837,000	2,115,000
Tax years open to examination	2012
Japan [Member]
Income Taxes [Line Items]
Income tax provision	$ 0	0	0
Net operating loss carryovers	$ 4,316,000	3,535,000
Tax years open to examination	2008
Singapore [Member]
Income Taxes [Line Items]
Income tax provision	$ 0	0	$ 0
Net operating loss carryovers	$ 31,843,000	$ 0
Tax years open to examination	2012

Income Taxes - Deferred Components of Benefit (Provision) for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current tax benefit (provision):
Rest of world taxes	$ (8)
Deferred tax benefit (provision):
Total deferred benefit (provision) income taxes	(36)	$ (84)	$ 330
Total benefit (provision) income taxes	(44)	(84)	330
Rest Of World [Member]
Current tax benefit (provision):
Rest of world taxes	(8)
Deferred tax benefit (provision):
Total deferred benefit (provision) income taxes	$ (36)	$ (84)	$ 330

Income Taxes - Reconciliation of Statutory Income Tax Rate (Detail) - Singapore [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Singapore statutory income tax rate	17.00%	17.00%	17.00%
Research and development tax credits	2.30%	2.20%	4.10%
Permanent differences	5.50%		(1.40%)
Foreign exchange loss		2.00%	0.80%
Changes in reserves for uncertain tax positions	(1.20%)	(2.20%)	(2.10%)
Foreign rate differential	1.20%	4.50%	3.90%
Tax rate change	0.20%
Change in deferred tax asset valuation allowance	(25.20%)	(25.10%)	(13.30%)
Effective income tax rate	(0.20%)	(1.60%)	9.00%

Income Taxes - Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Net operating loss carryforwards	$ 7,037	$ 1,298
Research and development credits	460	384
Accrued expenses	58	63
Stock compensation	218
Deferred expenses		1,295
Other	149	94
Deferred tax assets, gross	7,922	3,134
Valuation allowance	(7,466)	(2,658)	$ (1,534)	$ (1,209)
Total deferred tax assets	456	476
Depreciation	(246)	(230)
Total deferred tax liability	(246)	(230)
Net deferred tax asset (liability)	$ 210	$ 246

Income Taxes - Summary of Valuation Allowance (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred Tax Assets, Net of Valuation Allowance [Abstract]
Balance at beginning of year	$ 2,658	$ 1,534	$ 1,209
Increase in valuation allowance	4,818	1,292	864
Reversal of valuation allowance			(379)
Effect of foreign currency translation	(10)	(168)	(160)
Balance at end of year	$ 7,466	$ 2,658	$ 1,534

Income Taxes - Summary of Activity in Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit during the year	$ 1,025	$ 901	$ 815
Tax positions related to the current year	255	124	86
Unrecognized tax benefit end of year	$ 1,280	$ 1,025	$ 901

Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
401(k) Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Discretionary contributions to defined contribution pension plan	$ 0	$ 0	$ 0
J401(k) [Member]
Defined Contribution Plan Disclosure [Line Items]
Discretionary contributions to defined contribution pension plan	$ 7

Related Parties - Additional Information (Detail) ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2015 JPY (¥)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Related Party Transaction [Line Items]
Lease rentals paid	$ 537		$ 294	$ 248
Third-Party Investor [Member]
Related Party Transaction [Line Items]
Related party transaction amount	115		17
Shin Nippon Biomedical Laboratories Ltd. (SNBL) [Member]
Related Party Transaction [Line Items]
Lease rentals paid	178		214
Payment for accounting and administrative services	$ 119		$ 71	$ 245
Scientific Advisor [Member] \| Consulting Agreement [Member]
Related Party Transaction [Line Items]
Consulting agreement termination notice period	14 days	14 days
Consulting service expenses	$ 13
Scientific Advisor [Member] \| Informal Consulting Arrangement [Member]
Related Party Transaction [Line Items]
Consulting service expenses	$ 2	¥ 250

Geographic Data - Summary of Long-Lived Assets by Geographical Areas (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Geographic Area Information [Line Items]
Property and equipment, net	$ 2,789	$ 1,269	$ 1,384
Asia [Member]
Geographic Area Information [Line Items]
Property and equipment, net	578	745	777
United States [Member]
Geographic Area Information [Line Items]
Property and equipment, net	$ 2,211	$ 524	$ 607

Selected Quarterly Financial Information (Unaudited) - Summary of Selected Quarterly Results from Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Information [Abstract]
Revenues			$ 126	$ 26					$ 152
Operating expenses	$ 7,214	$ 4,990	3,755	3,491	$ 1,780	$ 1,354	$ 1,292	$ 968	19,450	$ 5,394	$ 3,574
Net loss	$ (7,099)	$ (4,936)	$ (3,700)	$ (3,465)	$ (1,749)	$ (1,363)	$ (1,717)	$ (400)	$ (19,200)	$ (5,229)	$ (3,318)
Basic and diluted net loss per ordinary share	$ (0.46)	$ (0.54)	$ (0.40)	$ (0.42)	$ (0.41)	$ (0.32)	$ (0.40)	$ (0.14)	$ (1.83)	$ (1.34)	$ (1.90)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details