UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

Information To Be Included in Statements Filed Pursuant to § 240.13d-1(a) and

Amendments Thereto Filed Pursuant to § 240.13d-2(a)

(Amendment No. 4)*

WAVE Life Sciences Ltd.

(Name of Issuer)

Ordinary Shares

(Title of Class of Securities)

Y95308105

(CUSIP Number)

Ken Takanashi

St. Luke’s Tower 12F, 8-1, Akashi-cho, Chuo-ku,

Tokyo 104-0044, Japan

+81-3-5565-6148

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

With Copies To:

Morgan, Lewis & Bockius LLP

ATTN: Bradley K. Edmister

101 Park Avenue, New York, New York 10178-0060

Telephone: +1-212-309-6110

January 24, 2019

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because off §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

This Amendment No. 4 amends the Schedule 13D filed with the Securities and Exchange Commission on November 25, 2015, as previously amended from time to time (the “Schedule 13D”). Unless otherwise stated herein, the Schedule 13D remains in full force and effect. Terms used herein and not otherwise defined herein shall have the meaning ascribed thereto in the Schedule 13D.

Item 5. Interest in Securities of the Issuer

Item 5 is hereby amended and restated in its entirety as follows:

The information in this Item 5(a) and in Row 13 of each cover page to this Schedule 13D with respect to SNBL, Mr. Takanashi and SNBL USA is based on an aggregate of 33,376,176 shares of the Issuer’s Ordinary Shares issued and outstanding as of January 24, 2019, as reported in the Issuer’s prospectus supplement, filed with the SEC on January 24, 2019.

(a) SNBL may be deemed to beneficially own 5,885,478 of the Issuer’s Ordinary Shares, representing 17.6% of the Issuer’s issued and outstanding shares and consisting of (i) 1,697,467 Ordinary Shares held by SNBL; (ii) 286,663 Ordinary Shares held by SNBL USA; (iii) 1,801,348 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL; and (iv) 2,100,000 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL USA.

Mr. Takanashi may be deemed to beneficially own 5,894,478 of the Issuer’s Ordinary Shares, representing 17.7% of the Issuer’s issued and outstanding shares and consisting of (i) 1,697,467 Ordinary Shares held by SNBL; (ii) 286,663 Ordinary Shares held by SNBL USA; (iii) 1,801,348 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL; (iv) 2,100,000 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL USA; and (v) 9,000 Ordinary Shares underlying options currently exercisable held by Mr. Takanashi.

SNBL USA may be deemed to beneficially own 2,386,663 of the Issuer’s Ordinary Shares, representing 7.2% of the Issuer’s issued and outstanding shares and consisting of 286,663 Ordinary Shares held by SNBL USA and 2,100,000 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL USA.

Each of the Reporting Persons expressly disclaims beneficial ownership of the securities of the Issuer owned by all other Reporting Persons except to the extent of its or his pecuniary interest therein.

(b) SNBL and Mr. Takanashi share the power to vote or dispose of the: (i) 1,697,467 Ordinary Shares held by SNBL; (ii) 286,663 Ordinary Shares held by SNBL USA; (iii) 1,801,348 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL; and (iv) 2,100,000 Ordinary Shares underlying immediately convertible Series A preferred shares held by SNBL USA.

SNBL USA shares the power to vote or dispose of the 286,663 Ordinary Shares it holds and the 2,100,000 Ordinary Shares underlying immediately convertible Series A preferred shares it holds.

(c) Not applicable.

(d) No other person is known to have the right to receive, or the power to direct the receipt of dividends from, any proceeds from the sale of the Ordinary Shares of the Issuer beneficially owned by any of the Reporting Persons.

(e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

Item 6 is hereby amended and supplemented by adding the following:

Third Amendment to December 28 Pledge Agreement

Pursuant to the Third Amendment to Pledge Agreement, dated as of June 27, 2018 (the “Third Amendment to December 28 Pledge Agreement”), to the December 28 Stock Pledge Agreement, Amendment to December 28 Pledge Agreement and Second Amendment to December 28 Pledge Agreement, dated as of December 28, 2016, June 30, 2017 and December 27, 2017, respectively, between SNBL USA and Kagoshima Bank, the secured obligations under the December 28 Stock Pledge Agreement, the Amendment to December 28 Pledge Agreement and the Second Amendment December 28 Pledge Agreement were amended to include a new loan from Kagoshima Bank to SNBL in the principal amount of ¥600,000,000 made pursuant to a loan agreement, dated as of June 27, 2018, between SNBL and Kagoshima Bank.

The foregoing description of the Third Amendment to December 28 Pledge Agreement is qualified in its entirety by reference to the full text of the Third Amendment to December 28 Pledge Agreement, which is filed herewith as Exhibit 99.14.

2018 Syndication Deed of Charge of Shares

SNBL, Kagoshima Bank and the Lenders (as defined in the 2018 Deed of Charge of Shares, dated September 14, 2018 (the “2018 Syndication Deed of Charge of Shares”), which is filed herewith as Exhibit 99.15), entered into the 2018 Syndication Deed of Charge of Shares whereby SNBL has pledged 938,846 Ordinary Shares for the benefit of the Lenders in order to secure the obligations of SNBL under a loan agreement, dated September 14, 2018, between SNBL and the Lenders.

The foregoing description of the 2018 Syndication Deed of Charge of Shares is qualified in its entirety by reference to the full text of the 2018 Syndication Deed of Charge of Shares, which is filed herewith as Exhibit 99.15.

Fourth Amendment to December 28 Pledge Agreement

Pursuant to the Fourth Amendment to Pledge Agreement, dated as of December 27, 2018 (the “Fourth Amendment to December 28 Pledge Agreement”), to the December 28 Stock Pledge Agreement, Amendment to December 28 Pledge Agreement, Second Amendment to December 28 Pledge Agreement and Third Amendment to December 28 Pledge Agreement, dated as of December 28, 2016, June 30, 2017, December 27, 2017 and June 27, 2018, respectively, between SNBL USA and Kagoshima Bank, the secured obligations under the December 28 Stock Pledge Agreement, the Amendment to December 28 Pledge Agreement, the Second Amendment to December 28 Pledge Agreement and the Third Amendment to December 28 Pledge Agreement were amended to include a new loan from Kagoshima Bank to SNBL in the principal amount of ¥600,000,000 made pursuant to a loan agreement, dated as of December 27, 2018, between SNBL and Kagoshima Bank.

The foregoing description of the Fourth Amendment to December 28 Pledge Agreement is qualified in its entirety by reference to the full text of the Fourth Amendment to December 28 Pledge Agreement, which is filed herewith as Exhibit 99.16.

Discharge and Release of Kagoshima Bank Deed of Charge of Shares

Pursuant to the Deed of Discharge and Release of Kagoshima Bank Deed of Charge of Shares, dated September 14, 2018, between SNBL and Kagoshima Bank, Kagoshima Bank discharged and released its security interest over 915,464 Ordinary Shares that were pledged by SNBL for the benefit of Kagoshima Bank, pursuant to the Kagoshima Bank Deed of Charge of Shares, dated September 15, 2017.

Discharge and Release of Syndication Deed of Charge of Shares

Pursuant to the Deed of Discharge and Release of Syndication Deed of Charge of Shares, dated September 14, 2018, between SNBL, Kagoshima Bank and the Lenders (as defined in the Syndication Deed of Charge of Shares), the Lenders discharged and released its security interest over 720,063 Ordinary Shares that were pledged by SNBL for the benefit of the Lenders, pursuant to the Syndication Deed of Charge of Shares, dated September 15, 2017.

Item 7. Materials to Be Filed as Exhibits

Item 7 is hereby amended and supplemented by adding the following:

Exhibit 99.14: Third Amendment to December 28 Pledge Agreement, dated June 27, 2018, by and between SNBL USA and Kagoshima Bank.

Exhibit 99.15: 2018 Syndication Deed of Charge of Shares, dated September 14, 2018, by and between SNBL, Kagoshima Bank and the Lenders.

Exhibit 99.16: Fourth Amendment to December 28 Pledge Agreement, dated December 27, 2018, by and between SNBL USA and Kagoshima Bank.

[The remainder of this page intentionally left blank]

SIGNATURE

After reasonable inquiry and to the best of the knowledge and belief, the undersigned certify that the information set forth in this Amendment No. 4 is true, complete and correct.

February 14, 2019

SCHEDULE 1

The following table sets forth the name and present principal occupation or employment, for each executive officer and director of Shin Nippon Biomedical Laboratories, Ltd. Each of the executive officers and directors of Shin Nippon Biomedical Laboratories, Ltd. listed below is a citizen of Japan.

Shin Nippon Biomedical Laboratories, Ltd.

SCHEDULE 2

The following table sets forth the name and present principal occupation or employment, for each executive officer and director of SNBL USA, Ltd. Each of the executive officers and directors of SNBL USA, Ltd. listed below is a citizen of Japan, except for Steven Meyer, a citizen of the United States.

SNBL USA, Ltd.

Exhibit 99.14

THIRD AMENDMENT TO PLEDGE AGREEMENT

THIS THIRD AMENDMENT TO PLEDGE AGREEMENT is dated as of June 27, 2018 (this “Amendment”) and is made by and between SNBL U.S.A. Ltd., a Washington corporation (“SNBL USA”) and The Kagoshima Bank, Ltd. (“Lender”).

WHEREAS, on December 28, 2016, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Prior Loan”), evidenced by that certain Loan Agreement dated as of December 28, 2016 made by Borrower and payable to the order of Lender (the “Original Loan Agreement”);

WHEREAS, on June 30, 2017, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Second Prior Loan”), evidenced by that certain Loan Agreement dated as of June 30, 2017 made by Borrower and payable to the order of Lender (the “Second Prior Loan Agreement” and collectively and severally with the Original Loan Agreement, the “Prior Loan Agreements”);

WHEREAS, on December 27, 2017, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Existing Loan”), evidenced by that certain Loan Agreement dated as of December 27, 2017 made by Borrower and payable to the order of Lender (the “Existing Loan Agreement”);

WHEREAS, Lender and SNBL USA are party to a Stock Pledge Agreement dated December 28, 2016, pursuant to which SNBL USA pledged all of its shares of stock issued by WaVe Life Sciences Pte. Ltd., a Singapore company, and certain other collateral to Lender to secure the Prior Loan, as amended by that certain Amendment to Pledge Agreement dated June 30, 2017, and Second Amendment to Pledge Agreement dated December 27, 2017, by and between SNBL USA and Lender (as so amended, the “Pledge Agreement”);

WHEREAS, it is contemplated that on or about the date hereof, the Existing Loan will be repaid in full and Lender intends to make a new loan to Borrower in the principal amount of Six Hundred Million Japanese Yen (¥600,000,000) (the “New Loan” and collectively with the Prior Loan, the Second Prior Loan and the Existing Loan, the “Loans”) and the parties hereto intend that the Collateral (as defined in the Pledge Agreement) secure the payment and performance of the New Loan; and

WHEREAS, SNBL USA and Lender desire to amend the Pledge Agreement to provide that the pledge secures the New Loan.

NOW, THEREFORE, in consideration of the premises and agreements, provisions and covenants herein contained, the parties hereto agree as follows:

1. Amendment to Pledge Agreement. The following amendments are made to the Pledge Agreement:

(a) Section 3. Section 3 of the Pledge Agreement is hereby amended and restated as follows:

“3. Secured Obligations. The Collateral secures the due and prompt payment and performance of:

(a) the obligations of the Pledgor from time to time arising under the Loan Agreement by and between Borrower and Lender in the original principal amount of Six Hundred Million Japanese Yen (¥600,000,000), dated as of June 27, 2018 (the “New Loan Agreement”), the Loan Agreement by and between Borrower and Lender in the original principal amount of Six Hundred Million Japanese Yen (¥600,000,000), dated as of December 27, 2017 (the “Existing Loan Agreement”), the Loan Agreement (if any) by and between Borrower and Lender in the original principal amount of Six Hundred Million Japanese Yen (¥600,000,000), dated as of June 30, 2017 (the “Second Prior Loan Agreement” and, together with the Loan Agreement, the “Prior Loan Agreements”), the Loan Agreement (if any), the Guaranty, this Agreement or otherwise with respect to the due and prompt payment of (i) the principal of and premium, if any, and interest on the Loans (including interest accruing during the pendency of any bankruptcy, insolvency, receivership or other similar proceeding, regardless of whether allowed or allowable in such proceeding), when and as due, whether at maturity, by acceleration, upon one or more dates set for prepayment or otherwise and (ii) all other monetary obligations, including fees, costs, attorneys’ fees and disbursements, reimbursement obligations, contract causes of action, expenses and indemnities, whether primary, secondary, direct or indirect, absolute or contingent, due or to become due, now existing or hereafter arising, fixed or otherwise (including monetary obligations incurred during the pendency of any bankruptcy, insolvency, receivership or other similar proceeding, regardless of whether allowed or allowable in such proceeding), of the Pledgor under or in respect of any of the Prior Loan Agreements (if any), the Existing Loan Agreement (if any), the New Loan Agreement, the Guaranty and this Agreement; and

(b) all other covenants, duties, debts, obligations and liabilities of any kind of the Pledgor under or in respect of any of the Prior Loan Agreements (if any), the Existing Loan Agreement (if any), the New Loan Agreement, the Guaranty, this Agreement or any other document made, delivered or given in connection with any of the foregoing, in each case whether evidenced by a note or other writing, whether allowed in any bankruptcy, insolvency, receivership or other similar proceeding, whether arising from an extension of credit, issuance of a letter of credit, acceptance, loan, guaranty, indemnification or otherwise, and whether primary, secondary, direct or indirect, absolute or contingent, due or to become due, now existing or hereafter arising, fixed or otherwise (all such obligations, covenants, duties, debts, liabilities, sums and expenses set forth in Section 3 being herein collectively called the “Secured Obligations”).”.

(b) Section 11(a). Section 11(a) of the Pledge Agreement is hereby amended and restated as follows:

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“(a) (i) Shin Nippon Biomedical Laboratories, Ltd. fails to make any payment when due under the Prior Loan Agreements, the Existing Loan Agreement or the New Loan Agreement or (ii) another “Event of Default” occurs under the Loan Agreement as such term is defined in any of the Prior Loan Agreements, another “Event of Default” occurs under the Existing Loan Agreement as such term is defined in the Existing Loan Agreement, or another “Event of Default” occurs under the New Loan Agreement as such term is defined in the New Loan Agreement), or;”.

2. Confirmation. SNBL USA hereby confirms and ratifies its obligations under, and the enforceability of, the Pledge Agreement (including without limitation the security interest granted under the Pledge Agreement upon and after the effectiveness of this Amendment) in accordance with its terms.

3. Representations and Warranties. SNBL USA represents and warrants to the Lender that the representations and warranties made by it in the Pledge Agreement are true and correct on and as of the date hereof, except to the extent that such representations and warranties specifically refer to an earlier date in which case such representations and warranties are true and correct as of such earlier date.

4. Counterparts. This Amendment may be executed in any number of counterparts, each of which shall be deemed an original as against any party whose signature appears thereon, and all of which shall together constitute one and the same instrument. Delivery of an executed counterpart of a signature page of this Amendment by telecopy or by .pdf shall be effective as delivery of a manually executed counterpart of this Amendment.

5. Governing Law. The validity, performance, construction, interpretation, and effect of this Amendment and any of the transaction contemplated hereby, shall be governed by and construed in accordance with the internal laws of the State of Washington (excluding its laws relating to conflicts of law).

6. Severability. Wherever possible each provision of this Amendment shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Amendment shall be prohibited by or invalid under such law, such provision shall be ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provision or the remaining provisions of this Amendment.

7. References. All references to the “Pledge Agreement” in any of the Prior Loan Agreements, Existing Loan Agreement, New Loan Agreement, Pledge Agreement and the Guaranty and Subordination Agreement dated December 27, 2017, as each is amended from time to time, by and among Borrower (as defined in the Pledge Agreement), SNBL USA and the Lender, shall mean the Pledge Agreement, as amended hereby and by the parties hereto from time to time. All other terms of the Pledge Agreement shall remain unchanged.

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8. CONSENT TO JURISDICTION; SERVICE OF PROCESS. SNBL USA AGREES THAT ANY ACTION OR PROCEEDING TO ENFORCE OR ARISING OUT OF THIS AMENDMENT MAY BE COMMENCED IN THE DISTRICT COURT OF THE UNITED STATES IN THE WESTERN DISTRICT OF WASHINGTON, AND SNBL USA WAIVES PERSONAL SERVICE OF PROCESS AND AGREES THAT A SUMMONS AND COMPLAINT COMMENCING AN ACTION OR PROCEEDING IN SUCH COURT SHALL BE PROPERLY SERVED AND SHALL CONFER PERSONAL JURISDICTION IF SERVED BY REGISTERED OR CERTIFIED MAIL TO SNBL USA, OR AS OTHERWISE PROVIDED BY THE LAWS OF THE STATE OF WASHINGTON OR THE UNITED STATES.

9. WAIVER OF JURY TRIAL. This section contains a jury waiver, arbitration clause, and a class action waiver. READ IT CAREFULLY. As permitted by applicable law, SNBL USA waives its rights to a trial before a jury in connection with any claim, dispute, or controversy arising between the parties hereto with respect to this Amendment, related agreements (all of the foregoing, a “Dispute”), and Disputes shall be resolved by a judge sitting without a jury. If a court determines that this provision is not enforceable for any reason and at any time prior to trial of the Dispute, but not later than 30 days after entry of the order determining this provision is unenforceable, any party shall be entitled to move the court for an order compelling arbitration and staying or dismissing such litigation pending arbitration.

Signature Page Follows

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IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to Pledge Agreement to be duly executed as of the day and year first above written.

Third Amendment to Pledge Agreement

Exhibit 99.15

Deed of Charge of Shares

Dated 14 September 2018

Between

(each referred to as a Party and collectively as the Parties).

Recitals

Agreed Terms

In this Deed:

Act means the Conveyancing and Law of Property Act (Chapter 61 of Singapore).

Additional Secured Shares has the meaning given in Clause 7(a).

Additional Share Charge Event means the breach of any the Financial Covenants as defined and set out in Clauses 21(4) of the Loan Agreement.

Business Day means a day (other than a Saturday, Sunday or public holiday) when banks in Singapore and Japan are open for business.

Companies Act means the Companies Act (Chapter 50 of Singapore).

Event of Default means the events set out in Clauses 23 of the Loan Agreement.

Further Deed has the meaning given in Clause 7.

Lender means each of the parties set out in Schedule B.

Loan has the meaning given in Recital C.

Loan Agreement has the meaning given in Recital C.

Majority Lenders means the Majority Security Holders as defined in the Security Holders Agreement.

Receiver means a receiver, Official Assignee or trustee in bankruptcy, in each case, appointed under this Deed.

Related Rights means the rights to receive:

Secured Liabilities means:

Secured Shares means: (i) 938,846 Ordinary Shares of WAVE; (ii) all present and future shares in the paid-up share capital of WAVE accruing to the aforementioned shares (including any share splits, consolidations or conversions); and (iii) their corresponding Related Rights, which are owned by the Chargor or held by any nominee on its behalf, or to be owned by it or to be held by any nominee on its behalf, and where the context permits, a reference to Secured Shares shall include:

Security Holders Agreement means the security holders agreement dated 14 September 2018 among the Chargor, the Lenders and the Security Agent.

Security Interest means any mortgage, charge, pledge, lien, security assignment or other security interest securing any obligation of any person or any other agreement or arrangement having a similar effect (including without limitation, title transfer and retention arrangements).

Security Period means the period beginning on the date of this Deed and ending on the date on which all the Secured Liabilities have been unconditionally and irrevocably paid and discharged in full.

Total Maximum Commitment Amount means the Total Maximum Commitment Amount as defined in Clause 1.34 of the Loan Agreement.

WAVE has the meaning given in Recital A.

In this Deed, unless otherwise specified:

The Chargor charges in favour of the Lenders by way of a first fixed charge:

The Chargor represents and warrants to the Lenders and the Security Agent that this Deed creates the Security it purports to create and is not liable to be amended or otherwise set aside on the bankruptcy of the Chargor or otherwise.

The Chargor has not received, or acknowledged notice of, any adverse claim by any person in respect of the Secured Shares or any interest in them.

There are no covenants, agreements, reservations, conditions, interests, rights or other matters whatsoever, that materially and adversely affect the Secured Shares.

The Chargor hereby irrevocably covenants and undertakes with each of the Lenders and the Security Agent the following.

so that the Security Agent may, at any time and without notice to the Chargor, complete and present those instruments of transfer and other documents to WAVE for registration.

Except with the prior written consent of all of the Majority Lenders, the Chargor must not

The Chargor shall not do, or permit to be done, any act or thing that would or might depreciate, jeopardise or otherwise prejudice the Security, or diminish the value of any of the Secured Shares and/or the Related Rights or the effectiveness of the Security.

take all such action as is available to the Chargor (including making all filings and registrations, including the registration with the Accounting and Corporate Regulatory Authority as mentioned in Clause 4.4.1) as may be necessary for the purpose of the creation, perfection, protection or maintenance of any charges conferred or intended to be conferred on the Lenders and/or the Security Agent by or pursuant to this Deed.

The Chargor shall use its best endeavours to enforce any rights and commence, continue or defend any proceedings relating to any of the Secured Shares which the Lenders and/or the Security Agent may require from time to time.

The Chargor shall, promptly on becoming aware of any of the same, notify the Security Agent in writing of

The Chargor shall:

in respect of the Loan Agreement and/or the Secured Shares.

After this Security has become enforceable, the Security Agent may pursuant to the decision of the Majority Lenders enforce all or any part of this Security in any manner and on the terms it sees fit, and take possession of and hold or dispose all or any part of the Secured Shares. The power of sale and other powers conferred by Section 24 of the Act, as amended by this Deed, will be immediately exercisable at any time after this Security has become enforceable.

No person (including a purchaser) dealing with the Security Agent or a Receiver or its agents will be concerned to enquire:

The Chargor must pay to the Lenders and/or the Security Agent, immediately on demand, the costs and expenses incurred by the Lenders and/or the Security Agent in connection with any such redemption and/or transfer of Security, including the payment of any stamp duties, principal, interest or other taxes.

If the Security is enforced at a time when no amount is due under the Loan Agreement but at a time when amounts may or will become due, the Security Agent (or the Receiver) may pay the proceeds of any recoveries effected by it into a suspense account.

Neither the Security Agent, the Lenders nor any of their nominees shall be liable to account as mortgagee in possession in respect of all or any of the Secured Shares, nor shall any of them be liable for any loss on realisation of, or for any neglect or default of any nature in connection with, all or any of the Secured Shares for which a mortgagee in possession might be liable as such.

The receipt of full consideration from a purchaser to the Security Agent, the Receiver or any of the Security Agent’s nominees shall be a conclusive discharge to that purchaser and, in making any sale or other disposal of any of the Secured Shares or in making any acquisition in the exercise of their respective powers, the Security Agent, the Receiver or any of the Security Agent’s nominees may do so for any consideration, in any manner and on any terms that it thinks fit.

Within 10 Business Days after the occurrence of an Additional Share Charge Event, the Chargor shall execute and deliver to the Security Agent a deed of charge of shares on terms substantively similar with this Deed or in such other form as required by the Lenders and/or the Security Agent, creating in favour of the Lenders a fixed charge over the following assets (Further Deed):

and the Chargor shall at its own expense promptly do all acts and execute all documents (including assignments, transfers, mortgages, charges, notices and instructions) as the Lenders and/or Security Agent may require (and in such form as Lenders and/or the Security Agent may require) to perfect the security created or intended to be created under the Further Deed or for the exercise of any rights, powers and remedies of the Lenders and/or the Security Agent provided by or pursuant to the Further Deed or by law and take all such action as is available to the Chargor (including making all filings and registrations) as may be necessary for the purpose of the creation, perfection, protection or maintenance of the security conferred or intended to be conferred on the Lenders and/or the Security Agent by or pursuant to the Further Deed.

Subject to the provisions of the Companies Act, the Security Agent may (for and on behalf of the Lenders) by deed, under seal or in writing under its hand remove any Receiver appointed by it and may, whenever it thinks fit, appoint a new Receiver in the place of any Receiver whose appointment may for any reason have terminated.

The Security Agent may (for and on behalf of the Lenders) fix the remuneration of any Receiver appointed by it and the maximum rate specified in Section 29(6) of the Act will not apply.

To the fullest extent allowed by law, any right, power or discretion conferred by this Deed (either expressly or impliedly) or by law on a Receiver may after this Security becomes enforceable be exercised by the Security Agent (for and on behalf of the Lenders) in relation to any Secured Shares without first appointing a Receiver or notwithstanding the appointment of a Receiver.

A Receiver may take immediate possession of, get in and collect any Secured Shares and/or Related Rights and require payment to him of any book debts or credit balance on any account.

A Receiver may settle, adjust, refer to arbitration, compromise and arrange any claim, account, dispute, question or demand with or by any person who is or claims to be a creditor of the Chargor or relating in any way to any Secured Shares and/or the Related Rights.

A Receiver may bring, prosecute, enforce, defend and abandon any action, suit or proceedings in relation to any Secured Shares and/or the Related Rights which he thinks fit.

A Receiver may give a valid receipt for any moneys and execute any assurance or thing which may be proper or desirable for realising any Secured Shares.

A Receiver may delegate his powers in accordance with this Deed.

Any moneys received by the Lenders, Security Agent or any Receiver after this Security has become enforceable must be applied in the following order of priority:

This Clause 10 is subject to the payment of any claims having priority over this Security. This Clause 10 does not prejudice the right of the Lenders and/or the Security Agent to recover any shortfall from the Chargor. The priority, application, timing and method of payment of any amounts among the Lenders and the Security Agent shall be determined in accordance with the relevant provisions of the Security Holders Agreement.

Each Party will pay its own costs and expenses relating to the negotiation and execution of this Deed. Subject as aforesaid, the Chargor must:

Any such person who is not a party to this Deed may rely on this Clause 10 and enforce its terms under the Contracts (Rights of Third Parties) Act (Chapter 53B) of Singapore.

The Lenders, Security Agent or any Receiver may delegate by power of attorney or in any other manner to any person any right, power or discretion exercisable by it under this Deed.

Any such delegation may be made upon any terms (including power to sub-delegate) which the Lenders, the Security Agent or any Receiver may think fit.

Neither the Lender, the Security Agent nor any Receiver will be in any way liable or responsible to the Chargor for any loss or liability arising from any act, default, omission or misconduct on the part of any delegate or sub-delegate except to the extent caused by its own gross negligence or wilful misconduct.

References in this Deed to the Lender, the Security Agent or a Receiver shall be deemed to include references to any delegate of the Lender, the Security Agent or the Receiver appointed in accordance with this Clause 12.

The Chargor must, at its own expense, take whatever action the Lender, the Security Agent or a Receiver may require for:

The requirements of this Clause 13 includes:

The Chargor irrevocably appoints the Security Agent, each Receiver and any of their respective delegates or sub-delegates to be its attorney or attorneys and in its name and otherwise on its behalf and as its act and deed to sign, seal, execute, deliver, perfect and do all deeds, agreements, instruments, acts and things which may be required (or which the Security Agent, the Receiver or any of their respective delegates or sub-delegates shall consider requisite) for carrying out any obligation imposed on the Chargor by or pursuant to this Deed, for carrying out any sale, transfer, assignment, lease or other dealings by the Security Agent, the Receiver or any of their respective delegates or sub-delegates, for getting control of the Secured Shares, and generally for enabling the Security Agent, the Receiver or any of their respective delegates of sub-delegates to exercise the respective powers, rights, authorities and discretions conferred on them or any of them by or pursuant to this Deed or by law and (without prejudice to the generality of the foregoing) to sign, seal and deliver and otherwise perfect any deed, assurance, agreement, assignment, charge conveyance, mortgage, transfer, instrument or act which it or he may deem proper in or for the purpose of exercising any of the such powers, rights, authorities and discretions.

The Chargor ratifies and confirms whatever any attorney does or purports to do pursuant to its appointment under this Clause.

The power of attorney granted under this Clause 14 is as regards the Security Agent, each Receiver and each of their delegates or sub-delegates (and as the Chargor hereby acknowledges) granted irrevocably and for value as part of the security constituted by this Deed to secure the interests of and the performance of the obligations owed to the Lenders and the Security Agent.

The Chargor must pay to the Lenders or discharge the Secured Liabilities in the manner provided for in the Loan Agreement.

This Security is continuing and will extend to the ultimate balance of all the Secured Liabilities, regardless of any intermediate payment or discharge in whole or in part.

This Security is in addition to and shall not be merged into or in any way excluded or prejudiced by any other Security Interest now or subsequently held by the Lenders for the Secured Liability.

The obligations of the Chargor under this Deed will not be affected by any act, omission, matter or thing which, but for this provision, would reduce, release or prejudice any of its obligations under this Deed or prejudice or diminish those obligations in whole or in part, including (whether or not known to it, the Lenders or the Security Agent), but not limited to the following:

Until all the Secured Liabilities have been irrevocably paid in full, the Lenders and/or the Security Agent may without affecting the liability of the Chargor under this Deed:

the Chargor will not, after a claim has been made or by virtue of any payment or performance by it under this Deed:

At the end of the Security Period:

The Lenders and/or the Security Agent may, at its discretion, grant time or other indulgence or make any other arrangement, variation or release with any person not being a party to this Deed (whether or not such person is jointly liable with the Chargor) in respect of any of the Secured Liabilities or of any other security for them without prejudice either to this Deed or to the liability of the Chargor for the Secured Liabilities.

Any notice given in connection with this Deed must be in Japanese.

Each Lender and/or the Security Agent may set off any liability of the Chargor to that Lender and/or the Security Agent against any liability of that Lender and/or the Security Agent to the Chargor to the extent permitted under the Loan Agreement.

Each Lender and/or the Security Agent is not obliged to exercise its rights under Clause 19.1. If, however, any Lender does exercise those rights that Lender and/or the Security Agent must promptly notify the Chargor of the set-off that has been made.

All payments made by the Chargor to the Lenders and/or the Security Agent under this Deed shall be made without any set-off, counterclaim, deduction or withholding (other than any deduction or withholding of tax as required by law).

Without detracting from the Lenders and the Security Agent’s rights of disclosure under any law, the Lenders, the Security Agent, each of their respective officers and agents may disclose in any manner howsoever, any information (which may include the Loan Agreement) relating to the Chargor or its relationship with the Lenders and/or the Security Agent (including without limitation, details of the Chargor’s payment obligations under the Loan Agreement):

This Clause supersedes any previous confidentiality undertaking given by any of the Lenders and/or the Security Agent in connection with this Deed prior to the date of this Deed.

All notices, requests, demands or other communications under or in connection with this Deed shall be given or made in writing and delivered by post or transmitted by electronic mail or facsimile to the relevant addresses and numbers specified below:

Any notice, request or other communication addressed to any Party hereto, whether despatched by hand or transmitted by electronic mail or facsimile, shall be effective only upon actual receipt by the addressee.

If any provision (or part of a provision) of this Deed is or becomes invalid, illegal or unenforceable, it shall be deemed modified to the minimum extent necessary to make it valid, legal and enforceable. If such modification is not possible, the relevant provision (or part of a provision) shall be deemed deleted. Any modification to or deletion of a provision (or part of a provision) under this clause shall not affect the legality, validity and enforceability of the rest of this Deed.

If a term of this Deed is or becomes illegal, invalid or unenforceable in any respect under any jurisdiction, that will not affect:

The rights and remedies of the Lenders and the Security Agent under this Deed:

The Chargor irrevocably and unconditionally:-

This Deed is governed by Singapore law.

In the event of any contradiction or inconsistency between any provisions in this Deed and any provision in the Loan Agreement and/or the Security Holders Agreement, the provisions in the Loan Agreement and/or the Security Holders Agreement shall prevail.

This Deed may be executed in any number of counterparts, each of which when executed and delivered shall constitute a duplicate original, but all the counterparts shall together constitute one Deed. No counterpart shall be effective until each Party has executed and delivered at least one counterpart.

In witness whereof this Deed has been executed as a deed on the date stated at the beginning.

In the presence of:

Schedule A

Loan Agreement

[omitted]

Schedule B

List of Lenders

Exhibit 99.16

FOURTH AMENDMENT TO PLEDGE AGREEMENT

THIS FOURTH AMENDMENT TO PLEDGE AGREEMENT is dated as of December 27, 2018 (this “Amendment”) and is made by and between SNBL U.S.A. Ltd., a Washington corporation (“SNBL USA”) and The Kagoshima Bank, Ltd. (“Lender”).

WHEREAS, on December 28, 2016, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Prior Loan”), evidenced by that certain Loan Agreement dated as of December 28, 2016 made by Borrower and payable to the order of Lender (the “Original Loan Agreement”);

WHEREAS, on June 30, 2017, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Second Prior Loan”), evidenced by that certain Loan Agreement dated as of June 30, 2017 made by Borrower and payable to the order of Lender (the “Second Prior Loan Agreement”); and

WHEREAS on December 27, 2017, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Third Prior Loan”), evidenced by that certain Loan Agreement dated as of December 27, 2017 made by Borrower and payable to the order of Lender (the “Third Prior Loan Agreement” and collectively and severally with the Original Loan Agreement and the Second Prior Loan Agreement, the “Prior Loan Agreements”);

WHEREAS, on June 27, 2018, the Lender made one or more loans to Borrower (as defined in the Pledge Agreement referenced below) in an aggregate amount not to exceed Six Hundred Million Japanese Yen (¥600,000,000) (the “Existing Loan”), evidenced by that certain Loan Agreement dated as of June 27, 2018 made by Borrower and payable to the order of Lender (the “Existing Loan Agreement”);

WHEREAS, Lender and SNBL USA are party to a Stock Pledge Agreement dated December 28, 2016, pursuant to which SNBL USA pledged all of its shares of stock issued by WaVe Life Sciences Pte. Ltd., a Singapore company, and certain other collateral to Lender to secure the Prior Loan, as amended by that certain Amendment to Pledge Agreement dated as of June 30, 2017, and Second Amendment to Pledge Agreement dated as of December 27, 2017, and Third Amendment to Pledge Agreement, dated as of June 27, 2018, by and between SNBL USA and Lender (as so amended, the “Pledge Agreement”);

WHEREAS, it is contemplated that on or about the date hereof, the Existing Loan will be repaid in full and Lender intends to make a new loan to Borrower in the principal amount of Six Hundred Million Japanese Yen (¥600,000,000) (the “New Loan” and collectively with the Prior Loan, the Second Prior Loan, the Third Prior Loan and the Existing Loan, the “Loans”) and the parties hereto intend that the Collateral (as defined in the Pledge Agreement) secure the payment and performance of the New Loan; and

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WHEREAS, SNBL USA and Lender desire to amend the Pledge Agreement to provide that the pledge secures the New Loan.

NOW, THEREFORE, in consideration of the premises and agreements, provisions and covenants herein contained, the parties hereto agree as follows:

1. Amendment to Pledge Agreement. The following amendments are made to the Pledge Agreement:

(a) Section 3. Section 3 of the Pledge Agreement is hereby amended and restated as follows:

“3. Secured Obligations. The Collateral secures the due and prompt payment and performance of:

(a) the obligations of the Pledgor from time to time arising under the Loan Agreement by and between Borrower and Lender in the original principal amount of Six Hundred Million Japanese Yen (¥600,000,000), dated as of December 27, 2018 (the “New Loan Agreement”); the Loan Agreement by and between Borrower and Lender in the original principal amount of Six Hundred Million Japanese Yen (¥600,000,000), dated as of June 27, 2018 (the “Existing Loan Agreement”); each Loan Agreement (if any) by and between Borrower and Lender in the original principal amount of Six Hundred Million Japanese Yen (¥600,000,000), dated as of June 30, 2017 (the “Second Prior Loan Agreement” and dated as if December 27, 2017 (the “Third Prior Loan Agreement”, which together with the Loan Agreement, and the Second Prior Loan Agreement, shall be referred to as the “Prior Loan Agreements”), the Loan Agreement (if any), the Guaranty, this Agreement or otherwise with respect to the due and prompt payment of (i) the principal of and premium, if any, and interest on the Loans (including interest accruing during the pendency of any bankruptcy, insolvency, receivership or other similar proceeding, regardless of whether allowed or allowable in such proceeding), when and as due, whether at maturity, by acceleration, upon one or more dates set for prepayment or otherwise and (ii) all other monetary obligations, including fees, costs, attorneys’ fees and disbursements, reimbursement obligations, contract causes of action, expenses and indemnities, whether primary, secondary, direct or indirect, absolute or contingent, due or to become due, now existing or hereafter arising, fixed or otherwise (including monetary obligations incurred during the pendency of any bankruptcy, insolvency, receivership or other similar proceeding, regardless of whether allowed or allowable in such proceeding), of the Pledgor under or in respect of any of the Prior Loan Agreements (if any), the Existing Loan Agreement (if any), the New Loan Agreement, the Guaranty and this Agreement; and

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(b) all other covenants, duties, debts, obligations and liabilities of any kind of the Pledgor under or in respect of any of the Prior Loan Agreements (if any), the Existing Loan Agreement (if any), the New Loan Agreement, the Guaranty, this Agreement or any other document made, delivered or given in connection with any of the foregoing, in each case whether evidenced by a note or other writing, whether allowed in any bankruptcy, insolvency, receivership or other similar proceeding, whether arising from an extension of credit, issuance of a letter of credit, acceptance, loan, guaranty, indemnification or otherwise, and whether primary, secondary, direct or indirect, absolute or contingent, due or to become due, now existing or hereafter arising, fixed or otherwise (all such obligations, covenants, duties, debts, liabilities, sums and expenses set forth in Section 3 being herein collectively called the “Secured Obligations”).”.

(b) Section 11(a). Section 11(a) of the Pledge Agreement is hereby amended and restated as follows:

“(a) (i) Shin Nippon Biomedical Laboratories, Ltd. fails to make any payment when due under the Prior Loan Agreements, the Existing Loan Agreement or the New Loan Agreement or (ii) another “Event of Default” occurs under the Loan Agreement as such term is defined in any of the Prior Loan Agreements, another “Event of Default” occurs under the Existing Loan Agreement as such term is defined in the Existing Loan Agreement, or another “Event of Default” occurs under the New Loan Agreement as such term is defined in the New Loan Agreement), or;”.

2. Confirmation. SNBL USA hereby confirms and ratifies its obligations under, and the enforceability of, the Pledge Agreement (including without limitation the security interest granted under the Pledge Agreement upon and after the effectiveness of this Amendment) in accordance with its terms.

3. Representations and Warranties. SNBL USA represents and warrants to the Lender that the representations and warranties made by it in the Pledge Agreement are true and correct on and as of the date hereof, except to the extent that such representations and warranties specifically refer to an earlier date in which case such representations and warranties are true and correct as of such earlier date.

4. Counterparts. This Amendment may be executed in any number of counterparts, each of which shall be deemed an original as against any party whose signature appears thereon, and all of which shall together constitute one and the same instrument. Delivery of an executed counterpart of a signature page of this Amendment by telecopy or by .pdf shall be effective as delivery of a manually executed counterpart of this Amendment.

5. Governing Law. The validity, performance, construction, interpretation, and effect of this Amendment and any of the transaction contemplated hereby, shall be governed by and construed in accordance with the internal laws of the State of Washington (excluding its laws relating to conflicts of law).

6. Severability. Wherever possible each provision of this Amendment shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Amendment shall be prohibited by or invalid under such law, such provision shall be ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provision or the remaining provisions of this Amendment.

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7. References. All references to the “Pledge Agreement” in any of the Prior Loan Agreements, Existing Loan Agreement, New Loan Agreement, Pledge Agreement and the Guaranty and Subordination Agreement dated as of June 27, 2018, as each is amended from time to time, by and among Borrower (as defined in the Pledge Agreement), SNBL USA and the Lender, shall mean the Pledge Agreement, as amended hereby and by the parties hereto from time to time. All other terms of the Pledge Agreement shall remain unchanged.

8. CONSENT TO JURISDICTION; SERVICE OF PROCESS. SNBL USA AGREES THAT ANY ACTION OR PROCEEDING TO ENFORCE OR ARISING OUT OF THIS AMENDMENT MAY BE COMMENCED IN THE DISTRICT COURT OF THE UNITED STATES IN THE WESTERN DISTRICT OF WASHINGTON, AND SNBL USA WAIVES PERSONAL SERVICE OF PROCESS AND AGREES THAT A SUMMONS AND COMPLAINT COMMENCING AN ACTION OR PROCEEDING IN SUCH COURT SHALL BE PROPERLY SERVED AND SHALL CONFER PERSONAL JURISDICTION IF SERVED BY REGISTERED OR CERTIFIED MAIL TO SNBL USA, OR AS OTHERWISE PROVIDED BY THE LAWS OF THE STATE OF WASHINGTON OR THE UNITED STATES.

9. WAIVER OF JURY TRIAL. This section contains a jury waiver, arbitration clause, and a class action waiver. READ IT CAREFULLY. As permitted by applicable law, SNBL USA waives its rights to a trial before a jury in connection with any claim, dispute, or controversy arising between the parties hereto with respect to this Amendment, related agreements (all of the foregoing, a “Dispute”), and Disputes shall be resolved by a judge sitting without a jury. If a court determines that this provision is not enforceable for any reason and at any time prior to trial of the Dispute, but not later than 30 days after entry of the order determining this provision is unenforceable, any party shall be entitled to move the court for an order compelling arbitration and staying or dismissing such litigation pending arbitration.

Signature Page Follows

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IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to Pledge Agreement to be duly executed as of the day and year first above written.

Fourth Amendment to Pledge Agreement