Exhibit (a)(1)(B)​

LETTER OF TRANSMITTAL
To Tender Shares of Common Stock
of
DECIBEL THERAPEUTICS, INC.
a Delaware corporation
at

$4.00 per share, payable in cash,
plus one non-tradeable contractual contingent value right per share,
which represents the contractual right to receive contingent payments of up to $3.50 per share
in cash upon the achievement of certain specified milestones within specified time periods

Pursuant to the Offer to Purchase
Dated August 25, 2023
by
SYMPHONY ACQUISITION SUB, INC.
a wholly owned subsidiary of
REGENERON PHARMACEUTICALS, INC.

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT
THE END OF THE DAY, ONE MINUTE AFTER 11:59 P.M., EASTERN TIME,
ON SEPTEMBER 22, 2023,
UNLESS THE OFFER IS EXTENDED OR EARLIER TERMINATED
(SUCH DATE AND TIME, AS IT MAY BE EXTENDED, THE “EXPIRATION DATE”).

The Depository for the Offer is:

COMPUTERSHARE

If delivering by UPS, FedEx or Courier: Computershare
Attn: Decibel Therapeutics
150 Royall Street, Suite V
Canton, MA 02021 Is using a USPS Service: Computershare
Attn: Decibel Therapeutics
P.O. Box 43011
Providence, RI 02940-3011

Delivery of this Letter of Transmittal to an address other than as set forth above will not constitute a valid delivery to the Depository (as defined below). You must sign this Letter of Transmittal in the appropriate space provided therefor below, with signature guaranteed, if required, and complete the Internal Revenue Service (“IRS”) Form W-9 included in this Letter of Transmittal or the appropriate IRS Form W-8, if required. The instructions set forth in this Letter of Transmittal should be read carefully before you tender any of your Shares (as defined below) into the Offer (as defined below).

DESCRIPTION OF SHARES TENDERED
Name(s) and Address(es) of Registered Holder(s) (Please fill in, if blank, exactly as name(s) appear(s) on certificate(s)) (Attach additional signed list if necessary)	Shares Tendered			Total Number of Shares Tendered*
	Certificate Number(s)	Total Number of Shares Represented by Certificate(s)	Book-Entry Shares Tendered
Total Shares	​	​	​
* Unless otherwise indicated, it will be assumed that all Shares described in the chart above are being tendered. See Instruction 4.

The Offer is not being made to (and no tenders will be accepted from or on behalf of) holders of Shares in any jurisdiction in which the making of the Offer or acceptance thereof would not be in compliance with the securities, “blue sky” or other laws of such jurisdiction.

This Letter of Transmittal is to be used by stockholders of Decibel Therapeutics, Inc. (“Decibel”) if (i) certificates (the “Certificates”) for shares of common stock, par value $0.001 per share, of Decibel (the “Shares”) are to be forwarded herewith or, (ii) unless an Agent’s Message (as defined in Section 2 of the Offer to Purchase) is utilized, if delivery of Shares is to be made by book-entry transfer to an account maintained by Computershare (the “Depository”) at The Depository Trust Company (“DTC”) (as described in Section 2 of the Offer to Purchase and pursuant to the procedures set forth in Section 3 thereof).

Additional Information if Certificates Have Been Lost, Destroyed or Stolen, or Are Being Delivered By Book-Entry Transfer

If Certificates you are tendering with this Letter of Transmittal have been lost, stolen, destroyed or mutilated, you should contact Computershare, in its capacity as transfer agent (the “Transfer Agent”), at 800-736-3001 to get the required paperwork to replace your certificate and participate in the Offer. You may be required to post a bond to secure against the risk that the Certificates may be subsequently recirculated. You are urged to contact the Transfer Agent immediately in order to receive further instructions, for a determination of whether you will need to post a bond and to permit timely processing of this documentation. See Instruction 11.

☐

CHECK HERE IF TENDERED SHARES ARE BEING DELIVERED HEREWITH.

NOTE:   SIGNATURES MUST BE PROVIDED BELOW.
PLEASE READ ACCOMPANYING INSTRUCTIONS CAREFULLY

Ladies and Gentlemen:

The undersigned hereby tenders to Symphony Acquisition Sub, Inc., a Delaware corporation (“Purchaser”) and a wholly owned subsidiary of Regeneron Pharmaceuticals, Inc., a New York corporation (“Regeneron”), the above described shares of common stock, par value $0.001 per share (the “Shares”), of Decibel Therapeutics, Inc., a Delaware corporation (“Decibel”), pursuant to Purchaser’s offer to purchase, subject to certain conditions, including the satisfaction of the Minimum Condition, as defined in the Offer to Purchase, any and all of the outstanding Shares, in exchange for $4.00 per Share, payable in cash, without interest and subject to reduction for any applicable withholding taxes (the “Cash Consideration”), plus one non-tradeable contractual contingent value right per Share that entitles the holder to receive up to an aggregate of $3.50 per contingent value right payable in cash, without interest and subject to reduction for any applicable withholding taxes, upon the achievement of certain clinical development and regulatory milestones for Decibel’s lead investigational candidate, DB-OTO, within specified time periods and in accordance with the terms and subject to the conditions of a contingent value rights agreement (each, a “CVR,” and which agreement, as it may be amended from time to time, the “CVR Agreement”) to be entered into with a rights agent (the “Rights Agent”) mutually agreeable to Regeneron and Decibel (the Cash Consideration plus one CVR, collectively, the “Offer Consideration”), upon the terms and subject to the conditions set forth in the Offer to Purchase, dated August 25, 2023 (the “Offer to Purchase”), and in this Letter of Transmittal (the “Letter of Transmittal” which, together with the Offer to Purchase, as each may be amended and supplemented from time to time, collectively constitute the “Offer”), receipt of which is hereby acknowledged.

Upon the terms and subject to the conditions of the Offer (and if the Offer is extended or amended, the terms of any such extension or amendment), and effective upon acceptance for payment of the Shares validly tendered herewith and not validly withdrawn prior to the Expiration Date (as defined in the Offer to Purchase) in accordance with the terms of the Offer, the undersigned hereby sells, assigns and transfers to or upon the order of Purchaser all right, title and interest in and to all of the Shares that are being tendered hereby (and any and all dividends, distributions, rights, other Shares or other securities issued or issuable in respect thereof on or after the date hereof (collectively, “Distributions”)) and irrevocably constitutes and appoints Computershare (the “Depository”) the true and lawful agent and attorney-in-fact of the undersigned with respect to such Shares (and any and all Distributions), with full power of substitution

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(such power of attorney being deemed to be an irrevocable power coupled with an interest in the Shares tendered by this Letter of Transmittal), to (i) deliver Certificates for such Shares (and any and all Distributions) or transfer ownership of such Shares (and any and all Distributions) on the account books maintained by The Depository Trust Company (“DTC”) or otherwise held in book-entry form, together, in any such case, with all accompanying evidences of transfer and authenticity, to or upon the order of Purchaser, (ii) present such Shares (and any and all Distributions) for transfer on the books of Decibel and (iii) receive all benefits and otherwise exercise all rights of beneficial ownership of such Shares (and any and all Distributions), all in accordance with the terms and subject to the conditions of the Offer.

By executing this Letter of Transmittal (or taking action resulting in the delivery of an Agent’s Message, as defined in the Offer to Purchase), the undersigned hereby irrevocably appoints each of the designees of Purchaser the attorneys-in-fact and proxies of the undersigned, each with full power of substitution, (i) to vote at any annual or special meeting of Decibel stockholders or any adjournment or postponement thereof or otherwise in such manner as each such attorney-in-fact and proxy or its, his or her substitute shall in its, his or her sole discretion deem proper with respect to, (ii) to execute any written consent concerning any matter as each such attorney-in-fact and proxy or its, his or her substitute shall in its, his or her sole discretion deem proper with respect to and (iii) to otherwise act as each such attorney-in-fact and proxy or its, his or her substitute shall in its, his or her sole discretion deem proper with respect to, all of the Shares (and any and all Distributions) tendered hereby and accepted for payment by Purchaser. This appointment will be effective if and when, and only to the extent that, Purchaser accepts such Shares for payment pursuant to the Offer. This power of attorney and proxy are irrevocable and are granted in consideration of the acceptance for payment of such Shares in accordance with the terms of the Offer. Such acceptance for payment shall, without further action, revoke any prior powers of attorney and proxies granted by the undersigned at any time with respect to such Shares (and any and all Distributions), and no subsequent powers of attorney, proxies, consents or revocations may be given by the undersigned with respect thereto (and, if given, will not be deemed effective). Purchaser reserves the right to require that, in order for the Shares to be deemed validly tendered, immediately upon Purchaser’s acceptance for payment of such Shares, Purchaser or its designees must be able to exercise full voting, consent and other rights with respect to such Shares (and any and all Distributions), including voting at any meeting of Decibel stockholders.

The undersigned hereby represents and warrants that the undersigned has full power and authority to tender, sell, assign and transfer any and all of the Shares tendered hereby (and any and all Distributions) and that, when the same are accepted for payment by Purchaser, Purchaser will acquire good and unencumbered title to such Shares (and such Distributions), free and clear of all liens, restrictions, charges and encumbrances and the same will not be subject to any adverse claims. The undersigned hereby represents and warrants that the undersigned is the registered owner of the Shares, or the Certificate(s) have been endorsed to the undersigned in blank, or the undersigned is a participant in DTC whose name appears on a security position listing as the owner of the Shares. The undersigned will, upon request, execute and deliver any additional documents deemed by the Depository or Purchaser to be necessary or desirable to complete the sale, assignment and transfer of the Shares tendered hereby (and any and all Distributions). In addition, the undersigned shall remit and transfer promptly to the Depository for the account of Purchaser all Distributions in respect of any and all of the Shares tendered hereby, accompanied by appropriate documentation of transfer, and, pending such remittance and transfer or appropriate assurance thereof, Purchaser shall be entitled to all rights and privileges as owner of each such Distribution and may withhold the entire Offer Consideration of the Shares tendered hereby or deduct from such Offer Consideration the amount or value of such Distribution as determined by Purchaser in its sole discretion.

All authority herein conferred or agreed to be conferred shall not be affected by, and shall survive the death or incapacity of the undersigned, and any obligation of the undersigned hereunder shall be binding upon the heirs, executors, administrators, personal representatives, trustees in bankruptcy, successors and assigns of the undersigned. Except as stated in the Offer to Purchase, this tender is irrevocable.

The undersigned hereby acknowledges that delivery of any Certificate shall be effected, and risk of loss and title to such Certificate shall pass, only upon the proper delivery of such Certificate to the Depository.

The undersigned understands that the valid tender of Shares pursuant to any of the procedures described in the Offer to Purchase and in the instructions hereto will constitute the undersigned’s acceptance

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of the terms and conditions of the Offer. Purchaser’s acceptance of such Shares for payment will constitute a binding agreement between the undersigned and Purchaser upon the terms and subject to the conditions of the Offer (and if the Offer is extended or amended, the terms and conditions of such extension or amendment). The undersigned recognizes that under certain circumstances set forth in the Offer, Purchaser may not be required to accept for exchange any Shares tendered hereby.

The undersigned understands that the CVRs will not be transferable except (a) upon death by will or intestacy; (b) by instrument to an inter vivos or testamentary trust in which the CVRs are to be passed to beneficiaries upon the death of the trustee; (c) pursuant to a court order; (d) by operation of law or without consideration in connection with the dissolution, liquidation, or termination of any corporation, limited liability company, partnership or other entity; (e) in the case of CVRs payable to a nominee, from a nominee to a beneficial owner (and, if applicable, through an intermediary) or from such nominee to another nominee for the same beneficial owner, in each case as allowable by the DTC; (f) if the holder is a partnership or limited liability company, by a distribution by the transferring partnership or limited liability company to its partners or members, as applicable (provided that such distribution does not subject the CVRs to a requirement of registration under the Securities Act of 1933, as amended (the “Securities Act”), or the Securities Exchange Act of 1934, as amended (the “Exchange Act”)); or (g) to Regeneron or Purchaser in connection with the abandonment of such CVR by the applicable holder.

Unless otherwise indicated under “Special Payment Instructions,” please issue a check for the Cash Consideration of all Shares purchased and, if appropriate, return Certificates not tendered or accepted for payment in the name(s) of the registered holder(s) appearing above under “Description of Shares Tendered.” Similarly, unless otherwise indicated under “Special Delivery Instructions,” please mail the check for the Cash Consideration of all Shares purchased and, if appropriate, return any Certificates not tendered or not accepted for payment (and any accompanying documents, as appropriate) to the address(es) of the registered holder(s) appearing above under “Description of Shares Tendered.” Subject to the terms and conditions of the CVR Agreement, please make all payments regarding CVRs, if and to the extent they become due and payable, as directed herein for payment of the Cash Consideration and enter in the CVR register to be maintained by the Rights Agent pursuant to the CVR Agreement the name(s) and address(es) appearing on the cover page of this Letter of Transmittal for each registered holder.

In the event that the boxes entitled “Special Payment Instructions” and “Special Delivery Instructions” are both completed, please issue the check for the Cash Consideration of all Shares purchased and, if appropriate, return any Certificates not tendered or not accepted for payment (and any accompanying documents, as appropriate) in the name(s) of, and deliver such check and, if appropriate, return any Certificates (and any accompanying documents, as appropriate) to, the person(s) so indicated. Unless otherwise indicated herein in the box entitled “Special Payment Instructions,” please credit any Shares tendered herewith by book-entry transfer that are not accepted for payment by crediting the account at DTC designated above. The undersigned recognizes that Purchaser has no obligation, pursuant to the “Special Payment Instructions,” to transfer any Shares from the name of the registered holder thereof if Purchaser does not accept for payment any of the Shares so tendered.

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SPECIAL PAYMENT INSTRUCTIONS (See Instructions 1, 5, 6 and 7)
To be completed ONLY if the check for the Cash Consideration of Shares accepted for payment and/or Certificates not tendered or not accepted for payment are to be issued in the name of someone other than the undersigned.
Issue check and/or certificates to:
Name:	(Please Print)
Address:
(Include Zip Code) (Taxpayer identification or Social Security No.)

SPECIAL DELIVERY INSTRUCTIONS (See Instructions 1, 5, 6 and 7)
To be completed ONLY if the check for the Cash Consideration of Shares accepted for payment and/or Certificates evidencing Shares not tendered or not accepted are to be mailed to someone other than the undersigned or to the undersigned at an address other than that shown above.
Mail check and/or Certificates to:
Name:	(Please Print)
Address:
(Include Zip Code)

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IMPORTANT STOCKHOLDER: YOU MUST SIGN BELOW (U.S. Holders: Please complete and return the IRS Form W-9 included below) (Non-U.S. Holders: Please obtain, complete and return IRS Form W-8BEN or other IRS Form W-8)
(Signature(s) of Holder(s) of Shares)
(Signature(s) of Holder(s) of Shares)
Dated:
Name(s):	(Please Print)
Capacity (full title) (See Instruction 5):
Address:	(Include Zip Code)
Area Code and Telephone No.:
Tax Identification or Social Security No. (See IRS Form W-9 included below):
(Must be signed by registered holder(s) exactly as name(s) appear(s) on Certificate(s) or on a security position listing or by person(s) authorized to become registered holder(s) by Certificates and documents transmitted herewith. If signature is by a trustee, executor, administrator, guardian, attorney-in-fact, agent, officer of a corporation or other person acting in a fiduciary or representative capacity, please set forth full title and see Instruction 5.)

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INSTRUCTIONS
FORMING PART OF THE TERMS AND CONDITIONS OF THE OFFER

1. Guarantee of Signatures.   No signature guarantee is required on this Letter of Transmittal (a) if this Letter of Transmittal is signed by the registered holder(s) (which term, for purposes of this Instruction, includes any participant in DTC’s systems whose name appears on a security position listing as the owner of the Shares) of Shares tendered herewith, unless such registered holder has completed either the box entitled “Special Payment Instructions” or the box entitled “Special Delivery Instructions” on this Letter of Transmittal or (b) if such Shares are tendered for the account of a financial institution (including most commercial banks, savings and loan associations and brokerage houses) that is a member in good standing of the Securities Transfer Agents Medallion Program or any other “eligible guarantor institution,” as such term is defined in Rule 17Ad-15 under the Securities Exchange Act of 1934, as amended (each, an “Eligible Institution”). In all other cases, all signatures on this Letter of Transmittal must be guaranteed by an Eligible Institution. See Instruction 5.

2. Requirements of Tender.   No alternative, conditional or contingent tenders will be accepted. In order for Shares to be validly tendered pursuant to the Offer, one of the following procedures must be followed:

For Shares held as physical certificates, the Certificates representing tendered Shares, a properly completed and duly executed Letter of Transmittal, together with any required signature guarantees, and any other documents required by this Letter of Transmittal, must be received by the Depository at one of its addresses set forth on the front page of this Letter of Transmittal before the Expiration Date.

For Shares held in book-entry form, either a properly completed and duly executed Letter of Transmittal, together with any required signature guarantees, or an Agent’s Message in lieu of this Letter of Transmittal, and any other required documents, must be received by the Depository at the appropriate address set forth on the front page of this Letter of Transmittal, and such Shares must be delivered according to the book-entry transfer procedures (as set forth in Section 3 of the Offer to Purchase) and a timely confirmation of a book-entry transfer of Shares into the Depository’s account at DTC (a “Book-Entry Confirmation”) must be received by the Depository, in each case before the Expiration Date.

The method of delivery of Shares, this Letter of Transmittal and all other required documents, including delivery through DTC, is at the election and risk of the tendering stockholder. Shares will be deemed delivered (and the risk of loss of Certificates will pass) only when actually received by the Depository (including, in the case of a book-entry transfer, by Book-Entry Confirmation). If delivery is by mail, then registered mail with return receipt requested, properly insured, is recommended. In all cases, sufficient time should be allowed to ensure timely delivery.

No fractional Shares will be purchased. By executing this Letter of Transmittal, the tendering stockholder waives any right to receive any notice of the acceptance for payment of Shares.

3. Inadequate Space.   If the space provided herein is inadequate, Certificate numbers, the number of Shares represented by such Certificates and/or the number of Shares tendered should be listed on a separate signed schedule attached hereto.

4. Partial Tenders (Not Applicable to Stockholders who Tender by Book-Entry Transfer).   If fewer than all the Shares represented by any Certificate delivered to the Depository are to be tendered, fill in the number of Shares which are to be tendered in the box entitled “Total Number of Shares Tendered.” In such case, a new Certificate for the remainder of the Shares represented by the old Certificate will be sent to the person(s) signing this Letter of Transmittal, unless otherwise provided in the appropriate box on this Letter of Transmittal, as promptly as practicable following the expiration or termination of the Offer. All Shares represented by Certificates delivered to the Depository will be deemed to have been tendered unless otherwise indicated.

5. Signatures on Letter of Transmittal; Stock Powers and Endorsements.

(a) Exact Signatures.   If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered hereby, the signature(s) must correspond with the name(s) as written on the face of the Certificates without alteration, enlargement or any change whatsoever.

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(b) Joint Holders.   If any of the Shares tendered hereby are held of record by two or more persons, all such persons must sign this Letter of Transmittal.

(c) Different Names on Certificates.   If any of the Shares tendered hereby are registered in different names on different Certificates, it will be necessary to complete, sign and submit as many separate Letters of Transmittal as there are different registrations of Certificates.

(d) Endorsements.   If this Letter of Transmittal is signed by the registered holder(s) of the Shares tendered hereby, no endorsements of Certificates or separate stock powers are required unless payment of the Cash Consideration is to be made, or Shares not tendered or not purchased are to be returned, in the name of any person other than the registered holder(s). Signatures on any such Certificates or stock powers must be guaranteed by an Eligible Institution.

(e) Stock Powers.   If this Letter of Transmittal is signed by a person other than the registered holder(s) of the Shares tendered hereby, Certificates must be endorsed or accompanied by appropriate stock powers, in either case, signed exactly as the name(s) of the registered holder(s) appear(s) on the Certificates for such Shares. Signature(s) on any such Certificates or stock powers must be guaranteed by an Eligible institution. See Instruction 1.

(f) Evidence of Fiduciary or Representative Capacity.   If this Letter of Transmittal or any Certificate or stock power is signed by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a corporation or other legal entity or other person acting in a fiduciary or representative capacity, such person should so indicate when signing, and proper evidence satisfactory to the Depository of the authority of such person so to act must be submitted. Proper evidence of authority includes a power of attorney, a letter of testamentary or a letter of appointment.

6. Stock Transfer Taxes.   If payment is to be made to, or if Certificate(s) for Shares not tendered or not accepted for payment are to be registered in the name of, any person(s) other than the registered holder(s), or if tendered Certificate(s) for Share(s) are registered in the name of any person(s) other than the person(s) signing this Letter of Transmittal, no amounts shall be paid in respect of such Share(s) unless evidence satisfactory to Decibel (or any successor entity) of the payment of any stock transfer or similar taxes (whether imposed on the registered holder(s) or such other person(s) or otherwise) payable as a result of the transfer to such other person(s), or exemption therefrom, is submitted.

7. Special Payment and Delivery Instructions.   If a check is to be issued for the Cash Consideration of any Shares tendered by this Letter of Transmittal in the name of, and, if appropriate, Certificates for Shares not tendered or not accepted for payment are to be issued or returned to, any person(s) other than the signer of this Letter of Transmittal or if a check and, if appropriate, such Certificates are to be returned to any person(s) other than the person(s) signing this Letter of Transmittal or to an address other than that shown in this Letter of Transmittal, the appropriate boxes on this Letter of Transmittal must be completed.

8. Tax Withholding.   Under U.S. federal income tax law, a tendering stockholder that is a United States person (as defined for U.S. federal income tax purposes, a “United States person”), and, if applicable, each other U.S. payee, is required to provide the Depository with a correct Taxpayer Identification Number (“TIN”) on IRS Form W-9, which is included herein, and to certify, under penalties of perjury, that such number is correct and that such stockholder or payee is not subject to backup withholding of federal income tax or otherwise establish a basis for exemption from backup withholding. Failure to provide the information on the IRS Form W-9 may subject the tendering stockholder or payee to backup withholding at the applicable rate, and such stockholder or payee may be subject to a penalty imposed by the IRS. The tendering stockholder or payee should write “Applied For” in the space for the TIN if a TIN has not been issued and the stockholder or payee has applied for a number or intends to apply for a number in the near future. If a TIN has been applied for and the Depository is not provided with a TIN before payment is made, the tendering stockholder or payee will be subject to backup withholding at the applicable rate. See the enclosed IRS From W-9 and the instructions thereto for additional information.

Certain stockholders or payees (including, among others, corporations and certain non-U.S. persons) may not be subject to backup withholding. Exempt stockholders or payees that are United States persons should furnish their TIN, check the appropriate box on the IRS Form W-9 and sign, date and return the IRS Form W-9 to the Depository in order to avoid backup withholding. A stockholder or other payee that is

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not a United States person may qualify as an exempt recipient by providing the Depository with a properly completed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or other appropriate IRS Form W-8, signed under penalties of perjury, attesting to such stockholder or payee’s foreign status or by otherwise establishing an exemption. An appropriate IRS Form W-8 may be obtained from the Depository or the IRS website (www.irs.gov).

Backup withholding is not an additional tax. Rather, the U.S. federal income tax liability of a person subject to backup withholding will be reduced by the amount of tax withheld. If backup withholding results in an overpayment of taxes, a refund or credit may be obtained from the IRS, provided that the required information is timely provided to the IRS.

9. Irregularities.   All questions as to the validity, form, eligibility (including time of receipt) and acceptance for payment of any tender of Shares will be determined by Purchaser, in its sole discretion, which determination shall be final and binding on all parties. However, stockholders may challenge Purchaser’s determinations in a court of competent jurisdiction. Purchaser reserves the absolute right to reject any and all tenders determined by it not to be in proper form or the acceptance for payment of which may, in the opinion of its counsel, be unlawful. Purchaser also reserves the absolute right to waive any defect or irregularity in the tender of any Shares of any particular stockholder, whether or not similar defects or irregularities are waived in the case of other stockholders. No tender of Shares will be deemed to have been validly made until all defects and irregularities have been waived or cured within such time as Purchaser shall determine. None of Regeneron, Purchaser, the Depository, the Information Agent or any other person will be under any duty to give notice of any defects or irregularities in tenders or incur any liability for failure to give any such notice. Purchaser’s interpretation of the terms and conditions of the Offer (including the Letter of Transmittal and the instructions thereto) will be final and binding.

10. Questions and Requests for Additional Copies.   The Information Agent may be contacted at the address and telephone number set forth on the last page of this Letter of Transmittal for questions and/or requests for additional copies of the Offer to Purchase, this Letter of Transmittal and other tender offer materials. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance. Such copies will be furnished promptly at Purchaser’s expense.

11. Lost, Stolen Destroyed or Mutilated Certificates.   If any Certificate has been lost, stolen, destroyed or mutilated, the stockholder should promptly notify Computershare at 800-736-3001. The stockholder will then be instructed as to the steps that must be taken in order to replace such Certificates. You may be required to post a bond to secure against the risk that the Certificates(s) may be subsequently recirculated. This Letter of Transmittal and related documents cannot be processed until the procedures for replacing lost, destroyed or stolen certificates have been followed. You are urged to contact Computershare immediately in order to receive further instructions and for a determination of whether you will need to post a bond and to permit timely processing of this documentation. This Letter of Transmittal and related documents cannot be processed until the procedures for replacing lost, destroyed, mutilated or stolen Certificates have been followed.

Certificates evidencing tendered Shares, or a Book-Entry Confirmation into the Depository’s account at DTC, as well as this Letter of Transmittal, properly completed and duly executed, with any required signature guarantees, or an Agent’s Message (if utilized in lieu of this Letter of Transmittal in connection with a book-entry transfer), and any other documents required by this Letter of Transmittal, must be received before the Expiration Date.

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The Depository for the Offer is:

COMPUTERSHARE

If delivering by UPS, FedEx or Courier: Computershare
Attn: Decibel Therapeutics
150 Royall Street, Suite V
Canton, MA 02021 Is using a USPS Service: Computershare
Attn: Decibel Therapeutics
P.O. Box 43011
Providence, RI 02940-3011

The Information Agent may be contacted at its address and telephone number listed below for questions and/or requests for additional copies of the Offer to Purchase, this Letter of Transmittal and other tender offer materials. You may also contact your broker, dealer, commercial bank, trust company or other nominee for assistance. Such copies will be furnished promptly at Purchaser’s expense.

The Information Agent for the Offer is:

Innisfree M&A Incorporated
501 Madison Avenue, 20th floor
New York, New York 10022
Stockholders may call toll free: (877) 456-3402
Banks and Brokers may call collect: (212) 750-5833