Exhibit

[...***...] = CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT,

MARKED BY BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY

WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO

RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

1. CONTRACT ID CODE

PAGE OF PAGES

2. AMENDMENT/MODIFICATION NO.

0055

3. EFFECTIVE DATE

See Block 16C

4. REQUISITION/PURCHASE REQ. NO

OS232949

5. PROJECT NO. (If applicable)

6. ISSUED BY

CODE

ASPR-BARDA

7. ADMINISTERED BY (if other than Item 6)

CODE

ASPR-BARDA02

ASPR-BARDA

200 Independence Ave., S.W.

Room 640-G

Washington DC 20201

ASPR-BARDA

330 Independence Ave, SW, Rm G640

Washington DC 20201

8. NAME AND ADDRESS OF CONTRACTOR (No., street, county, State, and ZIP Code)

CHIMERIX, INC. 1377270

CHIMERIX, INC. 2505 MERIDIAN P

2505 MERIDIAN PKWY STE 340

DURHAM NC 277135246

(x)

9A. AMENDMENT OF SOLICITATION NO.

9B. DATED (SEE ITEM 11)

10A. MODIFICATION OF CONTRACT/ORDER NO.

HHSO100201100013C

CODE: 1377270

FACILITY CODE:

10B. DATED (SEE ITEM 13)

02/16/2011

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

The above numbered, solicitation is amended as set forth in item 14. The hour and date specified for receipt of Offers is extended is not extended.
Offers must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended by one of the following methods: (a) By completing
Items 8 and 15, and returning copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted; or (c) By
separate letter or telegram which includes a reference to the solicitation and amendment numbers, FAILURE OF YOUR ACKNOWLEDGMENT TO BE RECEIVED AT
THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR OFFER. If by
virtue of this amendment you desire to change an offer already submitted, such change may be made by telegram or letter, provided each telegram or letter makes
reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.



12. ACCOUNTING AND APPROPRIATION DATA (If Required) Net Increase: $2,340,571.00 See Schedule
13. THIS ITEM APPLIES ONLY TO MODIFICATIONS OF CONTRACTS/ORDERS, IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14
CHECK ONE	A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE CONTRACT ORDER NO IN ITEM 10A.
	B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, appropriation date, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(b).
	C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF
x	D. OTHER (Specify type of modification and authority) Bilateral: Mutual Agreement of the Parties.
E. IMPORTANT: Contractor ¨ is not ý is required to sign this document and return 0 copies to the issuing office
14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible) Tax ID Number: 33-0903395 DUNS Number: 121785997 A. The purpose of this bilateral modification is to incorporate the following changes into the contract: 1. Add cost growth funding in the amount of $2,340,571.00 (No Fixed Fee) for the purpose of funding additional time for the completion of Option 2/CLIN 0003 under Contract Number HHSO100201100013C. 2. As a result of adding additional funding to Option 2/CLIN 0003 under Contract Number HHSO100201100013, Option 2/CLIN 0003 is here by revised as follows: Continued …
Except as provided herein, all terms and conditions of the document referenced in Item 9A or 10A, as heretofore changed, remains unchanged and in full force and effect.
15A NAME AND TITLE OF SIGNER (type or print) M. Michelle Berrey CEO			16A NAME AND TITLE OF CONTRACTING OFFICER (Type or print) ETHAN J. MUELLER
15B CONTRACTOR/OFFEROR /s/ M. Michelle Berrey		15C DATE SIGNED 12/21/18		16B UNITED STATES OF AMERICA /s/ Ethan J. Mueller	16C. DATE SIGNED 1/10/19
(Signature of person authorized to sign)				(Signature of Contracting Officer)

NSN 7540-01-152-8070 STANDARD FORM 30 (REV 10-83)

Previous edition unusable Prescribed by GSA

FAR (48 CFR) 53.243

[...***...] = CERTAIN CONFIDENTIAL INFORMATION OMITTED



CONTINUATION SHEET		REFERENCE NO. OF DOCUMENT BEING CONTINUED HHSO100201100013C/0055				PAGE OF
						2		3
NAME OF OFFEROR OR CONTRACTOR CHIMERIX, INC. 1377270
ITEM NO. (A)	SUPPLIES/SERVICES (B)		QUANTITY (C)	UNIT (D)	UNIT PRICE (E)		AMOUNT (F)
	Total Estimated Cost: from $[...*...] By $2,340,571.00 to $[......]. No Change to the Total Fixed Fee of $[......]. Total Estimated Cost Plus Fixed Fee: From $[......] By $2,340,571.00 To $[......]. 3. This modification also results a change in the total amount of the contract from $[......] by $2,340,571.00 to $[......] as well as the following: Total Estimated Cost of the Contract: From $[......] By $2,340,571.00 To $[......]. No Change to the Total Fixed Fee of $[......]. Total Estimated Cost Plus Fixed Fee of the Contract: From $[......] By $2,340,571.00 To $[......]. 4. This modification hereby results in a increase in the total amount of the contract from $[......] By $2,340,571.00 to $[......]. 5. Block 15G of the SF 26, the amount of $[......] shall be changed to $[......]. 6. Also in Block 14 of the SF 26, the following CAN Number is added as follows: Appropriation Year: 2019; Object Class: 25016; CAN 1992019 $2,340,571.00. 7. The period of performance for Option 2/CLIN 0003 of Contract Number HHSO100201100013C is hereby changed from 1 September 2014 through 30 March 2019 to 1 September 2014 through 1 August 2019. 8. The Statement of Work under Contract Number HHSO100201100013 hereby remains unchanged. 9. For the Option 2/CLIN 0003, cost growth for this Modification 55, Total Estimated Cost (No Fixed Fee) - $2,340,571.00, Only, the following Indirect Cost Ceiling Rates are established for which Chimerix cannot seek reimbursement in excess of the following Indirect Cost Ceiling Rates: [......]% Fringe, [...*...]% G&A 10. The total amount, scope and period of performance of all other CLINs that are currently being performed under the contract remain unchanged. This modification does not exercise any unexercised Option CLINs under the contract and does not authorize any performance of efforts under any unexercised Option CLINs under the contract. In addition, the total amount, scope and period of performance of all unexercised Option CLINs under the contract remain unchanged. This modification also confirms that all activities under the base period of performance CLIN 0001 Continued ...

NSN 7540-01-152-8067 OPTIONAL FORM 336 (4-86)



CONTINUATION SHEET		REFERENCE NO. OF DOCUMENT BEING CONTINUED HHSO100201100013C/0055				PAGE OF
						3		3
NAME OF OFFEROR OR CONTRACTOR CHIMERIX, INC. 1377270
ITEM NO. (A)	SUPPLIES/SERVICES (B)		QUANTITY (C)	UNIT (D)	UNIT PRICE (E)		AMOUNT (F)
3	were completed as of 31 May 2013 and confirms that all activities under the Option 1/CLIN 0002 period of performance were completed as of 30 April 2015. B. This is a bilateral modification. All other terms and conditions of Contract Number HHSO100201100013C remain unchanged. Delivery Location Code: HHS HHS 200 Independence Avenue, SW Washington DC 20201 US FOB: Destination Period of Performance: 02/16/2011 to 08/01/2019 Change Item 3 to read as follows (amount shown is the obligated amount) : [...***...] $2,340,571.00 Reports and other Data Deliverables. Delivery: 11/30/2015 Amount: $16,951,226.00 Accounting Info: 2014.1992003.25106 Appr. Yr.: 2014 CAN: 1992003 Object Class: 25106 Funded: $0.00 Delivery: 06/30/2017 Amount: $535,016.00 Accounting Info: 2016.1992016.25103 Appr. Yr.: 2016 CAN: 1992016 Object Class: 25103 Funded: $0.00 Delivery 09/30/2018 Amount: $4,091,177.00 Accounting Info: 2018.1992018.25106 Appr. Yr.: 2018 CAN: 1992018 Object Class: 25106 Funded: $0.00 Delivery: 08/01/2019 Amount: $2,340,571.00 Accounting Info: 2019.1992019.25106 Appr. Yr.: 2019 CAN: 1992019 Object Class: 25106 Funded: $2,340,571.00