Attached files

file filename
EX-31.2 - EX-31.2 - MERRIMACK PHARMACEUTICALS INCd125943dex312.htm
10-K - FORM 10-K - MERRIMACK PHARMACEUTICALS INCd125943d10k.htm
EX-32.2 - EX-32.2 - MERRIMACK PHARMACEUTICALS INCd125943dex322.htm
EX-21.1 - EX-21.1 - MERRIMACK PHARMACEUTICALS INCd125943dex211.htm
EX-23.1 - EX-23.1 - MERRIMACK PHARMACEUTICALS INCd125943dex231.htm
EX-31.1 - EX-31.1 - MERRIMACK PHARMACEUTICALS INCd125943dex311.htm
EX-10.20 - EX-10.20 - MERRIMACK PHARMACEUTICALS INCd125943dex1020.htm

Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report on Form 10-K of Merrimack Pharmaceuticals, Inc. (the “Company”) for the period ended December 31, 2015 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, Robert J. Mulroy, President and Chief Executive Officer of the Company, hereby certifies, pursuant to 18 U.S.C. Section 1350, that to his knowledge:

(1) the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

 

Date: February 26, 2016       /s/ Robert J. Mulroy
      Robert J. Mulroy
     

President and Chief Executive Officer

(Principal Executive Officer)