SELLAS Life Sciences (SLS) 10-Q 2012 Q3 Quarterly report

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 Quarterly Report of Galena Biopharma, Inc., (the “Company”) on Form 10-Q for the period ended September 30, 2012 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned officers of the Company certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that to their 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 Company’s financial condition and result of operations.

/s/ Mark J. Ahn	/s/ Ryan M. Dunlap
Mark J. Ahn, Ph.D.	Ryan M. Dunlap
President and Chief Executive Officer	Director of Finance (Principal Financial and Accounting Officer
November 13, 2012	November 13, 2012