Exhibit 10.77

Execution Version

AMENDMENT No. 2 TO SECURITIES PURCHASE AGREEMENT

THIS AMENDMENT (this “Amendment”) to that certain Securities Purchase Agreement (the “Purchase Agreement”), dated as of December 22, 2011, by and between Socius CG II, Ltd., a Bermuda exempted company (the “Investor”), and Marina Biotech, Inc., a Delaware corporation (the “Company”), is made as of January 12, 2012. Capitalized terms used but not defined in this Amendment shall have the meanings ascribed to such terms in the Purchase Agreement.

WHEREAS, the Company and the Investor desire to amend the Purchase Agreement, pursuant to Section 6.3 of the Purchase Agreement, in the manner set forth in this Amendment.

NOW, THEREFORE, in consideration of the mutual covenants contained in this Amendment and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the Company and the Investor hereby agree as follows:

““Common Shares” includes the Warrant Shares and the Additional Investment Shares.”

““DWAC Shares” means all Common Shares or other shares of Common Stock issued or issuable to Investor or any Affiliate, successor or assign of Investor pursuant to any of the Transaction Documents, including without limitation any Warrant Shares and Additional Investment Shares, all of which shall be (a) issued in electronic form, (b) freely tradable by Investor and legend free and without restriction on resale, and (c) timely credited by Company to the specified Deposit/Withdrawal at Custodian (DWAC) account with DTC under its Fast Automated Securities Transfer (FAST) Program or any similar program hereafter adopted by DTC performing substantially the same function, in accordance with irrevocable instructions issued to and countersigned by the Transfer Agent, in the form attached hereto as Exhibit C or in such other form agreed upon by the parties.”

““Placement Agent Fee Shares” means the shares of Common Stock issued in payment of the Placement Agent Fee.”

“(i)   If at any time from the applicable Tranche Notice Date through the related Tranche Closing Date (in both cases inclusive), a current, valid and effective Registration Statement and Prospectus is not properly available for use to permit the lawful public resale by the Investor of all Common Shares underlying the Warrant (including the portion of the Warrant vesting on the applicable Tranche Notice Date) and underlying the Additional Investment Right with respect to the applicable Tranche Notice Date then held by the Investor or any of its Affiliates, or any such Common Shares would not be immediately freely tradable by Investor or any of its Affiliates.”

“(ix)   a current, valid and effective Registration Statement and Prospectus shall be properly available for use, at all times from the applicable Tranche Notice Date through the related Tranche Closing Date (in both cases inclusive), to permit the lawful public resale by the Investor of all Common Shares underlying the Warrant (including the portion of the Warrant vesting on the applicable Tranche Notice Date) and underlying the Additional Investment Right with respect to the applicable Tranche Notice Date then held by the Investor or any of its Affiliates; “

“(f)   Issuance of the Securities. The Securities and the Placement Agent Fee Shares are duly authorized and, when issued and paid for in accordance with the applicable Transaction Documents, and subject to, and in reliance on, the representations, warranties, covenants and agreements made herein by the Investor, will be duly and validly issued, fully paid and nonassessable, and subject to Section 5.14, free and clear of all Liens. The Company has reserved from its duly authorized capital stock a number of shares of Common Stock and Preferred Stock for issuance of the Securities and the Placement Agent Fee Shares at least equal to the number of Securities and Placement Agent Fee Shares which could be issued pursuant to the terms of this Agreement based on the then-current anticipated exercise price(s) of the Warrant.”

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IN WITNESS WHEREOF, the parties have caused this Amendment to be duly executed by their respective authorized signatures as of the date first set forth above.