Marina Biotech Receives Notice of Allowance for U.S. Patent Related to Its Nucleic Acid-Peptide Drug Delivery Platform

BOTHELL, WA--(Marketwire - Sep 1, 2011) - Marina Biotech, Inc. (NASDAQ: MRNA), a leading nucleic acid-based drug discovery and development company, today announced that the U.S. Patent and Trademark Office (USPTO) has issued a Notice of Allowance for patent application U.S. 11/955,207 with claims that cover a library of over 1x10(15) novel peptides. The patent application is part of the Company's proprietary Trp Cage Library patent portfolio. This allowance strengthens the Company's nucleic acid-peptide drug delivery platform, and further expands the Company's patent protection for its comprehensive set of nucleic acid delivery technologies, which also include DiLA^2™, SMARTICLES^® and the tkRNAi^™ system.

"A primary advantage of this patented peptide library is the ability to rapidly screen and identify novel peptides that exhibit cell specific targeting characteristics for directed delivery of nucleic acid therapeutics," said Barry Polisky, Ph.D., Chief Scientific Officer of Marina Biotech. "Delivery remains a significant challenge in the nucleic acid therapeutic space, and peptides with high affinity and specificity are expected to be a fundamental component to developing delivery approaches to a wide spectrum of tissues and cell types. In addition, the library may also be exploited to screen for peptides that function as specific antagonists, agonists or generally exhibit drug like properties."

The Company's proprietary Trp Cage Phage Display Library (J Biol Chem. 2007 282(13):9813) is the subject of issued patents, U.S. patent 7,329,725; U.S. patent 7,704,953 and U.S. patent 7,772,189. The Trp Cage motif is highly structured allowing for the identification of peptides with high binding affinity for specific cell or tissue types, and avoids the limitations of low affinity and specificity often associated with linear peptide libraries. This technology is directly applicable to the Company's DiLA² and SMARTICLES delivery platforms as peptides are readily conjugated to the components of these delivery platforms. Peptides capable of directed delivery are expected to further improve the delivery efficiency of the Company's UNA and CRN substituted nucleic acid constructs, which have demonstrated in vivo activity and efficacy against targets in both normal/healthy and disease models, respectively.

A Notice of Allowance confirms the substantive examination of a patent application and will result in a final issuance of a U.S. patent after an administrative process is completed.

About Marina Biotech, Inc.
Marina Biotech is a biotechnology company, focused on the development and commercialization of RNA interference- (RNAi) and RNA-based therapeutics. The Marina Biotech pipeline currently includes a clinical program in Familial Adenomatous Polyposis (a precancerous syndrome) and two preclinical programs -- in bladder cancer and malignant ascites. Marina Biotech entered into an exclusive agreement with Debiopharm Group for the development and commercialization of the bladder cancer program. Marina Biotech's goal is to improve human health through the development of RNAi and RNA-based compounds and drug delivery technologies that together provide superior therapeutic options for patients. Additional information about Marina Biotech is available at http://www.marinabio.com.

Forward-Looking Statements
Statements made in this news release may be forward-looking statements within the meaning of Federal Securities laws that are subject to certain risks and uncertainties and involve factors that may cause actual results to differ materially from those projected or suggested. Factors that could cause actual results to differ materially from those in forward-looking statements include, but are not limited to: (i) the ability of Marina Biotech to obtain additional funding; (ii) the ability of Marina Biotech to attract and/or maintain manufacturing, research, development and commercialization partners; (iii) the ability of Marina Biotech and/or a partner to successfully complete product research and development, including preclinical and clinical studies and commercialization; (iv) the ability of Marina Biotech and/or a partner to obtain required governmental approvals; and (v) the ability of Marina Biotech and/or a partner to develop and commercialize products that can compete favorably with those of competitors. Additional factors that could cause actual results to differ materially from those projected or suggested in any forward-looking statements are contained in Marina Biotech's most recent periodic reports on Form 10-K and Form 10-Q that are filed with the Securities and Exchange Commission. Marina Biotech assumes no obligation to update and supplement forward-looking statements because of subsequent events.