Marina Biotech Publishes Research on the Advantages of Its Novel UsiRNA Construct

BOTHELL, WA--(Marketwire - November 4, 2010) -  Marina Biotech, Inc. (NASDAQ: MRNA), a leading RNAi-based drug discovery and development company, today announced the publication of "Improved specificity of gene silencing by siRNAs containing unlocked nucleobase analogs" by Vaish et al., in the journal Nucleic Acids Research (published online November 2, 2010). This peer-reviewed manuscript describes the results of studies conducted by researchers at Marina Biotech demonstrating not only the high potency of UsiRNAs, but most notably, the elimination of off-target events as shown by microarray analyses, with no apparent off-target activity due to the UNA chemistry itself. Overall, the research demonstrates that a UsiRNA construct provides potential advantages over other typical siRNA constructs in the design of safe and highly efficacious RNAi-based therapeutics. 

"Publication of this manuscript demonstrates the utility of our UsiRNA technology over standard siRNAs," stated Dr. Barry Polisky, Chief Scientific Officer of Marina Biotech. "The UsiRNA construct addresses concerns about the potential for 'off-target' events that occur with standard siRNAs due to inadvertent loading of the passenger strand or because of poor target specificity of the guide strand. As described in the manuscript, our UsiRNA was associated with more than a 10-fold reduction in total off-target events compared to an unmodified siRNA."

The proprietary UsiRNA constructs are distinct from the standard siRNA constructs used by others in the industry. UsiRNAs are specifically designed to provide greater specificity for RNAi-based therapeutics. Substitution with UNA in the passenger strand (non-targeting strand) is intended to eliminate its participation in the RNAi process. Substitution in the guide strand (targeting strand) is intended to eliminate miRNA-like events, while preserving high siRNA-like activity. 

About Marina Biotech, Inc.
Marina Biotech (formerly known as MDRNA, Inc.) is a biotechnology company, focused on the development and commercialization of therapeutic products based on RNA interference (RNAi). The Marina Biotech pipeline currently includes a clinical program in Familial Adenomatous Polyposis (a precancerous syndrome) and two preclinical programs -- in hepatocellular carcinoma and bladder cancer. Marina Biotech's goal is to improve human health through the development of RNAi-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.

Contact Information:

Contacts:

Marina Biotech, Inc.
Pete Garcia
Chief Financial Officer
(425) 908-3603