Marina Biotech Completes Enrollment of Its First Cohort in the START-FAP Clinical Trial of CEQ508

BOTHELL, WA--(Marketwire - Apr 20, 2011) - Marina Biotech, Inc. (NASDAQ: MRNA), a leading RNAi-based drug discovery and development company, today announced the completion of enrollment in the first cohort of its START-FAP (Safety and Tolerability of An RNAi Therapeutic in Familial Adenomatous Polyposis), Phase 1b/2a clinical trial with CEQ508. This cohort makes up the first group in the Dose Escalation Phase consisting of three patients who will receive the starting and lowest dose level of 1x10(8) colony forming units (cfu)/day. The study drug is administered as an oral, daily drink for 28 days. Marina Biotech's Phase 1b/2a trial is an open-label, escalating-dose study of single daily doses of CEQ508 and will be conducted as a single center study in Boston, Massachusetts.

"I'm very pleased with the substantial progress we've made in patient enrollment and initiating first-in-man dosing in this cohort of FAP patients," stated Daniel C. Chung, MD, Principal Investigator of the START-FAP trial and gastroenterologist at Massachusetts General Hospital. "We're into our second week of drug administration with our first patient and anticipate dosing the subsequent two patients in this group in the coming weeks. The current lack of acceptable pharmaceutical options for this serious disease represents a significant unmet medical need."

Further, Marina Biotech today announced that the Australian Patent Office has issued a Notice of Allowance for patent application AU2005316458 with claims that broadly cover attenuated bacteria as a therapeutic platform for the delivery of short interfering RNA (siRNA) molecules that target disease-related genes (tkRNAi platform), including beta-catenin, whose dysregulation is implicated in the hyperproliferation and polyp formation characteristic of FAP, as well as being a key oncogene associated with the development of colorectal and other cancers. This allowed patent is part of a global patent portfolio with broad genus claims to the tkRNAi platform, which was developed and filed by the Beth Israel Deaconess Medical Center (BIDMC). Marina Biotech has an exclusive license to the tkRNAi platform from BIDMC. In addition, Marina Biotech owns U.S. and international patent applications that protect improvements to the tkRNAi platform for the generation of new drug candidates. In total, the global patent estate for the tkRNAi platform includes issued or allowed patents in Korea, Australia, and countries throughout Europe, and pending patent applications in the U.S., Canada and Japan.

About CEQ508

CEQ508 is the first drug candidate in a novel class of therapeutic agents utilizing the transkingdom RNA interference (tkRNAi) platform. CEQ508 comprises attenuated bacteria that are engineered to enter into dysplastic tissue and release a payload of short-hairpin RNA (shRNA), a mediator in the RNAi pathway. The shRNA targets the mRNA of beta-catenin, which is known to be dysregulated in classical FAP. CEQ508 is being developed as an orally administered treatment to reduce the levels of beta-catenin protein in the epithelial cells of the small and large intestine. Upon enrollment, patients will be placed in one of four dose-escalating cohorts. Following completion of the dose escalation phase, the trial plan calls for a stable-dose phase in which additional patients will receive the highest safe dose. CEQ508 will be administered daily in an oral suspension for 28 consecutive days. For more information please contact