Dicerna Pharmaceuticals Announces Second DsiRNA Therapeutic Oncology Candidate, Achieves Development Milestone

Company Receives Milestone Payment from Kyowa Hakko Kirin

Dicerna Pharmaceuticals Announces Second DsiRNA Therapeutic Oncology Candidate, Achieves Development Milestone

<0> Dicerna PharmaceuticalsDouglas M. Fambrough, Ph.D., 617-612-6205CEOorPure CommunicationsMichele Rozen, 617-730-8284 </0>

, a second generation RNA interference (RNAi) company developing novel therapeutics utilizing its proprietary Dicer Substrate Technology™ and Dicer Substrate siRNA (DsiRNA) molecules, announced today that Kyowa Hakko Kirin Co., Ltd. (TSE: 4151) (KHK) has recognized the successful achievement of an in vivo activity milestone in the development of its second collaborative therapeutic oncology candidate. This achievement triggers an undisclosed milestone payment to Dicerna.

Dicerna has a research collaboration and license agreement with KHK for the research, development and commercialization of DsiRNA pharmaceuticals and drug delivery systems for therapeutic targets in oncology. In December 2011, Dicerna announced that their first oncology target was moving from the research stage into development and that a second oncology program had been initiated with an additional gene target.

“At the end of last year, we were very pleased to announce an important validation of the in vivo efficacy of our DsiRNA technology ,” said Douglas M. Fambrough, Ph.D., chief executive officer of Dicerna. “This work demonstrated its significant potential in the development of cancer therapeutics by targeting a gene that had been of field-wide interest for many years and considered to be among the classical undruggable pharmacology targets. This latest achievement shows the excellent progress that has been made in targeting yet another oncology related gene. Our partnership with KHK has been very fruitful, resulting in two promising announced programs and additional programs in earlier stages.”

“We were particularly pleased with the speed with which this milestone was reached for our second candidate,” said Etsuo Ohshima, Ph.D., managing officer and vice president, head, research division at KHK. “It reflects the collaborative activity of our respective teams, and it also represents a unique feature of RNAi technology and its facility in bringing forward highly potent therapeutic candidates. As has been the case throughout this collaboration, this in vivo success was achieved utilizing Dicerna’s DsiRNA molecule in combination with our proprietary drug delivery system.”

Dicer is a critical enzyme involved in the RNAi gene silencing cascade and acts as the natural initiation point for this pathway by processing double-stranded RNA so that it can be used for gene silencing. Dicer then delivers these modified small RNA molecules to the mature gene silencing complex. Dicerna’s synthetic Dicer Substrate siRNA (DsiRNA) molecules are 25 or more base pairs in length and are processed by Dicer. By utilizing this distinct early entry point into the pathway, DsiRNA molecules have greater potency and longer duration of action than other RNAi approaches. In addition, DsiRNA molecules have enhanced delivery potential because their structure creates a natural conjugation point for cellular targeting agents.

Dicerna Pharmaceuticals is a private, venture-backed RNAi-focused biopharmaceutical company developing novel therapeutic agents and related drug delivery systems in oncology and other disease areas based on its proprietary Dicer Substrate Technology™ platform and Dicer Substrate siRNA (DsiRNA) molecules. Dicer Substrate Technology™ is a second generation RNAi approach that results in greater potency, longer duration of action and enhanced delivery potential, differentiating it from other RNAi approaches. Dicerna has a major alliance with Kyowa Hakko Kirin for DsiRNA pharmaceuticals and drug delivery systems focused in oncology, immunology and inflammation. The company also has a partnership with Ipsen to research and develop novel DsiRNA therapeutics with targeted delivery in oncology and endocrinology. Dicerna is based in Watertown, Massachusetts. For more information, please visit .

Kyowa Hakko Kirin Co., Ltd. is a leading biopharmaceutical company in Japan. It had a new start in October 2008 following the merger of Kyowa Hakko Kogyo Co., Ltd. and Kirin Pharma Company, Limited, with the aim of becoming a global specialty pharmaceutical company that creates innovative new drugs. Kyowa Hakko Kirin is focusing its core business areas of oncology, nephrology and immunology to create new value in the life sciences and to contribute to the health and well-being of people around the world. For more information, visit .