Astellas and REGiMMUNE to Collaborate on New Vaccine Technology

TOKYO and MOUNTAIN VIEW, CA--(Marketwire - July 22, 2009) - REGiMMUNE Corporation today announced that Astellas Pharma Inc. and REGiMMUNE have entered into a collaboration agreement to jointly research and develop a novel vaccine-platform technology. The partnership will combine Astellas' broad range of capabilities in screening and developing natural source-derived compounds with REGiMMUNE's immune liposome technology. Terms of the agreement have not been disclosed.

"Our goal is to develop a potent vaccine-platform technology that enables effective vaccination with novel adjuvant and immune liposome technologies, increasing the efficiency of delivery to immune cells. Our approach will eliminate many of the current limitations for vaccine development," explained Haru Morita, CEO of REGiMMUNE. "This is particularly important for responding to new or changing virus strains. Astellas has a strong presence in immunology and is one of the largest vaccine distributors in Japan," Mr. Morita continued. "We believe this collaboration can produce a technology that will allow a rapid response to various viral outbreaks spreading around the world."

"We are pleased to initiate our first partnership with REGiMMUNE," stated Masafumi Nogimori, President and Chief Executive Officer of Astellas. "Disease prevention through timely and adequate vaccination is a key to maintaining human health. Astellas is committed to developing a new vaccine platform and this collaboration with REGiMMUNE will strengthen our position in this important area of disease prevention."

About Vaccines

Prophylactic vaccines need to elicit sufficient immune responses to protect individuals from the challenge by infectious agents. Most commonly, attenuated live viral particles are used to develop effective vaccines; however, development of live viral particles requires significant lead time and lengthy, costly manufacturing processes. While efforts have been made to develop improved adjuvants to enhance the potency of non-viral vaccines, Alum remains the only adjuvant approved by the U.S. FDA for use in humans. The Astellas-REGiMMUNE collaboration is expected to address these obstacles and provide a number of benefits over currently marketed products.

About REGiMMUNE

REGiMMUNE, with research and development operations in Tokyo, Japan, and Mountain View, CA, is a biotechnology company focused on the discovery, development and commercialization of immune-regulatory therapeutics to treat life-threatening and debilitating conditions including allergies, autoimmune diseases and transplantation. The company's proprietary platform technology, reVax, induces immune tolerance in an antigen-specific manner through pharmacological induction of regulatory T (Treg) cells. Treg cells are believed to play a central role in inducing and maintaining immune tolerance. Using its reVax technology, REGiMMUNE is developing a broad range of pipeline products. The lead compound, RGI-2001, which is in late preclinical stage, has the potential to become a first-in-class Treg-cell-inducing drug.

About Astellas

Astellas Pharma Inc., located in Tokyo, Japan, is a pharmaceutical company dedicated to improving the health of people around the world through the provision of innovative and reliable pharmaceutical products. The organization is committed to becoming a global category leader by combining outstanding R&D and marketing capabilities and continuing to grow in the world pharmaceutical market. For more information about Astellas Pharma Inc., please visit our website at www.astellas.com/en/.

Contact Information: REGiMMUNE US Media Contact: Debra Bannister +1-530-676-8001 http://www.regimmune.com