CAMBRIDGE, Mass, USA, and TOKYO, Japan, February 28, 2022Affinivax, Inc. (“Affinivax”) and Astellas Pharma Inc. (“Astellas”) today announced that they have entered into an agreement whereby Affinivax has reacquired the exclusive worldwide rights to ASP3772, a novel vaccine candidate targeting Streptococcus pneumoniae. In conjunction with the rights reacquisition by Affinivax, ASP3772 will be renamed AFX3772. Closing of the transaction is subject to clearance under the Hart-Scott Rodino Antitrust Improvements Act, which is expected in March or April of 2022. Under the terms of the parties’ new agreement, Astellas will receive a $65 million upfront payment and will be eligible to receive milestone payments and royalties tied to the clinical development and commercialization of ASP3772, as well as royalties tied to the commercialization of Affinivax’s next generation pneumococcal vaccine products designed to treat Streptococcus pneuomoniae.

“We are excited to regain exclusive, worldwide rights to ASP3772, our MAPS vaccine candidate for Streptococcus pneumoniae that has achieved positive Phase 2 clinical trial results and received FDA Breakthrough Therapy designation.  We believe ASP3772 has significant potential to address unmet needs in this important vaccine category. Following the closing of the transaction with Astellas, ASP3772 would become the most advanced vaccine candidate in Affinivax’s pipeline, along with other MAPS vaccine programs for bacterial pathogens, viral infections and cancer,” said Steven B. Brugger, CEO of Affinivax. “We are very appreciative of the trust that Astellas placed in Affinivax and our novel MAPS technology platform when we signed our original agreement in 2017, and their commitment to our partnership since then.”

“For Astellas, this decision is based on the strategic prioritization of our R&D pipeline to other core therapeutic areas and drug modalities,” said Naoki Okamura, Chief Strategy Officer and Chief Financial Officer, Chief Business Officer at Astellas. “Our work with Affinivax has been consistent with our vision of being a partner of choice for biotech companies advancing innovative technology platforms that can deliver promising new drugs to prevent and treat diseases and help patients worldwide. Our collaboration on the MAPS vaccine and technology platform has enabled the clinical validation and advancement of a promising new vaccine for Streptococcus pneumoniae for adults and infants that offers the potential to improve human health.”

Developed using Affinivax’s proprietary MAPS™ (Multiple Antigen-Presenting System) technology platform, ASP3772 is designed to elicit both B-cell (antibody) and T-cell immune protection against Streptococcus pneumoniae. ASP3772 includes 24 pneumococcal polysaccharides, as well as two conserved pneumococcal proteins. The results from the Phase 2 clinical trial demonstrated that ASP3772 was well tolerated. ASP3772 also exhibited an antibody response to each of the 24 polysaccharides, as well as an additional antibody response to the conserved pneumococcal proteins.

The U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy designation for ASP3772 for the prevention of pneumonia and invasive disease caused by Streptococcus pneumoniae serotypes included in ASP3772 in adults aged 50 years and older. The FDA decision is informed by the results of the Phase 2 clinical data. The FDA’s Breakthrough Therapy process is designed to expedite the development and review of drugs that are intended to treat a serious or life-threatening condition.


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