Flagship Pioneering and Repertoire® Immune Medicines Announce Agreement to Identify T Cell-Targeted Immune Medicines for Prostate Cancer Under Strategic Partnership with Pfizer

Repertoire and Pioneering Medicines, Flagship's in-house drug development unit, will jointly conduct research activities leveraging Repertoire's DECODE™ platform

CAMBRIDGE, Mass., Dec. 22, 2025 /PRNewswire/ -- Flagship Pioneering, a scientific innovation engine for transformative platforms and products, today announced a research program under its strategic collaboration with Pfizer whereby Flagship-founded Repertoire® Immune Medicines will identify and optimize TCR bispecifics for metastatic prostate cancer.

Pioneering Medicines, Flagship's in house drug discovery and development unit, is responsible for leading the strategic partnership with Pfizer, including driving the exploration process to rapidly surface potential drug development programs built on Flagship's diverse bioplatforms and modalities. The Repertoire agreement is the eighth program initiated under Flagship's strategic partnership with Pfizer announced in July 2023.

"Repertoire's DECODE platform uniquely maps the entire immune synapse, presenting enormous uncharted potential to discover new antigens capable of activating the immune system to fight cancer, and when coupled with Repertoire's immune medicine engineering technologies and capabilities, places us in a strong position to generate targeted medicines to engage them," said Torben Straight Nissen, Ph.D., Chairman and CEO of Repertoire and Executive Partner at Flagship Pioneering. "Guided by Pfizer's drug development expertise in oncology, we will apply our platform to uncover new potential T-cell targeted medicines." 

As many as one in five men with prostate cancer progress to metastatic disease with many going on to develop resistance to successive lines of therapy. T cell receptor (TCR) bispecifics have emerged as a promising immunotherapy with the potential to overcome several barriers associated with disease progression. The aim of the research program is to identify and develop an early optimized TCR bispecific lead that could provide durable disease control and reduced toxicity.

"This research program with Repertoire demonstrates both the continued momentum in our strategic alliance with Pfizer and the breadth of novel modalities our Flagship companies offer as a supply chain of potential therapeutic innovation," said Paul Biondi, Flagship Pioneering Managing Partner. "We have now collaborated on eight programs across multiple modalities and five therapeutic areas in our shared commitment with Pfizer to co-create a pipeline of novel candidates that have a potential to become differentiated medicines with greater precision, speed, and scale for the patients who need them most."

About Flagship Pioneering and Pioneering Medicines

Flagship Pioneering invents and builds platform companies, each with the potential for multiple products that transform human health, sustainability and beyond. Since its launch in 2000, Flagship has originated and fostered more than 100 scientific ventures, operating with $14 billion of assets under its direction as of its latest capital raise, announced in July 2024. The current Flagship ecosystem comprises more than 40 companies, including Foghorn Therapeutics, Generate Biomedicines, Inari, Indigo Agriculture, Lila Sciences, Moderna, Sana Biotechnology, Tessera Therapeutics and Valo Health.

Pioneering Medicines, Flagship Pioneering's in house drug development unit, is dedicated to conceiving and developing a broad portfolio of life-changing treatments for patients built from Flagship's innovative platforms. Harnessing the drug development expertise of its team together with the power of Flagship's multiple scientific platforms, Pioneering Medicines explores and identifies new product concepts which are then advanced jointly with Flagship's bioplatform companies. Within Flagship's Innovation Supply Chain partnerships, Pioneering Medicines works with external collaborators to apply its unique approach to partners' R&D priorities. These partnerships are highly co-creative strategic alliances that accelerate therapeutic innovation by bringing together partners spanning the full spectrum of drug discovery, development, and production.

About Repertoire® Immune Medicines

Repertoire Immune Medicines is discovering the unique immune codes that determine how we maintain health and respond to disease. Repertoire's proprietary DECODE™ platform uniquely elucidates the entire immune synapse, providing a comprehensive understanding of the interactions between T cell receptors and their cognate antigenic epitopes. Repertoire is translating these insights into new and potentially transformative T cell-targeted therapies for the treatment of cancer and autoimmune diseases.

Repertoire was founded in 2019 by Flagship Pioneering. Its team operates from sites in Cambridge, Massachusetts and Zurich. To learn more about Repertoire, please visit our website: www.repertoire.com and follow us on LinkedIn and X.

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SOURCE Flagship Pioneering