Meet the Founders

In 2021 co-founders Josh and Jeff joined forces, bringing their complementary skills, networks and passions together to build a new company with an ambitious model. They wanted access to leading-edge technologies and the resources to assemble a complete in-house discovery team. They believed the alternative – outsourced contract research and a one-and-done pipeline – would bring only incremental progress to the diseases they care most about.
Josh and Jeff are both medical oncologists with years of experience leading R&D teams.

Josh Bilenker, M.D.

CEO and Co-Founder

Josh founded Loxo Oncology, which successfully developed and commercialized three FDA-approved medicines until its acquisition by Eli Lilly and Company. His earlier roles in venture capital and at the FDA taught him to think backwards from regulatory approval. Generating clinical data worthy of this rare achievement takes careful planning and responsible capital formation.

Jeff Engelman, M.D. Ph.D.

CSO and Co-Founder

Jeff served as Global Head of Oncology at Novartis Institutes for BioMedical Research before co-founding Treeline. Prior to his industry career, he led an academic research lab and served as Director, Molecular Therapeutics and Director, Thoracic Oncology at Massachusetts General Hospital. Jeff is equally at home in the laboratory and the clinic. His understanding of the patient experience enters into every drug design decision he oversees. He loves data, hates cancer and seeks colleagues who care as much as he does.

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