Our Team
A company of equals
Treeline is assembling a team of experts empowered to think and act creatively and collaboratively. We believe our colleagues should engage across disciplines and on equal footing with one another. Data and analysis, not titles nor reporting hierarchies, should drive our workflow and scientific decision making. We are a group of people who want to work hard, get stuff done, and measure ourselves by the clinical outcomes of our programs and how they benefit patients.

Mechanistic Biology
Our overriding obsession is committing to great targets for drug discovery. We give equal attention to the questions of disease dependency and therapeutic index (i.e., the difference between efficacious and toxic dose). We will not ask you, after the fact, to salvage a borderline project with positively biased experiments, biomarker hunting, or empiric combination work. Biologists at Treeline are the critical gatekeepers of our pipeline, from the moment of program inception.
Medicinal Chemistry
Despite the emergence of exciting new modalities (e.g., cell and gene therapy, complex biologics, etc.) we believe that small molecule medicinal chemistry will remain the backbone of the therapeutic armamentarium. We place high probability bets to focus on molecular targets amenable to traditional chemistry approaches, with increasingly heavy contributions from newer modalities. The chemists we recruit to Treeline are diligent, mindful of ADME as well as target engagement, and open-minded to advances in their own and adjacent fields. You won’t be replaced by a computer; rather, you will rely on computers to help design great drug candidates instead of taking a heads down, brute force approach.
Computational Science
In a world of hype and infinite use cases for computer-enabled drug discovery, our team stays focused on the highest probability applications of computational technology. We recognize that target selection, medicinal chemistry and clinical development are fundamentally too complicated to outsource to CROs and SABs. Computational approaches informed and refined by project specific, real-world experimental data are the most powerful. By joining a balanced and inter-disciplinary team, the north star of your career will move from the “use case” to clinical proof of efficacy.
Structural Biology & Protein Science
Our focus on protein structure and function is unrelenting. Whether you specialize in X-ray crystallography, SPR, biochemistry, NMR, novel assay development, mass spec, or scaled protein production, you will join a team that is passionate about pushing the envelope. Your assays and data will provide the oxygen for our medicinal chemistry and medicine design teams. We rely on you to match the right experimental system to the right question, and to help us prepare the major advances likely to come, but not guaranteed, by cryo-EM and emerging atomic biophysical technologies.
Our Founders

Joshua Bilenker, MD
Josh Bilenker is the co-founder and Chief Executive Officer of Treeline Biosciences. Previously, he was the CEO of Loxo Oncology at Lilly, a research and development group of Eli Lilly and Company. Dr. Bilenker joined Eli Lilly in 2019 after it acquired his prior company, Loxo Oncology, Inc. From 2006 to 2013, Dr. Bilenker worked as a life sciences venture capital investor at Aisling Capital LLC. From 2004 to 2006, Dr. Bilenker served as a medical officer at the US Food and Drug Administration, in the Office of Oncology. Dr. Bilenker trained at the University of Pennsylvania in internal medicine and medical oncology, earning board certification in these specialties. He received his M.D. from The Johns Hopkins University School of Medicine and his A.B. degree in English from Princeton University.

Jeffrey Engelman, MD, PhD
Jeff Engelman is the co-founder and Chief Scientific Officer of Treeline Biosciences. Previously, he was the Vice President and Global Head of Oncology at the Novartis Institutes for BioMedical Research, where he directed cancer drug discovery. Prior to Novartis, Dr. Engelman was Director of the Center for Thoracic Oncology and Molecular Therapeutic at Massachusetts General Hospital, where he studied responses to targeted therapies and mechanisms of resistance in lung cancer. He was also an Associate Professor at Harvard Medical School. Dr. Engelman received his B.A. in Chemistry from Northwestern University and his M.D. and Ph.D. from the Albert Einstein College of Medicine. He completed residency training in Internal Medicine at Brigham and Women's Hospital, a fellowship in Hematology/Oncology at Dana-Farber Cancer Institute and Massachusetts General Hospital, and postdoctoral research in the laboratory of Professor Lewis Cantley at Beth Israel Deaconess Medical Center.