# Catherine Sabatos-Peyton

> Catherine Sabatos-Peyton is a cancer immunologist turned biotech CEO who runs Larkspur Biosciences, a Cambridge, Massachusetts company building small-molecule drugs that attack cancer's ability to hide from the immune system. As a Harvard PhD student she helped first describe TIM-3, now a major checkpoint protein; she later led discovery of the anti-TIM-3 antibody sabatolimab at CoStim and Novartis. In 2021 she stepped from the lab bench to the corner office, and now leads an all-female executive team whose lead drug, the PIP4K2C degrader LRK-4189, entered human trials in late 2025.

- **Role:** Chief Executive Officer at Larkspur Biosciences
- **Organizations:** Larkspur Biosciences, Novartis Institutes for BioMedical Research, CoStim Pharmaceuticals, Termeer Institute
- **Nationality:** American
- **Education:** B.S. in Biology, Fordham University, Fulbright Fellow (autoimmunity research), University of Oxford, Ph.D. in Immunology (Division of Medical Sciences), Harvard University, Postdoctoral fellowship, University of California, San Francisco (UCSF), Research fellowship, University of Bristol
- **Known for:** Member of the Harvard team that first described TIM-3, now a critical immune checkpoint and leukemic stem cell regulator, Led discovery of the first-in-class anti-TIM-3 antibody sabatolimab and advanced it to Phase 2/3 trials in AML and MDS, Built and led the Immune Modulation team at Novartis over 7 years spanning biologics and small molecules

## Career timeline

- **1996-1997** — Fulbright Fellow at the University of Oxford, studying the immune system's role in autoimmune disease
- **1997-2004** — Ph.D. in Immunology at Harvard; part of the team that first described TIM-3
- **2000s** — Postdoctoral and research fellowships at UCSF and the University of Bristol
- **2010s** — Directed immunology research at CoStim Pharmaceuticals; led discovery of the first-in-class anti-TIM-3 antibody sabatolimab
- **2014-2021** — Executive Director, Head of Immune Modulation at Novartis Institutes for BioMedical Research; advanced sabatolimab to Phase 2/3 in AML and MDS
- **2021** — Joined Larkspur Biosciences as Chief Executive Officer
- **2023-05** — Larkspur launched publicly with $35.5M in seed and Series A financing
- **2024** — Named a Termeer Institute Fellow (Class of 2024)
- **2025-12** — First patient dosed in Phase 1 trial of lead candidate LRK-4189, a PIP4K2C protein degrader

## Achievements

- Member of the Harvard team that first described TIM-3, now a critical immune checkpoint and leukemic stem cell regulator
- Led discovery of the first-in-class anti-TIM-3 antibody sabatolimab and advanced it to Phase 2/3 trials in AML and MDS
- Built and led the Immune Modulation team at Novartis over 7 years spanning biologics and small molecules
- Took Larkspur Biosciences from formation to a publicly launched company with $35.5M in financing
- Guided Larkspur's lead PIP4K2C degrader LRK-4189 into first-in-human trials
- Named a Termeer Institute Fellow, Class of 2024

## Latest updates

- **2025-12** — First patient dosed in the Phase 1 clinical trial of Larkspur's lead candidate LRK-4189, a first-in-class PIP4K2C protein degrader.
- **2025-09** — Featured in BiotechTV's 'Biotech CEO Sisterhood' discussing Larkspur's cancer cell fitness approach.
- **2024-04** — Named a Termeer Institute Fellow, Class of 2024.

## Links

- Website: https://larkspur.bio
- LinkedIn: http://www.linkedin.com/in/catherine-sabatos-peyton-3816695

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Profile page: https://yespress.io/catherine-sabatos-peyton
Published by YesPress — https://yespress.io
Last updated: 2026-06-14