Larkspur Biosciences is a Cambridge, Massachusetts precision-oncology company building first-in-class small molecule protein degraders that attack cancer cells where they are most vulnerable. Using its machine-learning-enabled LarkX platform to pinpoint 'cancer cell fitness' genes, Larkspur designs drugs that trigger tumor-intrinsic cell death and disrupt how cancers hide from the immune system. Its lead candidate, LRK-4189, degrades the lipid kinase PIP4K2C and entered first-in-human Phase 1 testing in December 2025 for microsatellite stable colorectal cancer.
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.