Signadori Bio

Signadori Bio is a Paris-based, preclinical-stage biopharmaceutical company developing a next-generation, off-the-shelf, in vivo engineered monocyte immunotherapy platform to treat solid tumors. Founded in 2025 through a collaboration between Sofinnova Partners and Gustave Roussy — Europe's leading oncology center — Signadori Bio was co-founded by Dr. Jean-Luc Perfettini and Professor Nathalie Chaput based on pioneering research into p21's novel role as a master regulator of myeloid anti-tumor functions, first described in a 2022 Nature Communications publication. The company's approach engineers monocytes directly in vivo using p21 biology, enabling these cells to infiltrate tumors, differentiate into macrophages with superior phagocytic activity, and stimulate adaptive immune responses — without requiring ex vivo cell manufacturing. This off-the-shelf approach aims to overcome the limitations of autologous CAR-T therapies and the immunosuppressive tumor microenvironment. The lead program, SiB-2101, is advancing toward lead candidate nomination. In May 2026, Signadori completed a seed extension bringing total funding to €11.1 million, with backing from Sofinnova Partners, Invivo Partners, and Taiho Ventures. The company is backed by exclusive worldwide licenses from Gustave Roussy.