Adrian Rawcliffe

Adrian “Ad” Rawcliffe joined Flagship Pioneering in 2026 as CEO-Partner and Chief Executive Officer of Etiome. Ad is a seasoned biotechnology leader with more than two decades of experience steering high-growth organizations through scientific, strategic, and financial inflection points.

Ad most recently served as CEO of Adaptimmune Therapeutics, where he led the registration of the first engineered TCR T-cell therapy for a solid tumor, orchestrated multiple strategic partnerships and M&A activities, and raised approximately $1.3B through a blend of capital markets and business development. Prior, as CFO, he guided Adaptimmune through its IPO and helped grow the company to more than 500 employees.

Before Adaptimmune, Ad spent more than 15 years at GSK in senior global roles, including SVP of Finance for North American Pharmaceuticals, SVP of Worldwide Business Development and R&D Finance, where he pioneered GSK’s first option-based R&D partnership model and led numerous external innovation and venture initiatives, and Managing Partner and President of SR One.

He currently serves as a non‑executive director of WAVE Life Sciences.

Ad began his career as a chartered accountant with PwC and holds a B.Sc. degree in Natural Sciences from the University of Durham, UK.