Torben Nissen

Torben Straight Nissen is an Executive Partner at Flagship Pioneering, the Cambridge, Massachusetts venture-creation firm behind companies such as Moderna, Generate:Biomedicines, and Rubius Therapeutics. He joined Flagship in 2016 and has focused on company formation and growth, including establishing the firm's Preemptive Health and Medicine initiative and providing executive leadership to portfolio companies including Rubius Therapeutics and Generate:Biomedicines. He brings more than 20 years of executive and R&D leadership across biotech and pharmaceuticals.

Before Flagship, Nissen was at Pfizer, where he headed Strategic Portfolio Management for the company's worldwide R&D organization, overseeing a portfolio of 300+ programs spanning discovery through Phase 2b across all major therapeutic areas. Earlier in his career he served as Chief Operating Officer at Ascendis Pharma and as Managing Director at Maxygen Inc. Within Flagship's portfolio he served as President of Rubius Therapeutics (roughly 2016–2019) during its build-out.

Since November 2022, Nissen has served as Chairman and CEO of Repertoire Immune Medicines, a Flagship company founded in 2019 that develops T-cell–based immune medicines for cancer and autoimmune disease. In 2025 he also became Chairman of the Board of Etiome, a new Flagship startup focused on preemptive healthcare and disease-state biomarkers. He continues to serve on the boards of Repertoire Immune Medicines and Flagship Labs 84.

Nissen holds a PhD in molecular biology and biochemical engineering from the Technical University of Denmark and Carlsberg Laboratories, and an MSc in chemical engineering from the Technical University of Denmark. He is a co-author or co-inventor on more than 100 publications and issued/published patents.

• Invests and builds through Flagship Pioneering's venture-creation model — companies are originated, founded, and capitalized inside the firm rather than sourced from external founders pitching cold.
• Focus on platform biotech with the potential to create entire product categories, consistent with Flagship's "pioneering" ethos (e.g., programmable immune medicine, preemptive health).
• Championed Flagship's Preemptive Health and Medicine strategy — the thesis that disease can be detected and intercepted before symptoms appear, embodied by the 2025 launch of Etiome.
• Strong bias toward immunology / immune medicine and therapeutics, reflecting his operating record at Repertoire (T-cell biology) and prior R&D-portfolio leadership at Pfizer.
• Values executive and R&D operating depth — his own path (Pfizer portfolio management, COO/MD roles, company president) signals he backs and staffs companies with rigorous drug-development discipline.