Sergio Quezada

Prof. Sergio Quezada is Professor of Cancer Immunology and Immunotherapy at University College London (UCL). He earned his Biochemistry degree at the Pontificia Universidad Católica de Chile and completed his Ph.D. at Dartmouth Medical School before joining Nobel Laureate James Allison’s laboratory at Memorial Sloan Kettering Cancer Center, where he investigated the mechanisms underlying the anti‑tumour activity of anti‑CTLA‑4 antibodies.

Prof. Quezada’s research spans cancer immunology, regulatory T‑cell biology, the tumour microenvironment, and immune checkpoint blockade. His team uncovered the critical role of Fc receptors and the tumour milieu in shaping the activity of anti‑CTLA‑4 antibodies, and contributed to the development of next‑generation immune‑modulatory agents targeting VISTA, ICOS and CD25. He co‑led the creation of a best‑in‑class Treg‑depleting anti‑CD25 antibody, acquired by Roche for clinical evaluation in solid tumours. 

His group also investigates immune reactivity and evolutionary dynamics within human cancers to identify mechanisms of response and resistance to immunotherapy, insights that helped found Achilles Therapeutics, which developed personalised T‑cell therapies. Prof. Quezada served as the company’s Chief Scientific Officer from 2020–2025, shaping scientific and translational strategy. 

Building on this foundation, his team now integrates mechanistic immunology with antibody engineering and biotherapeutic development, including microenvironment‑guided design, testing and iterative refinement of antibody‑based therapies across cancer and immune‑mediated disease – an effort strengthened through collaborative work at the Francis Crick Institute.

Prof. Quezada has received honours including Dartmouth’s John W. Strohbern Medal, the Cancer Research Institute’s New Investigator Award, and Career Development and Senior Fellowships from Cancer Research UK. He is a Fellow of the European Academy for Cancer Sciences and the UK Academy of Medical Sciences.