Tim Clackson, Ph.D.

Tim Clackson, Ph.D., is President and Chief Executive Officer of Theseus Pharmaceuticals. Tim most recently served as President and Chief Technology Officer at Xilio Therapeutics, a privately held oncology company developing tumor-selective immunotherapies. From 1994 to 2018, Tim was with ARIAD Pharmaceuticals, where he was President of Research & Development and Chief Scientific Officer. He led the multi-disciplinary R&D team that internally discovered and developed five clinical-stage product candidates, including ICLUSIG® (ponatinib); ALUNBRIG® (brigatinib); and EXKIVITY® (mobocertinib). Prior to ARIAD, Tim was a postdoctoral research fellow at Genentech. He received his Ph.D. in biology from the University of Cambridge, and his BA in biochemistry from the University of Oxford.