Nassim Usman

Nassim Usman is an organic chemist turned biotech operator who runs Totus Medicines, an Emeryville, California company using a DNA-encoded covalent library platform (OmniDEL) paired with machine learning to build small-molecule drugs against targets long considered undruggable. He took the CEO chair in December 2023 alongside a $66 million Series B, and its lead drug, TOS-358, is the first covalent PI3K-alpha inhibitor in the clinic. Over three decades he has moved from bench chemistry on RNA and ribozymes to the top jobs at Sirna Therapeutics, Catalyst Biosciences, and Principia Biopharma, plus a stint as a venture investor at Morgenthaler Ventures.