Pioneer Bio + Health Fund is Pioneer Fund's fund for founders at the earliest stages in biotechnology, healthcare and life sciences, writing pre-seed and seed checks. General Partner Dave Messina leads it, and more than 100 Y Combinator alumni who have built bio and health companies back it as venture partners. Its portfolio includes Gilgamesh Pharmaceuticals, Curebase, Medplum, Stepful, Assort Health, Biobot Analytics, Orange Health, Empirical Health, Talus Bio and Andromeda Surgical.