Exhibit 99.1 Relay Therapeutics Reports Fourth Quarter and Full Year 2023 Financial Results and Corporate Highlights Completed enrollment in initial RLY-2608 600mg + fulvestrant dose expansion cohort & initiated additional dose expansion cohorts with RLY-2608 400mg & 600mg Initiated RLY-2608 + fulvestrant + ribociclib triplet combination in PI3Kα-mutated HR+/HER2- metastatic breast cancer Approximately $750 million in cash, cash equivalents and investments at end of Q4 2023, expected to fund operations into ...