Ideaya Biosciences is trading at $39.77, up 12.11% in after-hours trading; no specific announcement explaining the October 21 move was identified.
- The latest newsroom item was an October 19 announcement of clinical data to be presented at ESMO 2026, October 23–27; that earlier news does not establish the cause of the surge.
- Major indexes finished higher, including the Nasdaq Composite at +1.07%, but broad-market strength alone does not explain the much larger move. No verified volume or trading-activity data was available.