SELLAS Life Sciences shares fell 14.4% despite no disclosed failed trial or fresh company filing explaining the move. The coverage points to a timing gap around the pivotal Phase 3 REGAL study’s final event-driven milestone, where investors may be adjusting assumptions on when topline data will arrive. In May, the contract research organization reported that 78 of 80 prespecified events had occurred, leaving the company blinded as it continues through database lock and unblinding. A second readout is also tied to ongoing enrollment in the Phase 2 SLS009 program. The episode illustrates how event timing uncertainty—without new clinical disclosure—can still drive sharp re-pricing in pre-revenue biotech names near binary catalysts.