Celcuity’s experimental PI3K/mTOR inhibitor gedatolisib cleared a Phase 3 primary endpoint in PIK3CA-mutant, HER-positive/HER2-negative, advanced breast cancer data, strengthening its case for FDA review while it also positions additional submissions. Separate reports also describe Celcuity gathering data that could support supplemental regulatory steps based on top-line results from another patient cohort. The Phase 3 readout gives Celcuity momentum while its gedatolisib decision from the FDA is still pending for a related HER-positive, HER2-negative, PIK3CA wild-type population. The company has signaled it may pursue a supplemental NDA after the PIK3CA-mutant cohort update. Collectively, the news reflects an ongoing PI3K pathway recalibration in HR+ breast cancer and the regulatory emphasis on subgroup efficacy where prior results may not have been uniform. For biotech stakeholders, the two-step strategy—maintaining attention on the current FDA decision while teeing up expansion filings—illustrates how companies hedge trial readouts into multiple regulatory pathways.