Gedatolisib with Fulvestrant - (VIKTORIA-1)

June 2, 2026: Celcuity Inc. (NASDAQ: CELC) reported detailed Phase 3 VIKTORIA-1 results from the PIK3CA-mutant cohort in adults with HR+/HER2- locally advanced or metastatic breast cancer after progression on/after a CDK4/6 inhibitor plus an aromatase inhibitor. Data are being presented as a late-breaking oral abstract at the ASCO Annual Meeting on June 2, 2026.

Gedatolisib + fulvestrant + palbociclib (“triplet”) vs alpelisib + fulvestrant: significantly improved BICR-assessed PFS (HR 0.50; 95% CI 0.37–0.68; p<0.0001), median PFS 11.1 vs 5.6 months; ORR 48.9% vs 26.0%; median DoR 15.7 vs 7.5 months.

Gedatolisib + fulvestrant (“doublet”) vs alpelisib + fulvestrant: PFS HR 0.51 (95% CI 0.33–0.79; descriptive p=0.0013), median PFS 11.3 vs 5.6 months; ORR 35.7%; median DoR 24.2 months.

Safety: Grade 3+ TRAEs included neutropenia (58.8% triplet), stomatitis, rash, hyperglycemia; discontinuations due to TRAEs were 2.6% (triplet), 3.8% (doublet), 7.1% (control). OS was immature with “promising trends.”

Regulatory catalysts: Celcuity plans an FDA supplemental NDA based on these data and subsequent submissions to other regulators. Separately, FDA Priority Review is ongoing for an NDA in the PIK3CA wild-type setting with a PDUFA goal date of July 17, 2026; the company cites potential FDA approval in Q3 2026.