A hazard ratio of 0.50 (95% CI: 0.37 to 0.68; p<0.0001), from the PIK3CA mutant cohort of the Phase 3 VIKTORIA-1 trial, anchors the supplemental New Drug Application Celcuity Inc. (Nasdaq: CELC) filed with the FDA on August 26, 2026, for REVTORPYK (gedatolisib) in HR+/HER2-, PIK3CA mutant locally advanced or metastatic breast cancer. The math reconciles: median progression-free survival of 11.1 months on the REVTORPYK-triplet (gedatolisib, fulvestrant, palbociclib) versus 5.6 months on alpelisib plus fulvestrant, consistent with the stated 50% reduction in risk of disease progression or death. The Minneapolis-based company already holds an FDA approval for REVTORPYK in the same breast cancer indication without the PIK3CA mutation, cleared July 14, 2026.
VIKTORIA-1 PIK3CA mutant cohort: both regimens
Of 701 subjects enrolled in VIKTORIA-1, 350 with confirmed PIK3CA mutations were randomized 3:3:1 across the gedatolisib-triplet, the alpelisib-plus-fulvestrant control arm, and the gedatolisib-doublet. All efficacy figures below are reported from the trial.
| Regimen | Median PFS | HR vs. control | 95% CI | ORR | Median DOR |
|---|---|---|---|---|---|
| REVTORPYK-triplet | 11.1 mo | 0.50 | 0.37-0.68; p<0.0001 | 49% | 15.7 mo |
| REVTORPYK-doublet | 11.3 mo | 0.51 | 0.33-0.79; p=0.0013 (descriptive) | 36% | 24.2 mo |
| Alpelisib + fulvestrant | 5.6 mo | ref |
The doublet arm: lower ORR (36% vs 49%), longer DOR (24.2 months vs 15.7 months). The triplet arm carries the stronger statistical anchor; the doublet p-value of 0.0013 is described as descriptive.
Safety data from both arms was consistent with the previously reported PIK3CA wild-type cohort. Stomatitis occurred in 72% of triplet patients (Grade 3 in 22%) and 58% of doublet patients (Grade 3 in 12%). Rash affected 30% of triplet patients (Grade 3 in 6%) and 40% of doublet patients (Grade 3 in 5%). Hyperglycemia was observed in 46% on the triplet (Grade 3: 0.9%) and 57% on the doublet (Grade 3: 1.8%).
Addressable population and differentiation claim
HR+/HER2- breast cancer accounts for approximately 70% of all breast cancer cases; about 40% of that group carry PIK3CA mutations, according to the filing. REVTORPYK inhibits all four class I PI3K isoforms (alpha, beta, delta, gamma) and both mTOR complexes, mTORC1 and mTORC2, with downstream inhibition of multiple effectors including AKT. If approved, the company said REVTORPYK would be the first therapy for advanced breast cancer with a PIK3CA mutation to carry that mechanism of action.
Igor Gorbatchevsky, MD, Chief Medical Officer of Celcuity, said the filing could make REVTORPYK available to all HR+/HER2- advanced breast cancer patients regardless of PIK3CA mutation status. Brian Sullivan, CEO and co-founder, said the company intends to work with the FDA collaboratively on the application. No regulatory decision timeline was stated.