CELC REVTORPYK sNDA: PIK3CA-Mutant Breast Cancer

Celcuity (NASDAQ: CELC) filed a supplemental New Drug Application (sNDA) on August 26 asking the FDA to expand REVTORPYK (gedatolisib) into HR+/HER2- advanced breast cancer with a PIK3CA mutation. Approval would extend the drug from the PIK3CA wild-type label it won on July 14 to nearly every HR+/HER2- patient, because about 40% of that subtype carries a PIK3CA mutation. The stock closed at $92.27.

The filing rests on the PIK3CA-mutant cohort of the Phase 3 VIKTORIA-1 trial, which randomized 350 patients. Gedatolisib plus fulvestrant and palbociclib, the triplet, cut the risk of progression or death by 50% versus Novartis’ alpelisib (Piqray) plus fulvestrant, with a hazard ratio of 0.50 (p<0.0001) and median progression-free survival of 11.1 months versus 5.6 months. The doublet, gedatolisib plus fulvestrant, produced a hazard ratio of 0.51 and median PFS of 11.3 months. Objective response rates were 49% for the triplet and 36% for the doublet, with median response durations of 15.7 and 24.2 months.

This is a head-to-head win over the incumbent. Alpelisib has led the PIK3CA-mutant segment since 2019, and VIKTORIA-1 is the first trial to beat it directly. REVTORPYK blocks all four class I PI3K isoforms plus mTORC1 and mTORC2, a broader hit than alpelisib’s PI3K-alpha-only action. The tradeoff is the known PI3K-class safety burden: stomatitis, rash, and hyperglycemia stay on the label, with stomatitis in 72% of triplet patients.

Beyond the label expansion, Celcuity is already running VIKTORIA-2, a pair of first-line trials testing gedatolisib with palbociclib plus either fulvestrant or letrozole in treatment-naive patients, and a Phase 1/2 prostate cancer study combining the drug with darolutamide. The sNDA is the first step in a plan to make gedatolisib available across the full HR+/HER2- setting, not just the second-line niche.

The investor context is that Celcuity is six weeks past its first approval and already filing to roughly double its addressable market, yet the market has not rewarded the science. REVTORPYK won its wild-type approval July 14 and the stock sold off afterward, a move covered in this REVTORPYK analysis, and the NCCN’s 16-day Category 1 listing did not reverse it as detailed in the NCCN adoption coverage. The worry is a valuation built on a flawless launch with no revenue yet.

What to watch: the FDA has not set a PDUFA date, and Celcuity has not said whether it will seek priority review. The wild-type launch is on track for late Q3 2026. A six-month priority review would put a decision in early 2027. Here is how an sNDA works.

Source: Celcuity press release, August 26, 2026