Stock Markets June 2, 2026 10:41 AM

Celcuity Shares Tumble After Full VIKTORIA-1 PIK3CA Data Fails to Meet Street's Lofty Expectations

Clinically significant Phase 3 results and a pending FDA review were not enough to prevent a heavy selloff as absolute efficacy metrics disappointed investors

By Caleb Monroe CELC

Celcuity PLC stock plunged 23.8% in morning trading after the company disclosed full efficacy and safety outcomes from the PIK3CA-mutant cohort of its Phase 3 VIKTORIA-1 trial. Although gedatolisib-based regimens met the study's primary endpoint with statistically significant reductions in risk of progression or death versus alpelisib plus fulvestrant, the absolute median progression-free survival figures came in below prior benchmarks and the market reacted by repricing the equity sharply downward.

Celcuity Shares Tumble After Full VIKTORIA-1 PIK3CA Data Fails to Meet Street's Lofty Expectations
CELC

Key Points

  • Celcuity stock fell 23.8% after full efficacy and safety data from the PIK3CA-mutant cohort of Phase 3 VIKTORIA-1 were presented at ASCO in Chicago.
  • Gedatolisib-based regimens reduced the risk of progression or death by about 50% versus alpelisib plus fulvestrant and met the primary endpoint, but absolute median progression-free survival for the active arms (11.1 and 11.3 months) was below the 11.6 months seen in Phase 1b.
  • The control arm (alpelisib plus fulvestrant) underperformed historical benchmarks, recording 5.6 months versus prior 7.4 months, complicating commercial interpretation; analysts largely maintained positive stances but adjusted targets modestly.

Celcuity PLC shares dropped 23.8% in morning trading following release of comprehensive efficacy and safety data from the PIK3CA-mutant cohort of the Phase 3 VIKTORIA-1 study. The data were presented as a late-breaking oral session at the American Society of Clinical Oncology Annual Meeting in Chicago.

The trial results showed that gedatolisib-containing combination regimens reduced the risk of disease progression or death by roughly 50% when compared with the comparator arm of alpelisib plus fulvestrant. Those outcome differences were statistically significant and satisfied the trial's primary endpoint.

Despite meeting its primary goal, investor focus centered on the absolute median progression-free survival, where the gedatolisib triplet arm recorded a median of 11.1 months and the gedatolisib doublet arm recorded 11.3 months. Both figures fell short of the 11.6 months observed in the earlier Phase 1b study, tempering enthusiasm for the commercial outlook.

Complicating the commercial read-through was the underperformance of the control arm versus historical levels. The alpelisib plus fulvestrant arm posted a median progression-free survival of 5.6 months in VIKTORIA-1, notably below the 7.4 months seen in prior data. Analysts highlighted that both the active and comparator arms deviating from earlier benchmarks blurred the clarity of how these results will translate in the market.

Market reaction contrasted with broader U.S. equity action, suggesting the move was company-specific. During the session the S&P 500 was essentially flat at +0.1%, the Nasdaq also rose +0.1%, and the Dow Jones edged down -0.1%.

Analyst responses were mixed but leaned toward continued support for the stock. Stifel reiterated its Buy rating with a $175 price target. Leerink adjusted its target modestly downward to $155 from $160 but maintained an Outperform rating. The wider analyst consensus remains at Strong Buy, with price targets spanning $157 to $189.

Adding regulatory context, the FDA has already granted Priority Review for gedatolisib in the PIK3CA wild-type indication and set a PDUFA decision date of July 17, 2026. The Phase 3 PIK3CA-mutant cohort results discussed at ASCO relate to a separate subgroup within the VIKTORIA-1 program.

Investors appear to have been pricing in a higher upside than the data delivered, a dynamic consistent with a "buy the rumor, sell the news" pattern. Celcuity had rallied over the past year to a 52-week high of $151.02, and the post-release decline pushed the stock back toward $93.76 as the market reassessed the near-term commercial opportunity ahead of the regulatory milestone.


What this means

While the VIKTORIA-1 PIK3CA-mutant cohort results are statistically significant and supportive of a regulatory filing, the market reaction underscores how absolute efficacy benchmarks and comparative historical performance can overshadow relative risk reductions when high valuation expectations are already embedded in the share price.

The selloff was driven by company-specific clinical detail rather than broader market forces, and analysts retained generally favorable ratings despite trimming or reiterating targets in light of the new data.


Conference and market notes

The data were disclosed at a late-breaking oral session at the American Society of Clinical Oncology Annual Meeting in Chicago. There were no major macro releases or Federal Reserve commentary identified that materially moved the market during the session in which the stock declined.

Risks

  • Absolute efficacy measures in the VIKTORIA-1 PIK3CA-mutant cohort came in below previous Phase 1b benchmarks, which could pressure commercial adoption and valuation - impacting the healthcare and biotech sectors.
  • The control arm underperformed its historical performance, creating uncertainty about how trial outcomes translate to real-world benefit and commercial potential - affecting investor confidence in Celcuity specifically and oncology developers more broadly.
  • Market expectations and prior share-price appreciation created vulnerability to a "buy the rumor, sell the news" reaction, meaning future swings could be driven by sentiment around clinical detail rather than broader market conditions - relevant to equity markets and biotech-focused investors.

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