European Investor
02 Jun 2026, 20:48
Celcuity Falls 23% Despite Strong Phase 3 Breast Cancer Data as Investors Lock In Gains
Shares of Celcuity (NASDAQ: CELC) fell 23% despite reporting highly positive Phase 3 results for gedatolisib in advanced breast cancer and receiving significant attention at the ASCO annual meeting.
The company announced detailed results from the Phase 3 VIKTORIA-1 trial in patients with HR-positive, HER2-negative, PIK3CA-mutated advanced breast cancer. Gedatolisib combined with fulvestrant and palbociclib reduced the risk of disease progression or death by 50% compared with alpelisib plus fulvestrant, while median progression-free survival nearly doubled to 11.1 months from 5.6 months. The treatment also achieved an objective response rate of 48.9% versus 26.0% for the comparator regimen.
The gedatolisib doublet also delivered strong results, reducing the risk of progression or death by 49% and extending median progression-free survival to 11.3 months. According to the company, the trial marked the first Phase 3 study to demonstrate superiority of one PI3K/AKT/mTOR pathway inhibitor over another in this patient population.
Safety results were also encouraging. Treatment discontinuation rates due to adverse events were lower for both gedatolisib regimens than for the alpelisib-based control arm, while rates of hyperglycemia and rash compared favorably to the comparator treatment.
Despite the strong clinical data, shares declined sharply following the announcement. Several biotechnology analysts noted that expectations had risen significantly ahead of the ASCO presentation and that investors were looking for clearer overall survival data, which remains immature. Market participants also focused on the company's upcoming FDA decision, with a PDUFA date of July 17, 2026, for gedatolisib in a related breast cancer indication.
Nevertheless, the results strengthened the case for gedatolisib as a potential new standard of care in advanced breast cancer and support Celcuity's plans for commercialization if regulatory approvals are obtained.
Shares of Celcuity (NASDAQ: CELC) fell 23% despite reporting highly positive Phase 3 results for gedatolisib in advanced breast cancer and receiving significant attention at the ASCO annual meeting.
The company announced detailed results from the Phase 3 VIKTORIA-1 trial in patients with HR-positive, HER2-negative, PIK3CA-mutated advanced breast cancer. Gedatolisib combined with fulvestrant and palbociclib reduced the risk of disease progression or death by 50% compared with alpelisib plus fulvestrant, while median progression-free survival nearly doubled to 11.1 months from 5.6 months. The treatment also achieved an objective response rate of 48.9% versus 26.0% for the comparator regimen.
The gedatolisib doublet also delivered strong results, reducing the risk of progression or death by 49% and extending median progression-free survival to 11.3 months. According to the company, the trial marked the first Phase 3 study to demonstrate superiority of one PI3K/AKT/mTOR pathway inhibitor over another in this patient population.
Safety results were also encouraging. Treatment discontinuation rates due to adverse events were lower for both gedatolisib regimens than for the alpelisib-based control arm, while rates of hyperglycemia and rash compared favorably to the comparator treatment.
Despite the strong clinical data, shares declined sharply following the announcement. Several biotechnology analysts noted that expectations had risen significantly ahead of the ASCO presentation and that investors were looking for clearer overall survival data, which remains immature. Market participants also focused on the company's upcoming FDA decision, with a PDUFA date of July 17, 2026, for gedatolisib in a related breast cancer indication.
Nevertheless, the results strengthened the case for gedatolisib as a potential new standard of care in advanced breast cancer and support Celcuity's plans for commercialization if regulatory approvals are obtained.