Two drug regimens involving an experimental medicine from Celcuity halved the risk of death or disease progression in a late-stage trial in certain people with a type of advanced breast cancer. But the results still fell short of Wall Street expectations, sending the company’s shares plummeting by more than 20%.
Celcuity disclosed last month that its therapy, gedatolisib, succeeded in the latest part of a Phase 3 study evaluating the treatment in breast cancer patients with or without mutations to a gene called PIK3CA. Fresh data presented Tuesday at the American Society of Clinical Oncology’s annual meeting revealed the extent to which patients with those mutations benefited from treatment with Celcuity’s therapy.
In that study, “VIKTORIA-1,” Celcuity enrolled 350 people whose HR-positive, HER2-negative breast tumors were driven by PIK3CA mutations and who’d progressed after prior treatment. Trial participants were randomized to receive a “triplet” involving gedatolisib, hormone therapy and Pfizer’s Ibrance; a “doublet” pairing of gedatolisib and hormone treatment; or Novartis’ targeted therapy Piqray and a hormone drug.
Data presented Tuesday show both the “triplet” and “doublet” regimens halved the risk of disease progression or death. Those combinations held patients’ disease in check for a median of 11.1 months and 11.3 months, respectively, versus 5.6 months for patients treated with Piqray and hormone therapy.
