By Christy Santhosh
June 2 (Reuters) – Celcuity shares slumped 25%, set for their biggest one-day decline, on Tuesday after its experimental breast cancer treatment extended the period of time a patient lives without the disease worsening but underperformed a previous trial.
The drug, gedatolisib, in combination with Pfizer’s Ibrance and AstraZeneca’s endocrine therapy Faslodex was tested in advanced breast cancer patients with a confirmed mutation in a type of gene called PIK3CA.
The triple-drug combo extended progression-free survival (PFS) by 11.1 months compared to 5.6 months in patients who received Faslodex and Novartis’ Piqray.
Yet, Leerink analyst Andrew Berens said the “11 months PFS was inferior to that seen in the early-stage trials, which may disappoint some investors and pressure Celcuity shares.”
In a small early-stage trial with 30 patients, Celcuity’s drug combo showed 14.6 months PFS. The drug developer’s shares fell to $92.09 in afternoon trading.
CEO Brian Sullivan told Reuters that about a third of the patients enrolled in the early-stage trial had not received a type of therapy called CDK inhibitor, which was not representative of the more heavily pre-treated patient population in the late-stage trial.
CDKs are enzymes that regulate how cells grow and divide. CDK inhibitors prevent cancer cells from multiplying uncontrollably by stopping these enzymes.
The company projects “higher peak revenues” for gedatolisib than rival AstraZeneca’s Truqap and expects the treatment to become the new standard-of-care for these patients, Sullivan said.
The U.S. Food and Drug Administration is expected to make a decision on the therapy’s use in advanced breast cancer patients without a PIK3CA mutation by July 17.
Celcuity plans to submit a supplemental marketing application for gedatolisib to expand the label and broaden its use in advanced breast cancer patients irrespective of PIK3CA status.
(Reporting by Christy Santhosh in Bengaluru; Editing by Shilpi Majumdar)
