Celcuity Inc. announced that the first patient has been dosed in its Phase 3 clinical trial, VIKTORIA-1, evaluating gedatolisib plus fulvestrant with and without palbociclib for the treatment of patients with HR+/HER2- advanced breast cancer. Gedatolisib, the company's lead therapeutic candidate, is a potent, reversible dual inhibitor that selectively targets all Class 1 PI3K isoforms and mTOR. In July 2022, the U.S. Food and Drug Administration (FDA) granted Breakthrough Therapy designation to gedatolisib for the treatment of HR+/HER2- advanced breast cancer that has progressed after treatment with a CDK4/6 inhibitor in combination with an aromatase inhibitor.

This designation allows for more intensive guidance from the FDA and a potentially accelerated review time if relevant criteria are met. Gedatolisib previously received Fast Track designation from the FDA in January 2022. Dosing the first patient satisfies the primary closing condition of a $100 million private placement agreement that the company signed in May of this year.

Investors participating in the private placement include Venrock Healthcare Capital Partners, Commodore Capital, New Enterprise Associates (NEA), RA Capital Management, Soleus Capital, and Brian Sullivan, the Company's Chief Executive Officer and Co-Founder. Under the terms of the private placement, investors will purchase common stock, preferred stock that may be convertible into common stock, and warrants exercisable for common stock. VIKTORIA-1 is a Phase 3 open-label, randomized clinical trial to evaluate the efficacy and safety of gedatolisib in combination with fulvestrant with or without palbociclib in adults with HR+/HER2- advanced breast cancer whose disease has progressed after prior CDK4/6 therapy in combination with an aromatase inhibitor.

The clinical trial will enroll subjects regardless of PIK3CA status while enabling separate evaluation of subjects according to their PIK3CA status. Subjects who meet eligibility criteria and do not have confirmed PI3KCA mutations (WT) will be randomly assigned (1:1:1) to receive a regimen of either gedatolisib, palbociclib, and fulvestrant (Arm A), gedatolisib and fulvestrant (Arm B), or fulvestrant (Arm C). Up to 351 subjects who are PIK3CA WT will be enrolled.

Subjects who meet eligibility criteria and have confirmed PI3KCA mutations (MT) will be randomly assigned (3:3:1) to receive a regimen of either gedatolisib, palbociclib, and fulvestrant (Arm D), alpelisib and fulvestrant (Arm E), or gedatolisib plus fulvestrant (Arm F). Up to 350 subjects who are PIK3CA MT will be enrolled.