Celcuity Inc. (NASDAQ:CELC), a clinical-stage biotechnology company focused on the development of targeted therapies for the treatment of multiple solid tumor indications, today announced updates to the Phase 3 VIKTORIA-2 clinical trial of gedatolisib as a first-line treatment for patients with hormone receptor positive ("HR+"), human epidermal growth factor receptor 2 negative ("HER2-") locally advanced or metastatic breast cancer ("ABC").

Following last year's announcement and subsequent data presentation demonstrating clinically meaningful improvement in progression-free survival ("PFS") for patients treated with gedatolisib combined with palbociclib and fulvestrant compared to those treated with fulvestrant in the PIK3CA wild-type ("WT") cohort of the VIKTORIA-1 Phase 3 study, several important elements of the VIKTORIA-2 clinical trial protocol have been amended. First, in addition to evaluating patients in the first-line setting with endocrine-resistant HR+/HER2- ABC, VIKTORIA-2 will now include a separate study to evaluate the safety and efficacy of patients in the first-line setting who have endocrine-sensitive HR+/HER2- ABC. Second, patients will be assigned manually according to their endocrine sensitivity status to either Study 1 (endocrine-resistant) or Study 2 (endocrine-sensitive) and subsequently be randomized to a treatment arm. Third, efficacy analyses for both Study 1 and Study 2 of VIKTORIA-2 will evaluate the entire intent-to-treat population (combined WT and mutant type ("MT")) enrolled in their respective study. Each study will have independent statistical analysis plans that will include separate primary endpoints. The primary endpoints for the VIKTORIA-2 clinical trial are PFS, per RECIST 1.1 criteria, as assessed by blinded independent central review ("BICR").

Prior to finalizing the amended Phase 3 trial design, Celcuity conducted a Type B meeting with the U.S. Food and Drug Administration (the "FDA") to obtain their feedback and to gain alignment on these planned amendments.

"We are excited to expand the VIKTORIA-2 study to include patients with endocrine-sensitive HR+/HER2- ABC. For patients with endocrine-sensitive HR+/HER2- advanced breast cancer who received gedatolisib in combination with palbociclib and letrozole in our Phase 1b clinical trial, median progression free survival was 48.6 months, median overall survival was 77.3 months, and the objective response rate was 79%," said Igor Gorbatchevsky, MD, Chief Medical Officer of Celcuity. "These results are very encouraging and compare favorably to published data for the current standard-of-care regimens for these patients."

"Results from the PIK3CA wild-type and mutation cohort of our VIKTORIA-1 study demonstrated the benefit of gedatolisib combination treatment in HR+/HER2- ABC in the second-line setting," said Brian Sullivan, CEO and co-founder of Celcuity. "Developing the gedatolisib triplet for nearly all patients in the first-line setting, irrespective of their endocrine sensitivity or PIK3CA status, offers the potential to advance the standard of care for the approximately 90,000 women each year who are diagnosed with late-stage HR+/HER2- ABC."

Gedatolisib Subcutaneous Formulation

 

To support its long-term lifecycle development plan, Celcuity also announced that it submitted to the United States Patent and Trademark Office ("USPTO") its first patent application for a subcutaneous formulation of gedatolisib that would enable a patient to receive gedatolisib as an injection as an alternative to an infusion. Development of the subcutaneous gedatolisib formulation is ongoing with the goal of demonstrating clinical equivalence to the current intravenous formulation of gedatolisib. The subcutaneous formulation is aimed to support potential future indications for gedatolisib regimens that may result in duration of treatment periods greater than several years.

"As we initiate pivotal studies for indications that may offer several years of progression-free survival benefit, development of a subcutaneous formulation of gedatolisib would particularly benefit patients who may potentially be receiving treatment with gedatolisib for extended time periods," said Brian Sullivan, CEO and co-founder of Celcuity.