OnCusp Therapeutics, Inc., a clinical stage biopharmaceutical company dedicated to transforming cutting-edge preclinical innovation into clinically validated treatments for cancer patients, today announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track Designation (FTD) to CUSP06, a Cadherin-6 targeting Antibody-Drug Conjugate (CDH6 ADC) and the company’s lead program, for the treatment of patients with platinum-resistant ovarian cancer (PROC).

“We are extremely pleased that the FDA granted Fast Track Designation to CUSP06,” said Eric Slosberg, PhD, Chief Development Officer of OnCusp Therapeutics. “The early results from our Phase 1 trial have been encouraging, and this designation will expedite our efforts to bring this potentially transformative therapy to patients. Given the need for new therapeutic options in this underserved population, we are committed to working closely with the FDA to accelerate its development.”

The ongoing Phase 1 multicenter study is evaluating the safety, tolerability, pharmacokinetics, and preliminary efficacy of CUSP06 in adults with platinum-refractory/resistant ovarian cancer and other advanced solid tumors (CUSP06-1001). Early data from the trial have shown promising anti-tumor activity and a manageable safety profile, supporting further development of the program.

About CUSP06

CUSP06, a CDH6 ADC, is composed of a proprietary antibody with high CDH6 binding affinity, a protease-cleavable linker, and an exatecan payload (a potent and clinically validated topoisomerase-1 inhibitor). The linker is designed to complement the exatecan payload, enabling a stable and homogenous ADC. The payload is a weak substrate for BCRP/P-gp, which are drug efflux pumps that drive chemoresistance to many therapies. In preclinical data, this linker-payload has been shown to have an increased “bystander effect” compared to competitor ADCs. CUSP06 has a drug-to-antibody ratio of eight. OnCusp obtained the exclusive global rights (outside of China) to lead the development and commercialization of CUSP06 from Multitude Therapeutics in 2022. CUSP06 is being evaluated in a Phase 1 study in patients with platinum-refractory/resistant ovarian cancer and other advanced solid tumors. Additional information on the CUSP06-1001 (NCT06234423) trial can be found at clinicaltrials.gov.