CUSP06 put on FDA fast track for platinum-resistant ovarian cancer
Phase 1 trial now testing therapy’s ability to reduce, eliminate tumors
The U.S. Food and Drug Administration (FDA) has granted fast-track status to CUSP06, Oncusp Therapeutics’ treatment candidate for platinum-resistant ovarian cancer.
This designation is given to accelerate the development of investigational therapies with the potential to fill unmet medical needs. FDA fast track status allows a therapy’s developer to have more frequent meetings with regulators throughout the drug development process.
The safety and preliminary efficacy of CUSP06 — Oncusp’s lead program — are now being tested in an ongoing Phase 1 clinical trial (NCT06234423) in the U.S. That trial, slated to run through 2027, is expected to enroll 180 individuals with platinum-resistant ovarian cancer and other advanced solid tumors.
“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,” Eric Slosberg, PhD, Oncusp’s chief development officer, said in a company press release. “We are extremely pleased that the FDA granted fast track designation to CUSP06.”
FDA fast track status aims to speed development of therapies for unmet needs
Ovarian cancer is a type of cancer that originates in the ovaries, the female reproductive organs. The initial treatment for ovarian cancer usually involves platinum-based chemotherapy, which works to stop cancer cells from growing.
However, about 80% of those who respond initially to the treatment will develop platinum resistance. Defined as having disease progression within six months after completing treatment, platinum resistance is typically associated with a poor prognosis, with limited treatment options available.
CUSP06 is an antibody-based therapy designed to target cadherin-6, a protein involved in cell adhesion that’s commonly found at higher levels in ovarian cancer cells. The antibody includes a linker that can be broken down by specific enzymes, allowing the therapy to release its active component — a chemotherapy drug called exatecan, which targets an enzyme involved in cancer cell growth.
In preclinical studies, the therapy specifically targeted and bound to the surface of cancer cells and was effectively taken up by ovarian cancer cells. In laboratory experiments, the treatment inhibited the growth of these cancer cells. Additionally, when tested in animals implanted with ovarian cancer cells from patients, the therapy led to a reduction in tumor size.
Given the need for new therapeutic options in this underserved [patient] population, we are committed to working closely with the FDA to accelerate [CUSP06’s] development.
The Phase 1 trial started dosing patients last year and is primarily assessing the treatment’s safety and tolerability for up to three years. It’s also assessing its preliminary efficacy in reducing tumor size or eliminating tumors completely. Researchers additionally are working to determine the maximum tolerated dose and/or the recommended dose for further trials.
Among the secondary goals for the Phase 1 trial are assessing the treatment’s pharmacological properties and other measures of efficacy, such as time to disease progression and progression-free and overall survival.
According to the company, early data from the trial has shown promising anti-tumor activity and a manageable safety profile, supporting the therapy’s further development.
“Given the need for new therapeutic options in this underserved [patient] population, we are committed to working closely with the FDA to accelerate … development” of CUSP06, Slosberg said.
Oncusp obtained exclusive global rights, outside of China, from Multitude Therapeutics in 2022, for the development and commercialization of CUSP06.
