#United States #Princeton #Ovarian Cancer #OnCusp Therapeutics #CUSP06

OnCusp Therapeutics Showcases Phase 1a Results for CUSP06

On June 2, 2025, at the American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, OnCusp Therapeutics, a company known for its pioneering biopharmaceutical work, presented promising initial results from a Phase 1 study of CUSP06, a CDH6-directed antibody-drug conjugate (ADC). This drug targets patients suffering from platinum-refractory or platinum-resistant ovarian cancer, a challenging condition that often presents limited treatment options. The data presented are particularly encouraging for patients with heavily pretreated high-grade serous ovarian cancer (HGSOC)

Early Results from Phase 1a Study

The Phase 1 trial, an open-label, multicenter, first-in-human study, aims to evaluate the safety, tolerability, pharmacokinetics, and preliminary efficacy of CUSP06. So far, data from 37 patients, who have undergone extensive previous treatments, indicate that the drug maintains a manageable safety profile and offers promising signs of efficacy in this difficult-to-treat cohort. The participants received CUSP06 once every three weeks at doses ranging between 1.6 to 5.6 mg/kg.

Dr. Bing Yuan, Co-Founder and CEO of OnCusp Therapeutics, expressed optimism in the findings. He stated, "The early results, particularly in platinum-resistant HGSOC, demonstrate encouraging activity without necessitating CDH6 biomarker selection, underscoring the potential of CUSP06 as a leading therapeutic."

Among the 25 patients with HGSOC evaluated, an overall response rate (ORR) of 36% was observed, with 9 patients responding positively. In particular, those receiving 4.0 mg/kg and 4.4 mg/kg doses showed response rates of 50%. Furthermore, a remarkable clinical benefit rate (CBR) of 92% was noted, with signs of tumor marker response observed in nearly half of those evaluated.

Safety Profile and Management

The safety data from the Phase 1a study also support continued trials. Most adverse events related to treatment were hematologic, presenting manageable levels of toxicity. These results align with existing data from other topoisomerase-1 inhibitor ADCs, indicating that CUSP06 could become a vital addition to the treatment arsenal against advanced solid tumors.

Future Developments

Looking ahead, OnCusp is moving into Phase 1b of the study where a more detailed analysis of safety and efficacy across select tumor types will be conducted. Moreover, CUSP06 has recently been granted Fast Track designation by the U.S. Food and Drug Administration, marking it as a priority for development concerning platinum-resistant ovarian cancer patients.

Key Components of CUSP06

CUSP06 utilizes a proprietary antibody designed for high CDH6 binding affinity, a protein implicated in the progression of various cancers. The drug's format includes a specialized linker and exatecan payload, targeted for enhanced effectiveness and reduced resistance. This formation aids in circumventing some of the typical challenges associated with chemoresistance seen in traditional therapies.

OnCusp Therapeutics, founded in Princeton, New Jersey, is composed of a dedicated team of experienced pioneers in the biotech sector, aiming to leverage innovative therapies into practical medical solutions. Through their work with CUSP06 and ongoing clinical trials, they hope to revolutionize treatment protocols for difficult oncology cases.

As these promising results unfold, OnCusp is positioned to make impactful contributions to the field of oncology, specifically in enhancing treatment avenues for patients with advanced solid tumors expressing CDH6. The clinical community is keenly awaiting additional data from the ongoing studies, which may establish CUSP06 as a formidable player in solid tumor treatments.

For more details regarding the ongoing clinical trials involving CUSP06, additional resources can be found on ClinicalTrials.gov under trial number NCT06234423.