Dr Meric-Bernstam on the Investigation of CBX-12 in Advanced or Metastatic Solid Tumors

Funda Meric-Bernstam, MD, chair, the Department of Investigational Cancer Therapeutics–the Phase I Program, medical director, the Institute for Personalized Cancer Therapy (IPCT), the Nellie B. Connally Chair in Breast Cancer, the University of Texas MD Anderson Cancer Center, discusses a first-in-human phase 1/2 study (NCT04902872) of CBX-12 in patients with advanced or metastatic solid tumors.

At the 2023 ASCO Annual Meeting, investigators presented data from the study evaluating the peptide drug conjugate, revealing that the maximum tolerated dose for the agent was found to be 45 mg/m2 for 3 days in a 21-day cycle or 60mg/m2 weekly. Myelosuppression was found to be the primary dose-limiting toxicity (DLT), although DLTs of febrile neutropenia and sepsis were both reported twice.

Notably, 5 patients experienced durable objective response or near objective responses per RECIST v1.1 criteria.

Notable any-grade adverse effects (AEs) included anemia (51.1%), fatigue (40.0%), and neutropenia (40.0%), which was not surprising based on the expected toxicity profile for this class of drugs, Meric-Bernstam says. Other any-grade AEs reported in more than 10% of patients included leukopenia, nausea, diarrhea, thrombocytopenia, vomiting, dehydration, and increased alanine transaminase.

The final recommended dosing schedule for CBX-12 in future studies has yet to be determined, Meric-Bernstam continues. However, investigators have been encouraged by the preliminary signs of efficacy displayed with the agent in this heavily pretreated patient population, Meric-Bernstam concludes.