CBT Pharmaceuticals has enrolled the first participant in a Phase 1 trial assessing genolimzumab (CBT-501) as a treatment for recurrent or refractory solid tumors.
The study is expected to include 50 patients with selected solid tumors, including mesothelioma, at several centers in Australia. The first patient was dosed at Linear Clinical Research.
“The dosing of our first subject with genolimzumab is a significant milestone for the company, and we are very pleased to begin the development of this important second-generation PD-1 drug candidate intended to treat patients with cancer,” Sanjeev Redkar, PhD, president and chief executive officer of CBT Pharmaceuticals, said in a press release. “In the clinic, we hope to define the unique characteristics of this agent shown pre-clinically, and ultimately, differentiating it in a combination approach with other targeted agents, standard marketed therapies, and other immune-oncology agents.”
Genolimzumab is a humanized antibody that targets the PD-1 protein receptor on immune cells. Preclinical findings indicate it is effective as the approved anti-PD-1 antibodies Opdivo (nivolumab) and Keytruda (pembrolizumab), and is safe.
Its anti-tumor activity, safety and tolerability will be investigated in the CB-501-01 trial (NCT03053466), a Phase 1, multi-center, dose-escalation study.
Those conducting the trial are seeking patients with mesothelioma or other relapsed or recurrent solid tumors, or colorectal, endometrial, gastric, liver, lung, ovarian, or kidney cancer.
The study will be in two parts. In Part 1, patients will be assigned one of three dose levels of genolimzumab, and treated twice a month for four 28-day cycles. Each dose cohort will include three patients.
After a recommended Phase 2 dose is established, genolimzumab’s effectiveness against two or more select tumor types will be evaluated. The main measurements will be the number of patients whose tumor regressed, and the duration of response to the treatment. Progression-free survival will also be evaluated.
“We are very excited to commence dosing on the first-in-human trial of CBT-501, which has been specifically developed with improved characteristics over existing PD-1 inhibitors,” said Professor Michael Millward, lead investigator at Linear Clinical Research. He is also chair of clinical cancer research at the University of Western Australia and head of Medical Oncology at Sir Charles Gairdner Hospital in Perth.