Corbus Pharmaceuticals Begins Dosing in Phase 1 Study of CB1 Inverse Agonist CRB-913 for Obesity

NORWOOD, MA, USA I March 28, 2025 I Corbus Pharmaceuticals Holdings, Inc. (NASDAQ: CRBP), a company specializing in oncology and obesity treatments, has announced the initiation of the dosing phase for the first participant in their Phase 1 trial of CRB-913. This trial, which involves both single ascending dose (SAD) and multiple ascending dose (MAD) evaluations, aims to assess the drug's efficacy in combating obesity. The study is being carried out in the United States and operates under an open Investigational New Drug (IND) application.

CRB-913 is a cutting-edge drug that acts as a highly peripherally restricted CB1 receptor inverse agonist, developed specifically to address obesity. The mechanism of CB1 inverse agonism has been previously validated in clinical settings as effective for weight loss. However, earlier drugs in this category, such as rimonabant, were discontinued due to potential neuropsychiatric side effects. The current focus is on developing second-generation peripherally restricted CB1 inverse agonists, including CRB-913 and monlunabant, to mitigate these risks.

At the Obesity Week 2024 conference, pre-clinical data revealed that CRB-913 exhibits significantly higher peripheral restriction compared to both monlunabant and rimonabant. Specifically, in non-clinical models, CRB-913 demonstrated a brain-to-plasma ratio fifty times lower than rimonabant, and it is fifteen times more peripherally restricted than monlunabant.

The SAD/MAD phase of the Phase 1 trial is anticipated to conclude by the third quarter of this year. Following this, Corbus plans to initiate a Phase 1b dose-range finding study in the latter part of 2025, with completion expected in the second half of 2026.

Yuval Cohen, Ph.D., the Chief Executive Officer of Corbus, expressed enthusiasm about this significant advancement in the CRB-913 obesity program. He highlighted the potential for this new treatment to meet several unmet needs in weight loss management, particularly through its novel mechanism of action and oral administration as a small molecule. Dr. Cohen also noted the promising pre-clinical data, suggesting CRB-913 could be effective as both a standalone therapy and in combination with incretin analogs, as well as a maintenance therapy following initial incretin analog treatment.

Corbus Pharmaceuticals, headquartered in Norwood, Massachusetts, is committed to advancing the treatment of serious illnesses through innovative scientific methods. Their diversified pipeline includes CRB-701, a next-generation antibody drug conjugate targeting Nectin-4 on cancer cells to deliver a cytotoxic payload, and CRB-601, an anti-integrin monoclonal antibody designed to inhibit TGFβ activation on cancer cells, in addition to CRB-913 for obesity treatment.