Corbus Completes Phase 2 Trial of Potential Scleroderma Therapy Resunab

Corbus Pharmaceuticals recently completed its Phase 2 clinical study (NCT02465437) evaluating the drug Resunab (JBT-101) for the treatment of diffuse cutaneous systemic sclerosis. The company expects to report results from this study later this year.

Resunab is a novel synthetic oral drug that mimics the body’s own cannabinoids (endocannabinoids); the drug selectively binds to the cannabinoid receptor type 2 (CB2). In humans, the endocannabinoid system (ECS) is widespread and maintains balance in the central and peripheral nervous system.

Cannabinoid compounds bind to two kinds of cannabinoid (CB) receptors. The CB1 receptor is mainly found in the brain and spine, regulating the levels of different communication compounds (transmitter substances) of neurons;.

CB1 receptors are responsible for the psychological high people experience from the cannabis plant. The CB2 receptor is mostly found on activated immune cells and fibroblasts in the body, and to a smaller extent, inside the brain. When Resunab binds to the CB2 receptor, it triggers mechanisms that resolve inflammation and halt fibrosis.

The placebo-controlled Phase 2 study focused on evaluating the safety and effectiveness of Resunab, and was conducted at nine centers in the U.S. In total, 42 patients with systemic sclerosis were treated with Resunab for 85 days and evaluated for an additional 28-day follow-up period without treatment.

Disease-related improvements were measured with the Composite Response Index for diffuse cutaneous Systemic Sclerosis (CRISS), which calculates changes in five domains. Changes in other patient-reported outcomes, and biomarkers of inflammation and fibrosis in systemic sclerosis, were also evaluated.

“We are grateful to all the individuals and clinicians who participated in this study and look forward to announcing top-line data as it becomes available this quarter,” Corbus CEO Yuval Cohen, PhD, said in a press release.

In April 2016, Corbus received approval from the U.S. Food and Drug Administration (FDA) for an open-label extension of the Phase 2 clinical trial, which allowed all participants in the study to receive Resunab for an additional 12 months.

According to the profile of Resunab, apart from systemic sclerosis, the drug may also be useful in several other conditions in which inflammation contributes to disease progression. In fact, Resunab is currently being evaluated in Phase 2 clinical trials for the treatment of cystic fibrosis, dermatomyositis, and systemic lupus erythematosus. The drug has been shown to be a safe and potent anti-inflammatory agent in previous preclinical and Phase 1 clinical studies.