Corbus Pharmaceuticals has received approval from the US Food and Drug Administration (FDA) for initiating a 12-month open-label extension study of the in-progress Phase 2 clinical trial of Resunab to treat diffuse cutaneous systemic sclerosis (scleroderma).
Systemic sclerosis is a chronic, systemic autoimmune rheumatic disease with a vague etiology and affects around 35,000-70,000 people in the US, with disease onset typically in midlife.
Nearly 80% of systemic sclerosis patients are women and there are currently no FDA-approved treatments specifically available for the disease.
The proposed open label extension study of Corbus aims to provide all subjects with the option of receiving Resunab after completion of the 84-day treatment period in the ongoing double-blind placebo-controlled study and to gather long term safety and efficacy data on Resunab.
During the study, all subjects, including those who received placebo in the current 84-day, double-blind placebo controlled trial, will receive Resunab.
Clinical endpoints used in the double-blinded placebo-controlled portion of the trial will be observed during the 12-month extension study.
Resunab is a synthetic oral endocannabinoid-mimetic drug that binds to the CB2 receptor expressed on activated immune cells and fibroblasts. It was granted FDA Orphan Drug Designation and Fast Track status for the treatment of systemic sclerosis last year.
Corbus began its Phase 2 clinical trial of Resunab for treatment of systemic sclerosis in August last year.
The multi-centre, double-blind, randomised, placebo-control Phase 2 trial is taking place in the US and is designed to assess Resunab's safety and tolerability in up to 36 individuals with systemic sclerosis.
In addition, the impact on clinical outcomes is measured using the combined response index for diffuse cutaneous systemic sclerosis (CRISS) that involves both patient and physician-reported outcomes.
Subjects in the Phase 2 study are treated for 84 days with a follow-up period of 28 days.
The study also assesses several secondary endpoints, such as Resunab's mechanism of action and effect on biomarkers in systemic sclerosis.
Corbus expects to report top-line results from this study in the last quarter of this year.