Corbus Fully Enrolls Phase 2 Study of Resunab as Treatment for Cystic Fibrosis

Corbus Pharmaceuticals Holdings recently announced the completion of patient enrollment in its Phase 2 clinical trial assessing Resunab for the treatment of cystic fibrosis (CF).

Resunab is a first-in-class, synthetic oral endocannabinoid-mimetic drug that binds to the CB2 receptor present on activated immune cells and fibroblasts, helping resolve inflammation and halting fibrosis. Phase 1 studies have shown Resunab to be safe, well-tolerated by patients and with a favorable pharmacokinetic profile.

The drug also demonstrated promising potency in preclinical studies, essentially triggering systematic pathways to turn off chronic inflammation and fibrotic processes, and without evidence of immunosuppression.

“Resunab’s intended pharmacological activity is resolution of chronically activated innate immune responses including tissue inflammation and fibrosis. This novel mechanism of action is expected to reduce airway obstruction and, ultimately, lung destruction over time in CF,” Barbara White, MD, Corbus’ chief medical officer, said in a press release.

Investigators in this double-blind, randomized, and placebo-controlled trial (NCT02465450) are evaluating the safety, tolerability and efficacy of Resunab in adults with CF, regardless of the patient’s underlying genetic mutation or infecting pathogen.

About 79 patients, at sites across the U.S. and Europe, will receive oral Resunab daily for 84 days, with an additional 28 days of follow-up. Efficacy outcomes include measuring lung function by forced expiratory volume in one second (FEV1) and patient-reported symptoms. In addition, the trial will evaluate Resunab’s impact on sputum microbiota, and biomarkers of inflammation in sputum and blood.

“Inflammation causes lung damage in CF, and none of the approved treatments for CF directly address this aspect of the disease. By activating the resolution phase of inflammation, Resunab has the potential to provide a clinical benefit not being offered by the current medications for CF,” said James Chmiel, MD, MPH, principal investigator for the trial in the U.S., and a professor of pediatrics at Case Western Reserve University.

Resunab was named an orphan drug and given fast track status as a potential CF treatment by the U.S. Food and Drug Administration (FDA) in 2015. In April of that year, Corbus received a $5 million development award from the Cystic Fibrosis Foundation (CFF) to support its Phase 2 trial. The company expects to report top-line results in early 2017.

“We are pleased to have achieved this important clinical milestone for Resunab and will complete this trial before year’s end, with top-line data readout expected early in the first quarter of 2017. We are grateful to the individuals and physicians who have participated in the study and to the Cystic Fibrosis Foundation for its support,” said Yuval Cohen, PhD, Corbus’ chief executive officer.

In addition to CF, Resunab is also being evaluated as a treatment for diffuse cutaneous systemic sclerosis (scleroderma), dermatomyositis, and systemic lupus erythematosus (SLE). In each of these four disease, inflammation results in disease progression.