Lenabasum Fails to Lessen Exacerbations in CF Patients in Phase 2 Trial

A Phase 2 clinical trial of oral lenabasum in people with cystic fibrosis (CF) failed to meet its primary goal of reducing pulmonary exacerbations, the investigational therapy’s developer, Corbus Pharmaceuticals, announced.

“We are very disappointed that the study did not meet the primary endpoint,” Barbara White, MD, chief medical officer and head of research at Corbus, said in a company press release.

Lenabasum — formerly known as anabasum, JBT-101, or resunab — is a synthetic, small molecule designed to reduce inflammation and limit fibrosis by binding to a receptor present on activated immune cells called cannabinoid receptor type 2 (CB2).

Data from a previous Phase 2 clinical trial, CF-001 (NCT02465450), suggested that the treatment lowered the frequency of pulmonary exacerbations, periods when lung function suddenly gets worse. This study, which concluded in 2016, evaluated the treatment against placebo in 85 CF patients.

The recent Phase 2 clinical trial, called CF-002 (NCT03451045), enrolled about 415 CF patients ages 12 and up, at high risk for recurrent pulmonary exacerbations.

The CF-002 study enrolled people at sites in the U.S., Canada, and Europe, and was sponsored by Corbus with the help of the Cystic Fibrosis Foundation (CFF).

Participants were randomly assigned to one of two doses of oral lenabasum — 5 or 20 mg — or a placebo twice a day for 28 weeks. Lenabasum or placebo was given in addition to participants’ background CF treatment.

After completing the trial’s 28 weeks, all enrolled were followed for an additional four weeks.

The study’s primary endpoint — its main measure of efficacy — was the rate of new pulmonary exacerbations. It did not reach this goal, as results showed no statistically significant difference in exacerbation rates between patients treated with lenabasum and those on a placebo.

“We are disappointed with the results of the study,” J.P. Clancy, MD, vice president of clinical research at the CFF, said in a foundation press release.

“We recognize that people with cystic fibrosis need additional treatment options to reduce the frequency of pulmonary exacerbations, and that this is particularly true for individuals who do not yet have a therapy approved for their underlying mutation,” Clancy said. “The CF Foundation remains committed to pursuing new research in inflammation that could lead to new treatments.”

Top-line trial data suggested that lenabasum’s use was generally safe and well-tolerated. Additional study results are being presented at the North American Cystic Fibrosis Conference (NACFC) that takes place virtually this month.

“We look forward to providing more details of study results … at NACFC. We thank the participants, the staff at study sites, the Cystic Fibrosis Foundation, and the European Cystic Fibrosis Society Clinical Trials for their support and partnership throughout this study,” White said.

As a potential CF treatment, lenabasum has been designated an orphan drug by the U.S. Food and Drug Administration (FDA) and by the European Medicines Agency. The FDA also granted the therapy fast track designation; all these designations work to support and advance its development.