Corbus Pharmaceuticals Holdings, Inc. announced that it has reached agreement with the U.S. Food and Drug Administration ("FDA") regarding the design of its next study of lenabasum (formerly known as anabasum), a novel, oral, pro-resolving drug, in the treatment of cystic fibrosis ("CF"). The Company and the FDA agreed that the event rate of pulmonary exacerbation is an acceptable sole primary efficacy endpoint for the clinical development program to support registration of lenabasum for the treatment of CF. Event rate of pulmonary exacerbation is the average number of pulmonary exacerbations per subject per time period. The FDA also agreed to the inclusion of adolescents 12-17 years of age alongside adults in the Phase 2b study. The Company expects the first patient to be dosed during this quarter. The Phase 2b multicenter, double-blinded, randomized, placebo-controlled study will enroll approximately 415 subjects with CF who are at least 12 years of age and at increased risk for pulmonary exacerbations. Secondary efficacy outcomes include other measures of pulmonary exacerbations, change in Cystic Fibrosis Questionnaire-Revised Respiratory domain score and change in forced expiratory volume in 1 second (FEV1), % predicted. The study will be conducted in approximately 100 sites across North America, Europe, Israel and Australia. Subjects will be centrally randomized to one of three cohorts to receive lenabasum 20 mg twice per day, lenabasum 5 mg twice per day, or placebo twice per day for 28 weeks, with 4 weeks follow-up off active treatment. This Phase 2b CF study was designed with input from the Therapeutic Development Network of the Cystic Fibrosis Foundation and the European Cystic Fibrosis Society Clinical Trials Network.