Corbus unveils mid-stage study data for investigational cystic fibrosis drug anabasum

Corbus Pharmaceuticals on Thursday said that anabasum achieved the primary endpoint of a Phase II study in patients with cystic fibrosis, with the experimental drug displaying an acceptable safety and tolerability profile at all examined doses with no serious or severe adverse events. CEO Yuval Cohen remarked "we are delighted that in this first-in-CF patient study, anabasum demonstrated an acceptable safety profile and potential clinical benefit in reducing acute pulmonary exacerbations...and that these findings are supported by biomarker data consistently showing reduction of inflammation in the lungs." 

In the study, 85 adults with cystic fibrosis and baseline forced expiratory volume in 1 second (FEV1) predicted of at least 40 percent who were on stable standard-of-care treatment, including Vertex Pharmaceuticals' Orkambi (lumacaftor/ivacaftor), were randomised to treatment with anabasum at a daily dose of 1mg or 5mg, or placebo, for four weeks. Subsequently, anabasum-treated patients were randomly assigned to once- or twice-daily treatment with the drug at a dose of 20mg for eight weeks, with select patients from the placebo arm also randomly assigned to the two groups. 

Top-line results illustrated that anabasum was not associated with improvements in FEV1 percent predicted or changes in Cystic Fibrosis Questionnaire-Revised Respiratory Symptoms Score from baseline versus placebo for either once- or twice-daily treatment after 12 weeks. Meanwhile, Corbus noted that anabasum dosed at 20mg twice daily was associated with a 75-percent decline in the number of acute pulmonary exacerbations defined as those requiring intravenous antibiotics compared to placebo. Specifically, Corbus noted that three patients in the placebo group suffered an acute pulmonary exacerbation, versus one patient dosed with anabasum 20mg twice daily and three patients in the group given the drug on a once-daily basis. In addition, the therapy was also linked to reductions in inflammatory cell counts in sputum. 

Corbus indicated that it plans to hold discussions with experts and various groups regarding the study results and its next steps. The drugmaker then plans to meet with relevant regulatory authorities. 

Anabasum, also known as resunab, was awarded orphan drug and fast track designation by the FDA in 2015 and granted orphan drug status by the European Medicines Agency the following year. The company noted that the therapy is a synthetic oral endocannabinoid-mimetic drug that preferentially binds to the CB2 receptor expressed on activated immune cells and fibroblasts.