A phase 2b trial of InDex Pharmaceuticals’ ulcerative colitis drug has met its primary endpoint. The trial linked use of the highest dose of the topical TLR9 agonist to a 15% improvement in the clinical remission rate over placebo.
InDex enrolled 213 patients with left-sided moderate to severe active ulcerative colitis in the trial. To participate in the dose optimization trial, patients had to have tried oral 5-ASA medications, glucocorticosteroids and either immunomodulators or TNF-alpha inhibitors such as Johnson & Johnson’s Remicade without success.
In this refractory population, 21.4% of patients who received two 250 mg doses of cobitolimod via topical rectal administration were in clinical remission six weeks after starting treatment. The rate in the placebo cohort was 6.8%, resulting in the trial hitting its primary endpoint with a p value that came in just under the 0.05 threshold.
Lower doses of cobitolimod were less effective, achieving clinical remission rates ranging from 4.7% to 12.5%, but the results nonetheless emboldened InDex to talk up the prospects of the drug ahead of further studies.
“With an outstanding combination of efficacy and safety, cobitolimod is set to take a leading position within the field. We will now advance cobitolimod towards phase 3 and in parallel evaluate the best route to commercialisation,” InDex CEO Peter Zerhouni said in a statement.
InDex first took cobitolimod, then known as Kappaproct, into phase 3 late in 2011. Almirall licensed the European rights to the drug in a deal potentially worth more than €100 million ($111 million) in 2014, only to terminate the agreement a little more than one year later.
The termination followed the delivery of data from the phase 3 trial that began in 2011. The study missed its primary endpoint of clinical remission at 12 weeks but delivered enough encouraging signs against secondary endpoints for InDex to run another trial. Positives included the higher rate of symptomatic remission seen in the treatment group in the fourth week of the study.