Ventrus Biosciences has shelved its Phase III-stage topical drug iferanserin (VEN 309) following disappointing results from a Phase III study in patients with hemorrhoids, which failed to meet its primary and secondary endpoints. The 603-patient study compared treatment with either iferanserin (a selective peripheral 5-HT2A receptor antagonist) or placebo, in terms of elimination of bleeding, and itching and pain. “The outcome of our Phase III study comes as a surprise and a disappointment, particularly given the strong evidence of activity in our Phase II randomized study,” admits Russell H. Ellison, M.D., Ventrus chairman and CEO.
Ventrus says ditching further development of iferanserin will free up enough resources to allow it to complete clinical development and registration of its diltiazem cream candidate VEN 307 in the treatment of anal fissures, and push on with Phase II development of a topical phenylephrine candidate VEN 308 in the treatment of fecal incontinence. The firm licensed exclusive North American rights to VEN 307 for the topical treatment of anal fissures from S.L.A. Pharma, which started a Phase III clinical trial in the EU in November 2010.
“With the planned elimination of all VEN 309-related expenses, we believe the company is sufficiently capitalized to take VEN 307 through a second Phase III study and to approval,” Dr. Ellison adds. “In addition to VEN 307, we look forward to beginning the advancement of our VEN 308 program, as we believe an aging population and increase in gastroenterologic procedures has treated a heightened demand for new and better options in managing fecal incontinence.” In May the firm reported positive data from the first Phase III study evaluating diltiazem in 465 patients with anal fissures. A second Phase III study is expected to start before year end.
Ventrus estimates that there are currently some 4.3 million cases of anal fissures in the U.S., yet no FDA-approved drugs for the treatment of pain associated with the condition. Diltiazem is a well-used hypertension and angina therapy, which gastroenterologists mix or compound on a per-patient basis for topical application to help reduce pain associated with anal fissures.