King and Palatin delay Ph III for bremelanotide

Palatin Technologies and fellow USA-based King Pharmaceuticals have delayed plans for the initiation of Phase III clinical trials with bremelanotide, a first-in-class melanocortin agonist drug candidate, for the treatment of male erectile dysfunction. The decision follows responses from representatives of the Food and Drug Administration, which raised serious concerns about the acceptable benefit/risk ratio to support the progression of the proposed program into Phase III studies for ED, the companies noted.

After reviewing the data generated in the Phase I and II studies, the FDA questioned the overall efficacy results and the clinical benefit of this product in both the general and diabetic ED populations, and cited blood pressure increases as its greatest safety concern. Though not supportive of the proposed Phase III studies for ED with bremelanotide, the FDA stated that it was amenable to proposals for a different drug development pathway, such as for a second-line therapy in non-responders to currently approved PDE-5 inhibitors.

"The safety of patients in our clinical program has always been our number one priority and we will work closely with the FDA, King and our advisors to determine the next steps for the program," stated Carl Spana, chief executive of Palatin. The two firms plan to review the FDA comments in the overall context of the program in order to determine next steps related to the further development of bremelanotide for the treatment of ED.