King Pharmaceuticals Delays Program With Bremelanotide For Erectile Dysfunction

Palatin Technologies and King Pharmaceuticals have delayed plans for the initiation of Phase 3 clinical trials with bremelanotide, a first in class melanocortin agonist drug candidate, for the treatment of male erectile dysfunction (ED).

The decision follows responses from representatives of the U.S. Food and Drug Administration (FDA), which raised serious concerns about the acceptable benefit/risk ratio to support the progression of the proposed program into Phase 3 studies for ED.

After reviewing the data generated in the Phase 1 and 2 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 3 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, Ph.D., President and Chief Executive Officer of Palatin.

Palatin and King 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.

ED is defined as the consistent inability to attain and maintain an erection sufficient for sexual intercourse. The condition is correlated with increasing age, cardiovascular disease, hypertension, diabetes, hyperlipidemia, and smoking. In addition, certain prescription drugs and psychogenic issues may contribute to ED. It is estimated that some degree of ED affects one half of all men over the age of 40 and that 150 million men worldwide suffer from ED.