Palatin Begins Phase 2 Study of Bremelanotide with PDE5i for Erectile Dysfunction

Palatin Technologies, Inc., based in Cranbury, N.J., is a biopharmaceutical company focusing on pioneering medications that influence the melanocortin receptor system. On June 20, 2024, the company announced the launch of a Phase 2 clinical trial for a new treatment targeting erectile dysfunction (ED) in patients who do not respond to phosphodiesterase 5 inhibitor (PDE5i) monotherapy. The treatment will involve bremelanotide (BMT), a melanocortin 4 receptor (MC4R) agonist, used in conjunction with a PDE5i. Results from this study are anticipated by the end of 2024.

Carl Spana, Ph.D., President and CEO of Palatin, highlighted the significant unmet need in the ED treatment market. He noted that approximately 30-40% of men with ED show minimal to no improvement with PDE5i monotherapies like Viagra, Cialis, and Levitra. Despite these drugs generating over $4 billion in annual sales, their inefficacy in a substantial portion of patients underscores the need for more effective solutions. Spana expressed confidence that combining BMT with PDE5i could offer a synergistic and effective treatment for these non-responders.

The Phase 2 trial will involve around 50 patients and will be conducted as an open-label, dose-escalation study. The goal is to determine the safety and effectiveness of the BMT-PDE5i combination in men who have previously not responded to PDE5i alone. The trial is being carried out under an investigator-sponsored Investigational New Drug (IND) application, with clearance from the Food and Drug Administration (FDA) and approval from an Institutional Review Board (IRB).

Dr. Jed Kaminetsky, the lead investigator for the study, emphasized the growing prevalence of ED, particularly among younger men, and its significant impact on quality of life. Kaminetsky noted that many of his patients are seeking more effective treatments, as those with severe ED often do not respond well to PDE5i monotherapy and have few non-surgical options. He has already observed positive outcomes using bremelanotide in his practice and believes that its combination with a PDE5i could be a promising treatment for those who do not respond to PDE5i alone.

Palatin has previously conducted several clinical studies involving bremelanotide, both as a standalone treatment and in combination with PDE5i, observing statistically significant improvements in erectile function. Additionally, bremelanotide is FDA-approved for the treatment of hypoactive sexual desire disorder (HSDD) in pre-menopausal women, marketed under the brand name Vyleesi. This approval underscores the compound's potential in addressing various sexual health disorders.

Palatin is also developing a new co-formulation of bremelanotide and a PDE5i, intended to be administered as a single injection. An IND for this innovative co-formulation is expected to be submitted to the FDA within the year, with a potential Phase 3 clinical trial for ED patients who do not respond to PDE5i monotherapy projected to commence in the first half of 2025.

Erectile dysfunction affects an estimated 30 million men in the United States, according to the Centers for Disease Control and Prevention (CDC). While PDE5i drugs like sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) are standard treatments, about 30-40% of men do not respond to these therapies, and options for these non-responders are limited.

Palatin Technologies continues to focus on developing first-in-class medications that address significant unmet medical needs. The company's strategy includes forming marketing collaborations with industry leaders to maximize the commercial potential of its products.