Palatin Technologies completes Phase 2 obesity trial with MC4R bremelanotide and GLP-1/GIP tirzepatide

Palatin Technologies, Inc. has announced the completion of its Phase 2 BMT-801 clinical trial, a study evaluating the co-administration of MC4R bremelanotide with GLP-1/GIP tirzepatide for the treatment of obesity. The final patient enrolled in the trial has completed their last visit, marking a key milestone for the biopharmaceutical company. Topline data from the study are expected later this quarter, which could provide critical insights into the effectiveness of this combination therapy in addressing the global obesity epidemic.

What is the significance of Palatin’s Phase 2 obesity trial?

The completion of the Phase 2 BMT-801 trial represents an important step in Palatin Technologies’ efforts to develop innovative treatments for obesity. The trial, formally titled “BMT-801, A Phase II, Randomized, Double-Blind, Placebo-Controlled Study Investigating the Safety, Tolerability, and Effectiveness of Co-Administration of Bremelanotide with Tirzepatide for the Treatment of Obesity,” enrolled 113 patients across four U.S.-based clinical sites. This figure nearly doubles the initial target of 60 participants, driven by strong patient demand and streamlined trial operations.

The study aims to evaluate the safety and efficacy of co-administering MC4R bremelanotide with GLP-1/GIP tirzepatide—two compounds that target different mechanisms in the body’s weight regulation system. According to Palatin Technologies, this combination has the potential to deliver additive and synergistic effects on weight loss, addressing gaps in existing obesity treatments that often rely on single-mechanism approaches.

How does the MC4R pathway influence obesity treatment?

At the heart of this clinical trial is the melanocortin 4 receptor (MC4R), a key player in regulating appetite and energy expenditure. Located in the paraventricular nucleus of the hypothalamus, the MC4R pathway controls how the brain responds to hunger and satiety signals. Genetic mutations affecting MC4R signalling can lead to hyperphagia, decreased energy use, and early-onset obesity, particularly in individuals with rare genetic obesity disorders.

While natural substances like agouti-related peptide and neuropeptide Y stimulate appetite by antagonising MC4R, MC4R agonists such as bremelanotide promote feelings of fullness (satiety), helping to reduce food intake. This mechanism makes MC4R an attractive target for new obesity treatments, especially when combined with drugs like tirzepatide, which modulate the GLP-1 and GIP receptors involved in glucose metabolism and appetite control.

What sets Palatin’s obesity treatment apart from existing therapies?

The combination of MC4R bremelanotide with GLP-1/GIP tirzepatide represents a novel approach to obesity treatment, as it targets multiple biological pathways simultaneously. Current anti-obesity medications, such as GLP-1 receptor agonists, have shown promising results in weight reduction, but many patients experience plateaus in weight loss or face challenges maintaining results over the long term.

Carl Spana, Ph.D., President and Chief Executive Officer of Palatin Technologies, highlighted the potential benefits of this multi-target strategy. He stated that the combination therapy could offer enhanced weight loss outcomes compared to existing treatments, as well as address unmet needs in conditions like acquired and congenital hypothalamic obesity and rare genetic disorders linked to MC4R pathway dysfunction.

“The MC4R pathway plays a pivotal role in eating behaviour and how the body manages energy,” Dr. Spana explained. “We believe that MC4R agonists, particularly our long-acting peptides and oral small molecule agonists, will be critical in treating obesity, whether used alone or in combination with other therapies like GLP-1/GIP drugs.”

What are the primary goals of the Phase 2 BMT-801 trial?

The primary endpoint of the Phase 2 BMT-801 trial is to assess the impact of the combined therapy on body weight reduction, alongside evaluating safety and tolerability. Participants were initially treated with tirzepatide alone for four weeks to confirm eligibility, after which they were randomised into one of four treatment regimens, including placebo-controlled groups.

Throughout the trial, researchers conducted multiple assessments to monitor changes in body weight, metabolic health markers, and potential side effects. These data will help determine whether bremelanotide can be effective as a standalone treatment for obesity or if it works best in conjunction with GLP-1/GIP therapy.

What’s next for Palatin Technologies in obesity research?

With the completion of patient visits, Palatin Technologies is now focused on final data collection and quality control processes. Topline results from the trial are expected later this quarter, which will provide key insights into the potential of the combination therapy to advance into Phase 3 trials.

Dr. Spana emphasised that the findings from BMT-801 will inform the company’s broader clinical development programmes, including potential applications for both general obesity management and rare, genetically driven obesity disorders. The results could also have implications for the company’s pipeline of MC4R-targeting therapies, positioning Palatin Technologies as a leader in the evolving obesity treatment landscape.

Why does this study matter in the fight against obesity?

Obesity remains a global health crisis, with rates continuing to rise despite the availability of multiple pharmacological and lifestyle interventions. The need for more effective, sustainable treatments is critical, especially for patients who do not respond adequately to current therapies. By exploring new mechanisms of action through the MC4R pathway and combining them with established GLP-1/GIP therapies, Palatin Technologies aims to fill this treatment gap.

As anticipation builds for the upcoming trial data, the scientific and medical communities are watching closely to see whether this combination therapy could represent a breakthrough in obesity management.