ARVO 2023: Palatin presents initial dry eye disease phase 3 clinical data

The Melody-1 Phase 3 clinical study is continuing patient enrollment, with final data expected in the second half of 2023. (Image courtesy of Adobe Stock)

Palatin Technologies Inc. today announced the presentation of a poster titled Effectiveness of PL9643 in Treating the Signs and Symptoms of Moderate to Severe Dry Eye Disease: Results From 2 Independent Clinical Trials at the Association of Research in Vision and Ophthalmology (ARVO) Annual Conference.

According to the company, the authors of the poster are George W. Ousler, MS, Robert Jordan, and Carl Spana, PhD. Ousler is an employee of Ora Inc. and Jordan and Spana are employees of Palatin Technologies. The poster was presented by Ousler on Wednesday at the ARVO conference in New Orleans.

"The presented data supports our excitement about PL9643 ocular tolerability and broad efficacy and the potential for PL9643 to become a leading treatment for the many patients that deal with DED," said Spana, president and CEO of Palatin. “The excellent ocular tolerability and efficacy across multiple signs and symptoms of DED distinguishes PL9643 from currently approved treatments for DED."

The goal of the data analysis of the MELODY-1 Lead In patients was to confirm the optimal endpoints, hierarchy of the endpoints and number of patients for the final Phase 3 data analysis. The data analyses showed statistical significance for multiple sign and symptom endpoints. The currently planned sample size for MELODY-1 was selected to provide the optimal opportunity for PL9643 to demonstrate statistical significance for multiple sign and symptom endpoints. The PL9643 MELODY-1 Phase 3 study is expected to have topline data in the second half of 2023.

According to the company, data from a completed Phase 2 clinical trial and from the Lead In population of the ongoing Phase 3 MELODY-1 trial. The data analyses show PL9643 demonstrated effectiveness across multiple clinical signs and reduced symptomatic ocular pain indicating that PL9643 is having a positive affect across multiple regions of the eye, offering a potentially differentiating efficacy profile from currently available treatments for DED. The magnitude of the absolute difference between PL9643 and vehicle exceeds what has been reported for other approved products for several clinical sign and symptom endpoints.

Moreover, presenters noted the safety results from the Phase 2 and initial Phase 3 analysis show that there are no ocular adverse events related to the use of PL9643 and no patients discontinued use of PL9643 because of tolerability issues.

"Based on the safety, ocular tolerability, and efficacy results from the clinical studies, PL9643 may fill an important unmet need in patients with DED," said Michael Raizman, MD, practicing ophthalmologist and CMO of Palatin. "PL9643's novel mechanism of action potentially protects the ocular surface from the damaging effects of inflammation and helps resolve ongoing inflammation."

The melanocortin receptor ("MCr") system has effects on inflammation, immune system responses, metabolism, food intake, and sexual function. There are five melanocortin receptors, MC1r through MC5r. Modulation of these receptors, through use of receptor-specific agonists, which activate receptor function, or receptor-specific antagonists, which block receptor function, can have medically significant pharmacological effects. Many tissues and immune cells located throughout the body, including the gut, kidney and eye, express melanocortin receptors, empowering our opportunity to directly activate natural pathways to resolve disease inflammation.

Drugs based on melanocortin agonists have been approved by the FDA for treating several conditions, including female sexual dysfunction, inflammatory/autoimmune diseases, and rare forms of genetic obesity and.