Pre-Clinical Data of Palatin’s Melanocortin Agonist Demonstrating Therapeutic Effects in Diabetic Retinopathy and Uveitis Published in the International Journal of Molecular Sciences

 Apr 18, 2023, 07:30 ET 

–  International Journal of Molecular Sciences manuscript demonstrates robust pre-clinical data in two retinal disease models

–  Studies further demonstrate broad utility of melanocortin agonists in treating inflammatory conditions, especially in the eye

CRANBURY, N.J., April 18, 2023 /PRNewswire/ — Palatin Technologies, Inc. (NYSE American: PTN), a biopharmaceutical company developing first-in-class medicines based on molecules that modulate the activity of the melanocortin receptor system, today announced The International Journal of Molecular Sciences published a manuscript, “Stimulating the Melanocortin System in Uveitis and Diabetes Preserves the Structure and Anti-Inflammatory Activity of the Retina” by Tat Fong Ng and Andrew W. Taylor from Department of Ophthalmology, Boston University Chobanian and Avedisian School of Medicine, in Boston, Massachusetts. The manuscript summarizes data demonstrating the effects of PL8331 in two mouse models of retinal disease, experimental autoimmune uveoretinitis (EAU) and diabetic retinopathy (DR). Palatin and the National Institute of Health (NIH) and the Massachusetts Lions Eye Research Foundation provided funding for the study.

“We have long studied the endogenous mechanisms of anti-inflammatory activity within the healthy eye, in which the melanocortin system is key,” stated Andrew W. Taylor, Ph.D., Associate Dean of Research at Boston University. “Our results show that engaging the melanocortin system in eye pathology is more than suppressing inflammation. It promotes cell survival and preserves normal anti-inflammatory activity within the eye.”

Both models evaluated the efficacy of PL8331 as an agonist at the melanocortin 1 (MC1r) and melanocortin 5 (MC5r) receptors.

In the EAU mouse model, PL8331 treatment resulted in resolution of inflammation and preservation of retinal structure. Specifically, PL8331 protected the retinal photoreceptors from the auto-inflammatory damage that normally occurs in the EAU model.

In the DR mouse model, PL8331 treatment resulted in enhanced survival of various types of retinal cells and the suppression of vascular endothelial growth factor (VEGF). VEGF plays a major role in the pathology of DR. In addition, the retinal pigmented epithelial cells (RPE) were able to maintain their normal anti-inflammatory activity.

“This manuscript summarizes quite nicely the great potential of utilizing melanocortin agonists to treat inflammatory conditions in the back of the eye, specifically the retina,” said Carl Spana, Ph.D., President and CEO of Palatin. “This data adds to Palatin’s extensive pre-clinical data with melanocortin agonist in retinal disease models and supports future clinical development.”

The findings from both studies clearly demonstrate the importance of the melanocortin system in protecting the eye from the damage caused by pathological inflammation and support the potential of melanocortin agonists as treatments for various retinal diseases.

About Uveitis

Non-infectious uveitis is a group of inflammatory diseases not due to an active infection that produces swelling and destroys eye tissue. The disease is caused by inflammatory responses inside the eye, which may be initiated by autoimmune responses, responses to infections or tumors within the eye or other parts of the body, physical injury or toxins. Uveitis is classified by where it occurs in the eye, including intermediate, posterior, pan uveitis and chronic anterior uveitis. Uveitis can be associated with several diseases, including autoimmune diseases. Initial non-infectious uveitis symptoms include blurred vision, eye pain, dark floating spots in vision and light sensitivity. Uveitis can cause vision loss or blindness if left untreated.

About Diabetic Retinopathy

Diabetic retinopathy, also known as diabetic eye disease, is a medical condition in which damage occurs to the blood vessels of the retina (light-sensitive tissue at the back of the eye) due to diabetes mellitus. It is a leading cause of blindness in people aged 20 to 64 and affects up to 80 percent of those who have had diabetes for 20 years or more and a major cost to the nation’s healthcare system.

According to the Diabetic Retinopathy Clinical Research Network (, the number of people in the US affected by diabetic retinopathy will reach 11.3M by 2030 and 14.6M by 2050, and 28 million with vision-threatening DR (VTDR) worldwide. The CDC estimates that the prevalence of DR will triple from 2005 (5.5M) to 2050 (16M).

About Melanocortin Receptor Agonists and 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 inflammatory/autoimmune diseases, rare forms of genetic obesity and female sexual dysfunction.

About Palatin

Palatin is a biopharmaceutical company developing first-in-class medicines based on molecules that modulate the activity of the melanocortin receptor systems, with targeted, receptor-specific product candidates for the treatment of diseases with significant unmet medical need and commercial potential. Palatin’s strategy is to develop products and then form marketing collaborations with industry leaders to maximize their commercial potential. For additional information regarding Palatin, please visit Palatin’s website at and follow Palatin on Twitter at @PalatinTech.

Forward-looking Statements

Statements in this press release that are not historical facts, including statements about future expectations of Palatin, such as statements about PL8331 preclinical results in  two mouse models of retinal disease, experimental autoimmune uveoretinitis and diabetic retinopathy, and potential utility in treating humans, are “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934 and as that term is defined in the Private Securities Litigation Reform Act of 1995. Palatin intends that such forward-looking statements be subject to the safe harbors created thereby. Such forward-looking statements involve known and unknown risks, uncertainties and other factors that could cause Palatin’s actual results to be materially different from its historical results or from any results expressed or implied by such forward-looking statements. Palatin’s actual results may differ materially from those discussed in the forward-looking statements for reasons including, but not limited to, results of clinical trials, regulatory actions by the FDA and other regulatory and the need for regulatory approvals, Palatin’s ability to fund development of its technology and establish and successfully complete clinical trials, the length of time and cost required to complete clinical trials and submit applications for regulatory approvals, products developed by competing pharmaceutical, biopharmaceutical and biotechnology companies, commercial acceptance of Palatin’s products, and other factors discussed in Palatin’s periodic filings with the Securities and Exchange Commission. Palatin is not responsible for updating for events that occur after the date of this press release.

Palatin Technologies® is a registered trademark of Palatin Technologies, Inc.

SOURCE Palatin Technologies, Inc.

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