Palatin Technologies, Inc. Reports Positive Bremelanotide Study; Improved Safety Profile With Subcutaneous Administration

Main Category: Erectile Dysfunction / Premature Ejaculation
Also Included In: Sexual Health / STDs;  Clinical Trials / Drug Trials;  Pharma Industry / Biotech Industry
Article Date: 13 Aug 2009 - 1:00 PDT

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Palatin Technologies, Inc. (NYSE Amex: PTN) announced the completion of a Phase 1 clinical trial of subcutaneously administered bremelanotide, its melanocortin agonist drug candidate for treatment of male erectile dysfunction (ED) and female sexual dysfunction (FSD). The results demonstrate that with subcutaneous administration consistent therapeutic blood plasma levels can be obtained without blood pressure side effects. Based on the positive results of this study, Palatin has scheduled a meeting with the U.S. Food and Drug Administration to discuss initiation of a Phase 2B study of subcutaneously administered bremelanotide for ED.

"This study supports our hypothesis that increases in blood pressure and gastrointestinal events seen with intranasally administered bremelanotide were primarily related to high plasma levels in a subset of patients. We believe this was due to variability in drug uptake with intranasal administration," said Trevor Hallam, Ph.D., Executive Vice President of Research and Development of Palatin. "The switch from intranasal to subcutaneous administration appears to address the blood pressure concerns raised by the FDA. Our next step is to put this data in front of the FDA as we prepare to move bremelanotide back into a Phase 2 study later this year."

Key Results

In all subjects, subcutaneous administration of bremelanotide resulted in consistent and predictable plasma concentrations at levels known from previous studies to improve erectile function. Other key results include:

-- No statistically significant difference in mean changes in blood pressure was seen in subjects receiving bremelanotide compared to placebo.

-- No clinically or statistically significant difference in the range of blood pressure changes was seen in subjects receiving bremelanotide compared to placebo.

-- No subject discontinued participation in the study as a result of protocol stopping rules based on blood pressure changes.

-- No subject discontinued participation in the study due to nausea.

-- No difference in the rate of vomiting observed between subjects receiving bremelanotide compared to placebo (one in each group).

Study Design

The two week randomized, double-blind, placebo-controlled Phase 1 study in 54 subjects (27 bremelanotide, 27 placebo) measured blood pressure at baseline and before and after each of 45 doses of bremelanotide or placebo administered subcutaneously. The dose administered was selected to result in a plasma level of bremelanotide known, from previous studies, to be efficacious for improving erectile function. Continuous ambulatory blood pressure data was also collected for the first 48 hours after the initial dose in all subjects.

Commercial Opportunity

"We are excited by the commercial opportunity for bremelanotide. About 35% of patients with ED do not respond to approved oral therapies, and with limited treatment options these patients are ideal candidates for subcutaneous bremelanotide," stated Carl Spana, Ph.D., President and CEO of Palatin. "We have an additional opportunity with FSD, which represents a large market opportunity with no FDA approved drugs."

About Bremelanotide

Bremelanotide, a synthetic peptide developed and solely owned by Palatin, is believed to act through activation of melanocortin receptors in the central nervous system. Intranasal formulations of bremelanotide have been extensively studied, including Phase 2B studies for ED in both non-diabetic and diabetic patients and Phase 2A studies for FSD in both pre- and post-menopausal women.

About Erectile Dysfunction (ED)

ED is 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 half of all men over the age of 40 and that 150 million men worldwide suffer from ED. Up to 35% of men with ED are non-responsive to standard therapies with phosphodiesterase-5 inhibitors, representing an estimated market of $500 to $600 million per year.

About Female Sexual Dysfunction (FSD)

FSD includes four disorders, hypoactive sexual desire disorder, female sexual arousal disorder, dyspareunia and anorgasmia. To establish a diagnosis of FSD, these syndromes must be associated with personal distress, as determined by the affected woman. A February 10, 1999 study published in the Journal of the American Medical Association, titled, "Sexual Dysfunction in the United States: Prevalence and Predictors," states that approximately 43% of postmenopausal women suffer from some form of FSD. There are no drugs in the United States approved for FSD indications.

About Palatin Technologies, Inc.

Palatin Technologies, Inc. is a biopharmaceutical company focused on discovering and developing targeted, receptor-specific small molecule and peptide therapeutics. Palatin's strategy is to develop products and then form marketing collaborations with industry leaders in order to maximize their commercial potential.

Forward-looking Statements

Statements about future expectations of Palatin Technologies, Inc., including statements about its development programs, proposed indications for its product candidates, clinical activities, marketing collaborations, and all other statements in this document other than historical facts, 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. Palatin's actual results may differ materially from those discussed in the forward-looking statements for various reasons, including, but not limited to Palatin's ability to fund development of its technology, ability to establish and successfully complete clinical trials and pre-clinical studies and the results of those trials and studies, dependence on its partners for certain development activities, need for regulatory approvals and commercial acceptance of its products, ability to protect its intellectual property, and other factors discussed in the 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.

Source: Palatin Technologies, Inc.