Profile: Palatin Technologie Inc (PTN.A)

Palatin Technologies, Inc. (Palatin), incorporated in 1986, is a biopharmaceutical company engaged in the development of peptide, peptide mimetic and small molecule compounds with a focus on melanocortin and natriuretic peptide receptor systems. The Company has a diverse pipeline of development programs, including development of proposed products for treatment of heart failure (HF), sexual dysfunction, obesity, diabetes and metabolic syndrome. As of June 30, 2009, Palatin’s products under development included bremelanotide, a peptide melanocortin receptor, for treatment of sexual dysfunction, targeting female sexual dysfunction (FSD) and erectile dysfunction (ED) in patients non-responsive to current therapies, PL-6983, a peptide melanocortin receptor agonists, for treatment of sexual dysfunction; PL-3994, a peptide mimetic natriuretic peptide receptor A (NPRA) agonist, for treatment of HF and melanocortin receptor-based compounds for treatment of obesity and related metabolic syndrome pursuant to an ongoing research collaboration and global license with AstraZeneca AB (AstraZeneca).

Bremelanotide for Sexual Dysfunction

Palatin is developing subcutaneously administered bremelanotide for the treatment of ED and FSD. Bremelanotide, a melanocortin agonist (which promotes a biologic function response) drug candidate, is a synthetic peptide analog of the naturally occurring hormone alpha-MSH (melanocyte-stimulating hormone). Bremelanotide acts through activation of melanocortin receptors in the central nervous system, which is a different mechanism of action from currently marketed PDE-5 inhibitor ED therapies that act directly on the vascular system.

PL-6983 for Treatment of Female Sexual Dysfunction

PL-6983 is the Company’s lead compound in a new series of melanocortin receptor-specific peptides developed by it. The Company has demonstrated efficacy of PL-6983 in inducing erections in animal models and in inducing sexual behavior in an animal model of FSD. In developing PL-6983, the Company used a screening platform that examined the effectiveness of peptides in animal models of sexual response and also determined cardiovascular effects, primarily looking at changes in blood pressure. In these animal models, PL-6983 resulted in significantly smaller increases in blood pressure at doses effective for a sexual response than blood pressure increases in the same models seen with bremelanotide.

Obesity

During the fiscal year ended June 30, 2007 (fiscal 2007), the Company entered into an exclusive global licensing and research collaboration agreement with AstraZeneca to discover, develop and commercialize compounds that target melanocortin receptors for the treatment of obesity, diabetes and related metabolic syndrome. In June and December 2008, the collaboration agreement was amended to include additional compounds and associated intellectual property developed by the Company. The Company has developed classes of small molecule and peptide compounds targeting melanocortin receptors, which are effective in the treatment of obesity in animal models. Certain of these compounds have been demonstrated to be effective in normal diet-induced obese and genetically obese animal models for decreasing food intake and body weight, without an increase in sexual response in normal animals at the same or higher dose levels.

PL-3994 for Heart Failure Indications

PL-3994 is an NPRA agonist compound in development for treatment of HF. PL-3994 is one of a number of natriuretic peptide receptor agonist compounds the Company has developed. PL-3994 is a synthetic molecule incorporating an amino acid mimetic structure. It has an extended half-life, with reduced affinity for endogenous natriuretic peptide clearance receptors and significantly increased resistance to neutral endopeptidase, an endogenous enzyme that degrades natriuretic peptides. Pre-clinical studies in animals established a dose-dependent effect on blood pressure and diuresis, and in animal models of HF showed improved kidney function and prevention of cardiac hypertrophy (increase in heart size due to disease). Safety toxicology studies were conducted in animals prior to filing an investigational new drug (IND) application with the United States Food and Drug Administration (FDA).

Human clinical studies of PL-3994 commenced with a Phase I trial, which concluded during the fiscal year ended June 30, 2008 (fiscal 2008). This was a randomized, double-blind, placebo-controlled, study in 26 healthy volunteers who received either PL-3994 or a placebo subcutaneously. The evaluations included safety, tolerability, pharmacokinetics and several pharmacodynamic endpoints, including levels of cyclic guanosine monophosphate (cGMP), a natural messenger nucleotide. Dosing concluded with the achievement of the primary endpoint of the study, a pre-specified reduction in systemic blood pressure. During fiscal 2008, the Company conducted a Phase IIa trial in volunteers with controlled hypertension who were receiving one or more conventional antihypertensive medications. In this trial, which was a randomized, double-blind, placebo-controlled, single-ascending dose study in 21 volunteers, the objective was to demonstrate that PL-3994 can be given safely to patients taking antihypertensive medications commonly used in HF and hypertension patients. Dosing concluded with the achievement of the primary endpoint of the study, a pre-specified reduction in systemic blood pressure.