Palatin Technologies, Inc, a biopharmaceutical company developing targeted, receptor-specific peptide therapeutics, has  announced that its collaboration partner,  AstraZeneca has decided to discontinue further development of AZD2820, one of a number of collaboration compounds in various stages of development for the treatment of obesity. AstraZeneca remains committed to this collaboration programme and to the continued advancement of melanocortin agonists for treatment of obesity.

AZD2820, a subcutaneously-administered peptide melanocortin-4 receptor partial agonist, was a clinical candidate under development by AstraZeneca from a collaborative research program with Palatin Technologies. As previously announced, a phase I trial of AZD2820 was halted following a serious adverse event. The decision to discontinue development of the compound was made based on investigations and review conducted by AstraZeneca that followed this incident. While not confirmed, it could not be excluded that the serious adverse event was linked to AZD2820. The investigation further concluded that it is unlikely that the serious adverse event was related to melanocortin receptor activation as an approach for the treatment of obesity.

"We are pleased that the subject has fully recovered from this adverse event," said Dr. Carl Spana, president and CEO of Palatin. "The AZD2820 compound is part of a broader research and development collaboration with AstraZeneca. We have multiple classes of collaboration compounds in various stages of preclinical testing and AstraZeneca has informed us that they remain committed to the advancement of collaboration compounds for treatment of obesity."

Pursuant to the terms of the research collaboration and license agreement with AstraZeneca, Palatin is eligible for milestone payments upon achieving development and regulatory milestones and further payments on achievement of sales targets, in addition to royalties on sales of approved products. AstraZeneca has responsibility for product commercialization, product discovery and development costs.

Obesity is a global problem, with the World Health Organization estimating that over 1.5 billion adults are overweight and over 500 million are obese. A number of different metabolic and hormonal pathways are being evaluated by companies around the world in efforts to develop better treatments for obesity. Scientific research has established that melanocortin receptors have a role in eating behaviour and energy homoeostasis, and that some melanocortin receptor agonists decrease food intake and induce weight loss in animal studies.

In 2007, Palatin Technologies entered into an exclusive research collaboration and license agreement with AstraZeneca to discover, develop and commercialize compounds that target melanocortin receptors. Active development work by Palatin under the collaboration portion of the agreement concluded in January 2010.