ADOLOR BEGINS TRIAL OF DELTA OPIOID AGONIST

Adolor has initiated a multidose Phase I clinical trial of ADL5859, a novel, orally bioavailable delta opioid receptor agonist. The study is designed to investigate the safety, tolerability and pharmacokinetics of ADL5859 in healthy volunteers following twice-a-day dosing for seven days. This study follows the recent completion of a single-dose Phase I study that demonstrated that the compound was well absorbed following oral administration and was generally well tolerated. Completion of the multidose study is targeted for the third quarter of this year.

One of three opioid receptors, the delta receptor, has potential utility in a variety of indications, including the modulation of pain. Through a proprietary research platform based on cloned, human opioid receptors, Adolor has identified a series of novel, orally active delta agonists -- compounds that selectively stimulate the delta opioid receptor. Delta compounds may have a number of potential advantages, including an improved side effect profile, as compared with mu opioid receptor agonists. On the basis of preclinical evaluation in animal models of human conditions, one might expect a delta agonist to show effect in inflammatory pain, among other pain conditions. In addition, delta agonists are thought to modulate other biological processes that may manifest themselves in disease states or conditions such as overactive bladder and depression.

ADL5859 has already demonstrated activity in several preclinical studies. A second compound, ADL5747, is in preclinical development with an investigational new drug application targeted for submission by the end of the year. There are currently no selective delta agonists approved by the FDA, according to Adolor.