SAN DIEGO, CA, USA I October 29, 2015 I Arena Pharmaceuticals, Inc. (NASDAQ: ARNA) announced today the initiation of patient dosing in a Phase 1b multiple-ascending dose clinical trial of APD371, a selective and potent agonist of the cannabinoid 2 (CB2) receptor.

This randomized, double-blind, placebo-controlled Phase 1b clinical trial will enroll approximately 36 healthy adults to evaluate the safety, tolerability and pharmacokinetics of multiple-ascending doses of APD371. In a previous single-ascending dose trial, APD371 demonstrated dose responsive exposure over the explored range of 10-400 mg with good tolerability at all doses.

“As with all of our other clinical-stage compounds, APD371 was internally discovered by Arena’s scientists,” said Harry F. Hixson, Jr., Arena’s interim Chief Executive Officer. “This is another demonstration of Arena’s expertise in discovering and developing differentiated drug candidates to address unmet medical needs.”

About APD371

APD371, an orally available agonist of the CB2 receptor, is an internally discovered investigational drug candidate that Arena is exploring for potential development in several indications, including pain. This compound, through its selectivity, is designed to provide pain relief without psychotropic effects and without the potential for dependence or abuse. Preclinical efficacy with APD371 has been shown in several animal models of pain.

About Arena Pharmaceuticals

Arena embraces the challenge of improving health by seeking to bring innovative medicines targeting G protein-coupled receptors to patients. Arena’s focus is discovering, developing and commercializing drugs to address unmet medical needs, and BELVIQ® (lorcaserin HCl) is Arena’s first internally discovered drug approved for marketing. Arena has US operations located in San Diego, California, and operations outside of the United States, including its commercial manufacturing facility, located in Zofingen, Switzerland. For more information, visit Arena’s website at www.arenapharm.com.

SOURCE: Arena Pharmaceuticals