NEUROGEN ANNOUNCES START OF DENTAL PAIN DRUG STUDY

Neurogen has announced that Merck, through an affiliate, has begun a Phase II proof-of-concept clinical trial to study the investigational pain drug MK-2295 (NGD-8243). MK-2295 is one of several drug candidates Merck is developing as part of its exclusive worldwide alliance with Neurogen to develop oral medicines targeting the type 1 vanilloid receptor.

The initiation of the Phase II study triggers a $3 million milestone payment from Merck to Neurogen. The companies will select the most promising of the lead candidates for further development once proof-of-concept has been established.

The Phase II trial is a randomized, double-blind, placebo-controlled study designed to determine the efficacy of MK-2295 in the treatment of postoperative dental pain. In single-ascending-dose Phase I trials, MK-2295 was potent, and active at the VR1 target and generally well-tolerated with no serious adverse events. Multiple-ascending-dose studies are ongoing.

Neurogen's exclusive worldwide alliance with Merck to research, develop and commercialize next-generation drugs for the treatment of pain and other disorders began in 2004. The partnership enables Merck and Neurogen to pool drug candidates targeting VR1, a key integrator of pain signals in the nervous system, and combine their ongoing VR1 programs to form a global research and development collaboration.