Neurogen Corp, Branford, Conn, today released positive top-line results from two dose-ranging, Phase 2b clinical trials in chronic insomnia patients with the company’s proprietary insomnia agent, NG2-73, an alpha-3 preferring GABA(A) partial agonist.

“We are very pleased with the results of these studies,” said William H. Koster, PhD, president and CEO of Neurogen. “We wanted to answer two questions in these trials. First, can we achieve our target profile in chronic insomnia patients of rapid onset of sleep which is maintained throughout the night without next-day residual effects and, second, do we have a controlled release formulation of the drug that we believe we can take forward? The results of these studies indicate the answer to both questions is yes.”

The objective of the first trial—Study 202—was to measure efficacy in sleep maintenance, or the ability to maintain sleep throughout the night after falling asleep. In this study, NG2-73 achieved statistically significant results versus placebo at all doses tested.

The objective of the second trial—Study 203—was to demonstrate efficacy in sleep onset, or the amount of time it takes to fall asleep, in chronic insomnia patients. In this study, NG2-73 achieved statistically significant results with participants falling asleep an average of 47.1 minutes to 56.4 minutes sooner, compared with the placebo group, which fell asleep an average of 23.2 minutes sooner.

In both studies, NG2-73 was safe and well tolerated at all doses tested. One drug-related Serious Adverse Event (SAE) was observed. The favorable safety and tolerability profile of NG2-73 observed in studies 202 and 203 was consistent with that observed in previous studies. NG2-73 has now been tested in more than 600 subjects.

Neurogen shares fell 14 cents, or 2%, to $6.84 in afternoon trading.