Chemical structures of Neu-P11 (a) and Neu-P5 (b).

structure from- http://www.sciencedirect.com/science/article/pii/S0731708512005304#gr1

ZURICH, Feb. 18, 2013 Neurim Pharmaceuticals announced today positive results from a phase II clinical study evaluating the efficacy and safety of Piromelatine (Neu-P11), a novel investigational multimodal sleep medicine developed for the treatment of patients with primary and co-morbid insomnia. The new results are from a recent double-blind, randomized, placebo controlled, parallel group, non-confirmatory, sleep-laboratory study. The study evaluated piromelatine compared to placebo in 120 adult primary insomnia patients ages 18 years and older. 

Piromelatine 20/50mg treatment for 4 weeks resulted in statistically significant and clinically meaningful improvements relative to placebo in key polysomnographic (PSG) parameters including Wake After Sleep Onset (WASO) (p=0.02 for both doses) and in particular WASO for the first 6 hours of sleep (WASO-6h) (p=0.0008 and p=0.04 for the 50 mg and 20 mg groups, respectively). Piromelatine 50 mg also improved Sleep Efficiency (SEF) (p=0.02), Total Sleep Time (TST) (p=0.02), Total Time Awake (TTA) (p=0.01) and time in NREM sleep (p=0.028) indicating beneficial effects on sleep maintenance. Subjective improvements relative to placebo in quality of sleep and total sleep time measured by the Pittsburg Sleep Quality Questionnaire (PSQI) were also observed, confirming the PSG findings. Piromelatine enhanced NREM sleep EEG delta power and significantly reduced beta power (p<0.05). The decrease in EEG beta activity, a marker of cortical arousal, is a physiological surrogate marker of the efficacy of Piromelatine in sleep maintenance. Piromelatine was generally safe and well tolerated, had no detrimental effects on next-day psychomotor performance (as assessed by the Digit Symbol Substitution Test (DSST)) for any dose group and no deleterious effects on sleep structure and architecture.

“Piromelatine demonstrates a good potential for the treatment of primary insomnia characterized by sleep maintenance disturbances as well as insomnia with psychiatric or medical co-morbidities,” said Prof. Nava Zisapel, CSO of Neurim. The study results will be presented at the 27th Annual Meeting of the Associated Professional Sleep Societies (APSS) -Sleep 2013 meeting in Baltimore.

PIROMELATINE (NEU-P11)

Piromelatine is a novel compound under development for the treatment of insomnia associated with pain.
Piromelatine is a melatonin agonist, serotonin 5-HT-1A and 5-HT-1D agonist. The compound binds to the MT1, 2 and 3 receptors which govern the body’s sleep-wake cycle and circadian rhythm. The sleep promoting, analgesic, anti-diabetic, antihypertensive, anti-neurodegenerative, anxiolytic and antidepressant effects of Piromelatine have been demonstrated in a series of relevant animal models.

Piromelatine is a multi-facet drug addressing a wide range of potential indications including, but not limited to, insomnia, IBS, neuropathy and fibromyalgia.
Neurim has recently completed a phase-II clinical trial to assess the efficacy and safety of Piromelatine in patients with primary insomnia.