Irish biopharmaceutical firm Jazz Pharmaceuticals has reported positive efficacy results from the Phase III TONES 2 clinical trial of JZP-110 to treat adults with narcolepsy-associated excessive sleepiness.

JZP-110 is a selective dopamine and norepinephrine reuptake inhibitor (DNRI).

Results from the 12-week, four-arm, parallel-group, double-blind, placebo-controlled, randomised TONES 2 trial showed statistically significant improvement in the co-primary endpoints of the maintenance of wakefulness test (MWT) and the epworth sleepiness scale (ESS).

The trial assessed the safety and efficacy of 300mg, 150mg and 75mg of JZP-110 in 240 patients over a period of 12 weeks.

"The adverse events (AEs) observed in the TONES 2 trial were found to be consistent with those observed in prior Phase II trials of JZP-110 in narcolepsy."

Jazz Pharmaceuticals research and development global head and chief medical officer Karen Smith said: "Excessive sleepiness in narcolepsy remains an important unmet medical need, and we believe that the statistically and clinically significant effect observed in this study indicates that JZP-110 could be an important treatment option for patients.

"Subject to completion of the data analysis and our regulatory discussions with FDA, we expect to submit the JZP-110 NDA for excessive sleepiness in obstructive sleep apnea and narcolepsy in late-2017."

The secondary endpoints of the patient global impression of change (PGIc) scale at doses of 300mg and 150mg were also found to be favourable in comparison to placebo.

The adverse events (AEs) observed in the TONES 2 trial were found to be consistent with those observed in prior Phase II trials of JZP-110 in narcolepsy.

The TONE 2 trial is part of the TONES Phase III programme, which includes three other clinical trials, two of which are inobstructive sleep apnea (OSA), and one open-label study for long-term safety and efficacy maintenance.