Excessive Sleep Therapy For OSA Marks Strong Phase 3 Results

An investigational selective dopamine norepinephrine reuptake inhibitor has shown promising effects on sleepiness in obstructive sleep apnea (OSA) patients.

Solriamfetol (JZP-110), the trial therapy from Jazz Pharmaceuticals, was tested for its treatment of the common OSA symptom, excessive sleepiness (ES) in a phase 3 trial. The results were published at the 2017 Annual CHEST Meeting in Toronto, ON, CA, this week.

The US-based study, led by Gary K. Zammit, PhD, president and chief executive officer of research organization Clinilabs, sought out JZP-110’s effect on ES in nearly 500 OSA patients. Criteria for the study included adults-only, with current or prior primary OSA treatment use.

Participants were also required to score at least 10 on the Epworth Sleepiness Scale (ESS), average less than 30 minutes on the first 4 trials of a 5-trial, 40-minute Maintenance and Wakefulness Test (MWT), and sleep at least 6 hours nightly on average.

A total of 474 patients were randomized into once-daily oral 37.5mg, 75mg, 150mg, 300mg JZP-110 tablets, or placebo. They were also stratified by adherence or non-adherence to primary OSA therapy.

Through 12 weeks, the 4 JZP-110 treatment groups reported significant and regimen-based improvement in least square mean MWT score change from baseline. The groups scored 4.7 min, 9.1 min, 11 min, and 13 min for 37.5mg, 75mg, 150mg, 300mg, respectively. The placebo group reported a least square mean score change of 0.2 min.

All JZP-110 treatment dosage groups aside from 75mg also reported a high rate of improvement on the Patient Global Impression of Change scale (PCI-G). Both 150mg (89.7%) and 300mg (88.7%) had nearly 90% of its patients report a PCI-G improvement in the 12 weeks.

Overall, treatment groups also reported improved ESS scores However, there were reports of adverse events (AE) in about two-thirds of the treated population.

While 47.9% of placebo patients reported AEs, 67.9% of JZP-110-treated patients reported AEs. Treatment group patients also doubled the placebo patients (4:2) in serious AEs, though none of the events were deemed related to the study drug. Over 10% of JZP-110 patients reported headaches. Another 7.9% reported nausea, 7.6% decreased appetite, and 7% anxiety.

Researchers concluded that JZP-110 still showed a consistent tolerability profile to its phase 2 trial results in narcolepsy patients. It was also a significant, but dose-dependent, therapy for MWT-based wakefulness, and effective in improving ESS and PGI-C.