A new study revealed there is no adverse events or safety concerns were identified in participants with PD treated with solriamfetol.
Excessive daytime sleepiness (EDS), a nonmotor symptom affecting 20%–60% of patients with Parkinson’s disease (PD), may be a manifestation of the primary pathology of PD and/or secondary to soporific effects of dopaminergic medication, coexisting sleep disorders, psychiatric comorbidities, autonomic dysfunction, and other unknown factors.
There is currently no approved pharmacologic treatment for EDS in PD in the United States (US) or European Union (EU). Solriamfetol, a dopamine/norepinephrine reuptake inhibitor, is approved in the US and EU (Sunosi™) to treat EDS in adults with narcolepsy (75–150 mg/d) or obstructive sleep apnea (OSA; 37.5–150 mg/d). Based on the unmet need for pharmacologic treatment for EDS in PD patients, this study sought to characterize the safety and efficacy of solriamfetol in this population.
Phase 2, double-blind, 4-week, crossover trial: adults with PD and EDS were randomized to sequence A (placebo, solriamfetol 75, 150, 300 mg/d), B (solriamfetol 75, 150, 300 mg/d, placebo), or C (placebo). Outcomes (safety/tolerability [primary]; Epworth Sleepiness Scale [ESS]; Maintenance of Wakefulness Test [MWT]) were assessed weekly. P values are nominal.
Common adverse events (n = 66): nausea (10.7%), dizziness (7.1%), dry mouth (7.1%), headache (7.1%), anxiety (5.4%), constipation (5.4%), dyspepsia (5.4%). ESS decreased both placebo (−4.78) and solriamfetol (−4.82 to −5.72; P > 0.05). MWT improved dose-dependently with solriamfetol, increasing by 5.05 minutes with 300 mg relative to placebo (P = 0.0098).
In conclusion, no new AEs or safety concerns were identified in participants with PD treated with solriamfetol, and there was no evidence that solriamfetol worsened PD motor symptoms. There were no statistical differences between solriamfetol and placebo on the ESS; however, a large placebo response was observed.
Source: Videnovic, A., Amara, A.W., Comella, C., Schweitzer, P.K., Emsellem, H., Liu, K., Sterkel, A.L., Gottwald, M.D., Steinerman, J.R., Jochelson, P., Zomorodi, K. and Hauser, R.A. (2021), Solriamfetol for Excessive Daytime Sleepiness in Parkinson’s Disease: Phase 2 Proof-of-Concept Trial. Mov Disord. https://doi.org/10.1002/mds.28702