Effects of zuranolone on next-day simulated driving in healthy adults.

Rationale: Zuranolone is an oral positive allosteric modulator of GABA_A receptors. Due to its central nervous system (CNS) activity, zuranolone may impact activities requiring complex cognition, including driving.

Objective: Evaluate the effect of zuranolone on simulated driving performance.

Methods: In this randomized, double-blind, active- and placebo-controlled, four-period crossover study, treatments included once-nightly zuranolone 50 mg on days 1-7, zuranolone 50 mg on days 1-6 and zuranolone 100 mg on day 7, zopiclone 7.5 mg on days 1 and 7, and placebo on days 1-7. Driving was assessed using a validated simulator. Primary endpoint was standard deviation of lateral position (SDLP), evaluated 9 h post-dose on days 2 and 8. Secondary endpoints included additional driving assessments, cognitive tests, pharmacokinetics, and safety.

Results: Healthy adults (N = 67) enrolled and received ≥ 1 dose. Zuranolone 50 mg increased SDLP versus placebo on days 2 (least squares mean difference [LSMD]: 7.4 cm; p < 0.0001) and 8 (LSMD: 4.6 cm; p = 0.0106). Zuranolone 100 mg evoked a larger increase in SDLP versus placebo on day 8 (LSMD 18.9 cm; p < 0.0001). Reduced performance in other driving assessments and cognition were observed with zuranolone 50 mg on day 2; many resolved by day 8. Despite the SDLP observations, most participants judged themselves capable of driving. Frequent adverse events (≥ 20%) were CNS-related; most were mild/moderate.

Conclusion: Zuranolone impaired simulated driving and reduced cognitive function versus placebo 9 h after administration. Although many impairments resolved after 7 days of dosing, driving remained impaired. These results may inform prescriber decision-making.