Zevra Therapeutics, Inc. announced top-line data from its placebo-controlled, double-blind Phase 2 clinical trial (NCT05668754) evaluating the safety and tolerability of KP1077 (serdexmethylphenidate, or SDX) in patients with idiopathic hypersomnia (IH). This proof-of-concept study was not powered to demonstrate statistical significance. The data gathered for several secondary and exploratory endpoints, including the Epworth Sleepiness Scale (ESS), Idiopathic Hypersomnia Severity Scale (IHSS) and Sleep Inertia Visual Analog Scale (SIVAS) will inform the Phase 3 study design.

The company look forward to presenting the final results of the Phase 2 trial at the upcoming SLEEP 2024 annual meeting. Due to its unique pharmacokinetic profile, adverse events were mostly mild in severity despite higher overall exposure levels when compared to both immediate and long-acting methylphenidate products currently used off-label for the treatment of IH. Topline results of the Phase 2 study include: KP1077 produced clinically meaningful improvement in excessive daytime sleepiness (EDS), as assessed by change from baseline in the Epworth Sleepiness scale (ESS), that was maintained during both the five-week open-label titration period and throughout the 2-week double-blind withdrawal period for both dosing regimens.

Patients administered KP1077 showed benefits in change from baseline for the IH Severity Scale (IH SS), Sleep Inertia Visual Analog scale (SIVAS) and Brain Fog severity Scale (BFS) at the end of the open-label dose titration, and at the end of the double-blind withdrawal period. The results from the completed Phase 2 trial provide key information for the design of a potentially pivotal Phase 3 trial of KP1077 in patients with IH. The Company plans to request an end-of-Phase 2 (EOP2) meeting with the U.S. Food and Drug Administration to seek guidance on the Phase 3 clinical trial design.

The Phase 2 clinical trial was a double-blind, placebo-controlled, randomized-withdrawal, dose-optimizing, multi-center study that evaluated the safety and efficacy of KP1077 for the treatment of IH; Part 1 of the trial consisted of a five-week open-label dose titration phase during which patients were optimized to one of four doses of KP1077 (80, 160, 240, or 320 mg/day). KP1077 has been granted Orphan Drug Designation by the U.S. Food & Drug Administration (FDA) for the treatment of IH, and the U.S. Drug Enforcement Agency (DEA) has classified SDX, the sole API in KP1077, as a Schedule IV controlled substance based on evidence suggesting SDX has a lower potential for abuse when compared to d-MPH, a Schedule II controlled substance. Forward-looking statements include all statements that do not relate solely to historical or current facts, including without limitation statements regarding the promise and potential impact of preclinical or clinical trial data; the design, initiation, timing and results of any clinical trials or readouts; interpretations of trial data outcomes on clinical safety and efficacy; Zevra's reports regarding or presentation of trial data, including at conferences and other events, including at conferences, and the company's reports regarding or presentations of the trial data, including at conferences.