KemPharm initiated a phase 2 clinical trial evaluating KP1077 as a treatment for idiopathic hypersomnia (IH). 

KP1077 is comprised of serdexmethylphenidate (SDX), KemPharm’s prodrug of d-methylphenidate. SDX was recently granted Orphan Drug Designation by the US Food and Drug Administration for treating IH.

The phase 2 clinical trial is a double-blind, placebo-controlled, randomized-withdrawal, dose-optimizing, multi-center study evaluating the efficacy and safety of KP1077 for treating IH. 

KemPharm expects to enroll about 48 adult patients with IH in more than 30 centers in the United States. Part 1 of the trial will consist of a five-week open-label titration phase in which patients will be optimized to one of four doses of SDX (80, 160, 240, or 320 mg/day).

Part 2 of the trial is a two-week randomized, double-blind withdrawal phase, during which two-thirds of the trial participants will continue to an optimized dose while the remaining third will receive a placebo. 

Participants will also be assigned into two evenly divided cohorts. The first cohort will receive a single daily dose just before bedtime, and the second cohort will receive half the daily dose shortly after awakening and half the daily dose before bedtime. The optimal dose range and dosing regimen results will inform future phase 3 studies.

KamPharm’s phase 2 clinical trial’s primary goal is to assess SDX’s safety and tolerability. A major secondary efficacy endpoint is the change in Epworth Sleepiness Scale total score. Additional exploratory endpoints include the Patient Global Impression of Severity, the Clinical Global Impression of Severity, change in total score on the Idiopathic Hypersomnia Severity Scale, and a new scale to assess the symptoms and severity of “brain fog.”

“Initiation of the phase 2 clinical trial investigating KP1077 for the treatment of IH is a significant milestone for KemPharm and a key inflection point as we continue to pursue our strategic transformation to develop or acquire novel therapeutics designed to address a range of underserved rare diseases,” says Travis C. Mickle, PhD, president and CEO of KemPharm, in a release. “We believe the design of the phase 2 study will allow us to evaluate KP1077’s effect on several symptoms associated with IH, including excessive daytime sleepiness, extreme difficulty waking, and severe brain fog.”

KemPharm expects to report interim data from the trial as early as Q3 2023.

KP1077 may have the possibility of being used in combination with sodium oxybate-based products.

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