XP-0863 Phase 1b results and regulatory feedback support direct to Phase 3 registration study in both pediatric and adult patients with epilepsy
Xeris Pharmaceuticals, Inc. (NASDAQ:XERS), a specialty pharmaceutical company leveraging its novel technology platforms to develop and commercialize ready-to-use injectable and infusible drug formulations, today announced additional data from the Phase 1b study to evaluate a novel diazepam formulation (XP-0863) in healthy adult subjects. In April 2020, the Company reported positive preliminary topline results from this study. Complete results from this study were presented at the Fifteenth EILAT Conference on New Antiepileptic Drugs and Devices (EILAT XV) on July 27-30, 2020. These data were also presented to the U.S. Food and Drug Administration (FDA) during a recent end-of-Phase 1 interaction.
XP-0863 is a highly concentrated liquid diazepam for intramuscular (IM) injection that is intended for the treatment of seizure emergencies in patients ≥ 2 years of age, with partial onset or generalized convulsive seizures, who are identified jointly by their caregivers and physicians as suffering intermittent and periodic episodes of markedly increased seizure activity. XP-0863 uses the XeriSol™ platform technology to overcome the solubility problems associated with diazepam, reduces injection burden, provides comparable pharmacokinetics to diazepam rectal gel (Diastat®), and may support the prompt and full-dose drug delivery of diazepam during seizure emergencies.
The Phase 1b study was an open-label, weight-based dose, 3-treatment, 3-way crossover study in healthy adult subjects. This study aimed to investigate the pharmacokinetics, safety, and tolerability of two different weight-based doses of intramuscular XP-0863 when compared to a weight-based dose of Diastat rectal gel. Subjects were randomly allocated to a sequence of three treatments: XP-0863 IM (0.25 mg/kg), XP-0863 IM (0.125 mg/kg), or Diastat (0.2 mg/kg). The subjects' diazepam blood levels were monitored over 21 days after drug dosing. XP-0863 showed comparable pharmacokinetics to Diastat, with similar partial AUCs of XP=0863 (0.25 mg/kg) to Diastat early after dosing and with increased overall exposure (AUC0‑∞) when compared to Diastat (18800 h*ng/mL versus 10900 h*ng/mL, respectively). XP-0863 (0.25 mg/kg) had comparable Cmax when compared to Diastat (355 ng/mL versus 384 ng/mL, respectively). The weight-based doses of XP-0863 were safe and well tolerated, with minimal sedation and injection site reactions, and no serious adverse events occurred.
Complete results of the Phase 1b study were shared with the US FDA in an end-of-Phase 1 interaction. The FDA provided feedback that Xeris' drug development program for XP-0863 could advance directly into a Phase 3 registration study in both pediatric and adult patients with epilepsy.
"The unique pharmacokinetic profile of XP-0863 may provide clinical advantages for patients ≥ 2 years of age who need diazepam for seizure emergencies. The Phase 1b study results and successful FDA interactions provide both a predictable and expedited development roadmap for XP-0863 as a critical therapy for the epilepsy community," said Paul R. Edick, Xeris' Chairman and CEO. "Our novel diazepam formulation is another important demonstration of the application of our XeriSol technology across multiple therapeutic areas." Mr. Edick continued, "We believe that XP-0863 is valuable asset, and we look forward to finding a suitable development partner in order to initiate a Phase 3 registration study in the future."
For more information, visit www.xerispharma.com.