EPX-100 - (ARGUS)

September 3, 2026: Harmony Biosciences Holdings, Inc. (NASDAQ: HRMY) said it will present encore data on EPX-100 (clemizole hydrochloride) at the 16th European Epilepsy Congress in Athens, Greece, September 5-9, 2026.

EPX-100 is being developed for Dravet syndrome and Lennox-Gastaut syndrome. The company said the ongoing ARGUS trial in Dravet syndrome and LIGHTHOUSE trial in Lennox-Gastaut syndrome are currently enrolling.

The congress presentations are:

• EPX-100 as adjunctive therapy in patients with Dravet syndrome: preliminary results from the open-label extension phase of the ARGUS study (Poster P0342), scheduled for September 6, 2:00-3:00 pm EEST.
• A drug-drug interaction study of EPX-100 with clinical probe substrates for selected CYP enzymes (Poster P0331), also scheduled for September 6, 2:00-3:00 pm EEST.

No efficacy or safety results were disclosed in this announcement beyond noting that preliminary ARGUS open-label extension results and CYP interaction data will be presented.