The European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) issued a negative opinion on July 23, 2026, recommending refusal of the Marketing Authorization Application (MAA) for arimoclomol (Meplyffa) submitted by Zevra Therapeutics (Nasdaq: ZVRA) for the treatment of Niemann-Pick disease type C (NPC) in patients aged two years and older in combination with miglustat. The Boston-based company has since requested a formal re-examination of the opinion. Zevra Therapeutics
The CHMP's rationale, published in the EMA's assessment report, centered on insufficient demonstration of efficacy. The agency concluded that uncertainties in data handling and analytical approach undermined the reliability of the pivotal trial results. Specifically, the committee found no benefit in ambulation or cognition domains, and while a subgroup of patients also receiving miglustat showed a treatment effect favoring arimoclomol, the CHMP did not consider this finding robust given the absence of a demonstrated effect in the overall study population. The pivotal trial enrolled 50 children and adolescents aged 2 to 18 years.
Arimoclomol received US FDA approval in September 2024 as the first approved treatment for NPC in the United States, indicated in combination with miglustat for neurological manifestations of the disease in patients aged two years and older. In Europe, treatment options for NPC neurological manifestations include miglustat (Zavesca) and Aqneursa (levacetylleucine), which received EU marketing authorization in January 2026 for patients aged six years and older weighing at least 20 kg. Aqneursa is indicated in combination with miglustat or as monotherapy when miglustat is not tolerated. The negative CHMP opinion leaves arimoclomol without EU marketing authorization, although compassionate-use access continues in countries where national authorities have authorized such programs.
The NPC treatment landscape is becoming more active. Thousand Oaks, California-based Beren Therapeutics P.B.C. has an NDA for adrabetadex under FDA Priority Review for infantile-onset NPC, with a PDUFA target action date of November 17, 2026. Adrabetadex targets the underlying cholesterol trafficking defect via a distinct cyclodextrin-based mechanism and carries an infantile-onset-specific indication, positioning it as complementary rather than directly competitive with arimoclomol in the near term.