Long-term real-world safety and effectiveness of arimoclomol in individuals with NPC: Outcomes from the US early access program over a 4-year period.

BACKGROUND

The United States-based Early Access Program (US EAP) provided access to arimoclomol for individuals with Niemann-Pick disease Type C (NPC) ineligible or unable to enroll in clinical trials, generating 4 years of real-world safety and effectiveness data.

METHODS

Participants were enrolled at 14 US sites. Investigators collected adverse events (AEs) and assessed disease severity using the 5-domain NPC Clinical Severity Scale (5DNPCCSS) at Baseline and follow-up visits as part of routine clinical care.

RESULTS

Among 109 participants, 53 (48.6%) were adults (≥18 years) and 71 (65.1%) received miglustat alongside arimoclomol. Mean (SD) arimoclomol exposure was 820 (539) days. Of 248 reported AEs, 17 events in 13 participants (12.8%) were treatment related. 5DNPCCSS scores remained relatively stable throughout the program, with mean (SD) total scores of 11.0 (6.15) at Baseline (n = 100) and 12.0 (7.32) at Year 4 (n = 22). Among participants with Baseline and Year 1 assessments, mean (SD) scores were 11.2 (6.33) at Baseline and 11.1 (6.63) at Year 1 (n = 78). Similar patterns were observed for those with Baseline and Year 2, Year 3, or Year 4 assessments. Rescored 4-domain NPCCSS (R4DNPCCSS) scores (calculated based on 5DNPCCSS data) showed comparable longitudinal trends.

CONCLUSION

The US EAP provides robust real-world evidence data up to 4 years, supporting the tolerability and effectiveness of arimoclomol in a broad NPC population, including adults and those not treated with miglustat. These findings complement and extend clinical trials results, reinforcing the role of arimoclomol, especially in combination with miglustat, as an important therapeutic option in routine clinical practice.