Eculizumab reduces long-term relapse risk in AQP4-positive NMOSD

Results of a long-term post-hoc analysis support the long-term effectiveness and safety of eculizumab monotherapy in aquaporin-4 (AQP4)-positive NMOSD. Over 90% of patients who had experienced 1 or 2 relapses in the year prior to the start of the PREVENT trial remained relapse-free through 192 weeks of eculizumab monotherapy [1].

PREVENT was a randomised, double-blind phase 3 trial in which eculizumab was associated with a significantly lower risk of relapse than placebo among patients with AQP4-positive NMOSD and was well tolerated [2]. The presented long-term results centred on the 33 patients who received eculizumab as monotherapy during PREVENT and/or its open-label extension (OLE), for a total of 85.3 patient-years (PY). In PREVENT, 1 of these 33 patients had experienced an adjudicated relapse versus 7 of 13 with placebo alone.

After 192 weeks, 96.2% and 93.8% of patients who received eculizumab monotherapy or eculizumab with concomitant immunosuppressive therapy (IST), respectively, were relapse-free. No patients receiving eculizumab monotherapy were hospitalised for a relapse or started IST.

Eculizumab has generally been well tolerated in the short- and longer term in patients who received the drug in the PREVENT study and/or its ongoing OLE. The number of adverse events (AEs) after 192 weeks that were related to treatment with eculizumab monotherapy (PREVENT + OLE) were similar to placebo alone in PREVENT: 181.0 and 186.0 events per 100 PY, respectively. The infection rate was also similar: 174.1 versus 186.0 events per 100 PY. There were no meningococcal infections or deaths. Actually, there were less treatment-related serious AEs with eculizumab monotherapy than with placebo (5.7 vs 23.3 per 100 PY).

1. Pittock S, et al. Long-term efficacy and safety of eculizumab monotherapy in AQP4+ neuromyelitis optica spectrum disorder. MSVirtual 2020, Abstract FC01.01.
2. Pittock SJ, et al. N Engl J Med. 2019;381(7):614-25.