BACKGROUND

Ravulizumab, a long-acting anti-C5 antibody, was approved for atypical hemolytic uremic syndrome (aHUS) in September 2020 in Japan. Post-marketing surveillance was mandated by local regulatory authorities to evaluate the effectiveness and safety of ravulizumab in patients with aHUS in real-world clinical practice.

METHODS

Patients with aHUS who switched from eculizumab to ravulizumab and received at least one dose of ravulizumab between September 2020 and December 2021 were enrolled. The effectiveness was evaluated by thrombotic microangiopathy (TMA) event-free status, defined as no sign of TMA recurrence and no initiation of plasma therapy/dialysis during ravulizumab treatment. The safety of ravulizumab was evaluated by summarizing the incidence of adverse events (AEs) and serious AEs.

RESULTS

This study included 33 patients (19 children and 14 adults). The median (range) duration of eculizumab treatment before the switch was 1233 (113-3240) days, and the duration of ravulizumab treatment was 351 (127-365) days. During ravulizumab treatment, TMA event-free status was achieved in 97.0% (32/33) of patients. The platelet count, lactate dehydrogenase levels, and serum creatinine levels remained stable during ravulizumab treatment. Twenty-nine AEs were reported in 13 patients, including nine serious AEs in seven patients. No meningococcal infections or deaths occurred during ravulizumab treatment. One patient discontinued treatment and died 478 days later from an unknown cause.

CONCLUSIONS

This study confirmed the effectiveness and safety of ravulizumab in Japanese patients with aHUS after switching from eculizumab in a real-world setting.