A new paroxysmal nocturnal hemoglobinuria (PNH) registry analysis has found that, although some intergroup differences were observed, combined use of eculizumab and immunosuppressive therapy (IST) was safe and effective. The analysis, published in Acta Haemotologica, noted that the positive results were observed regardless of the treatment sequence.

“Despite what is known about treating patients with eculizumab and IST separately, limited data exist in patients with [aplastic anemia-PNH] who may require treatment with both eculizumab and IST,” the authors wrote. “Here, we describe the results of an analysis that used patient data from the International PNH Registry to evaluate the real-world effectiveness and safety of eculizumab in the context of a treatment sequence with IST.”

The research team analyzed data from 181 patients with PNH who were enrolled in the International PNH Registry. They were divided into 2 groups: those receiving IST followed by concomitant eculizumab (n=138) and those taking eculizumab followed by concomitant IST (n=43). An additional 87 patients received IST alone.

The results showed no significant differences between the groups in the effectiveness or safety of eculizumab. Hematological parameters such as platelet and reticulocyte counts and hemoglobin levels improved in most patients, with the exception of those who started IST after the initiation of eculizumab.

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The authors caution that there was heterogeneity within the 3 patient groups, such as differences in the size of population of PNH cells at diagnosis or the presence of PNH cells in patients with aplastic anemia, which could have affected the degree of response to each of the therapies.  

The observational nature of the registry and the rarity of PNH limit the ability to generalize the results. However, the data offer real-world evidence that builds on additional recent publications that have supported concomitant therapy with eculizumab and IST in smaller PNH patient populations.


Hill A, de Latour RP, Kulasekararaj AG, et al. Concomitant immunosuppressive therapy and eculizumab use in patients with paroxysmal nocturnal hemoglobinuria: an international PNH registry analysis. Acta Haematol. 2023;146(1). doi:10.1159/000526979