Comparative Effectiveness of Pegcetacoplan Versus Ravulizumab and Eculizumab in Complement Inhibitor-Naïve Patients with Paroxysmal Nocturnal Hemoglobinuria: A Matching-Adjusted Indirect Comparison

Abstract

Introduction: In the absence of head-to-head trials, this study compared treatment outcomes with the C3 complement inhibitor pegcetacoplan versus the C5 complement inhibitor eculizumab or ravulizumab in complement inhibitor-naïve patients with paroxysmal nocturnal hemoglobinuria (PNH).

Methods: A matching-adjusted indirect comparison was conducted using individual patient data from the pegcetacoplan arm of the PRINCE trial (NCT04085601; n = 34) and aggregate data from the ravulizumab (n = 125) and eculizumab (n = 121) arms of the ALXN1210-PNH-301 trial (NCT03056040). Clinical and quality of life endpoints were evaluated after matching patients in the two trials on baseline characteristics. The weighted Wald test with 95% confidence interval was used to compare categorical and continuous variables (i.e., weighted chi-squared and z tests, respectively). Bias factor analysis was performed to quantify the extent of residual bias from unmeasured confounders.

Results: After weighting, treatment with pegcetacoplan was associated with statistically significant improvements in most clinical endpoints compared with ravulizumab or eculizumab treatment. These included: greater absolute and percent reductions in lactate dehydrogenase (LDH) level and increase in hemoglobin level from baseline; shorter time to first occurrence of LDH normalization; larger proportions of patients achieving hemoglobin stabilization and avoiding transfusion, with fewer packed red blood cell units transfused; and a smaller proportion of patients experiencing breakthrough hemolysis (all p < 0.05). Patients receiving pegcetacoplan also had a greater increase in general health status score from baseline compared with those receiving C5 complement inhibitors.

Conclusion: Pegcetacoplan provides clinical benefits as first-line treatment for complement inhibitor-naïve patients with PNH.

Trial registration: ClinicalTrials.gov identifier, NCT04085601.

Keywords: C3/C5 complement inhibitor; Clinical trial; Hemolytic disease; Matching-adjusted indirect comparison; Paroxysmal nocturnal hemoglobinuria (PNH); Transfusion; Treatment outcome.