Anchored Indirect Treatment Comparison Finds Comparable Effects of Pegcetacoplan and Iptacopan in Paroxysmal Nocturnal Haemoglobinuria.

BACKGROUND

Paroxysmal nocturnal haemoglobinuria (PNH) is an ultra-rare, acquired non-malignant haematological disorder characterised by thrombosis risk, serious complications and debilitating symptoms in untreated patients.

OBJECTIVE

This anchored indirect treatment comparison (ITC) evaluated efficacy data between proximal complement 3 inhibitor (C3i) pegcetacoplan and factor B inhibitor, iptacopan, in patients with PNH previously treated with complement 5 inhibitors (C5i; eculizumab, ravulizumab).

METHODS

Respective pivotal studies provided patient-level trial data for pegcetacoplan (16-week PEGASUS [NCT03500549]) and published data for iptacopan (24-week APPLY PNH [NCT04558918]). Differences in study design, duration and statistical methods between PEGASUS and APPLY PNH necessitated the comparative analyses to be conducted on secondary measures based on haemoglobin (Hb) levels, absolute reticulocyte count (ARC), lactate dehydrogenase (LDH) levels, and patient-reported outcomes on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) scale scores. The availability of a common reference C5i treatment group in both PEGASUS and APPLY PNH studies allowed anchored ITC (Bucher method). Simulated treatment comparison (STC) assessed the robustness of the main analysis.

RESULTS

Overall, baseline characteristics of the populations in the PEGASUS and APPLY PNH studies were broadly comparable. Anchored ITC showed comparable outcomes (mean difference, [95% CI]) on change-from-baseline to end of study for pegcetacoplan versus C5i, and iptacopan versus C5i, respectively, across endpoints: Hb level (-0.49 g/dL [-1.78, 0.80]); ARC (-34.41 × 109/L [-90.02, 21.21]); LDH level (-115.16 U/L [-244.40, 14.01]); FACIT-Fatigue score (3.57 [-5.60, 12.73]). Finally, the STC produced results consistent with the main Bucher analyses across all clinical endpoints and patient-reported fatigue, providing similar point estimates and confidence intervals.

CONCLUSION

This anchored ITC, based on data from pivotal trials, did not indicate significant differences in clinical or patient-reported outcomes between pegcetacoplan and iptacopan in PNH treatment. The findings suggest that PNH treatment decisions should also consider individualised disease- and patient-related factors.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03500549.