Improvements in hematologic markers and decreases in fatigue with pegcetacoplan for patients with paroxysmal nocturnal hemoglobinuria and mild or moderate anemia (hemoglobin ≥10 g/dL) who had received eculizumab or were naive to complement inhibitors.

BACKGROUND: Although complement component 5 inhibitors (C5is) eculizumab and ravulizumab improve paroxysmal nocturnal hemoglobinuria (PNH) outcomes, patients may experience persistent anemia. This post hoc analysis investigated whether the complement component 3-targeted therapy pegcetacoplan also improved hematologic outcomes and reduced fatigue in patients with PNH and mild/moderate anemia. METHODS: Patients with PNH and hemoglobin ≥10.0 g/dL at baseline of PADDOCK (N = 6), PRINCE (N = 8), and PEGASUS (N = 11) were included. Before receiving pegcetacoplan, PADDOCK and PRINCE patients were C5i-naive; PEGASUS patients had hemoglobin <10.5 g/dL despite stably dosed eculizumab. Hemoglobin concentrations, percentages of patients with concentrations ≥12 g/dL, and sex-specific normalization were assessed at baseline and after 16 weeks of pegcetacoplan, as were absolute reticulocyte counts (ARCs) and normalization and fatigue scores and normalization. RESULTS: From baseline to week 16, mean (SD) hemoglobin concentrations increased in C5i-naive patients (PADDOCK: 10.5 [0.4] to 12.7 [1.1] g/dL; PRINCE: 11.3 [1.0] to 14.0 [1.3] g/dL) and those with suboptimal eculizumab responses (PEGASUS: 10.2 [0.2] to 12.8 [2.6] g/dL). Percentage of patients with hemoglobin ≥12 g/dL increased (PADDOCK: 0 to 60.0% [3 of 5 patients]; PRINCE: 25.0% [2 of 8] to 87.5% [7 of 8]; PEGASUS: 0 to 72.7% [8 of 11]). Sex-specific hemoglobin normalization at week 16 occurred in 40.0% (2 of 5) (PADDOCK), 62.5% (5 of 8) (PRINCE), and 63.6% (7 of 11) (PEGASUS). In all studies, mean ARCs decreased from above normal to normal and ARC normalization increased. Mean Functional Assessment of Chronic Illness Therapy-Fatigue scores improved from below to above or near normal. Two patients had serious adverse events (PEGASUS: post-surgery sepsis, breakthrough hemolysis); breakthrough hemolysis resolved without study discontinuation. CONCLUSION: Patients with PNH and mild/moderate anemia who were C5i-naive or who had suboptimal hemoglobin concentrations despite eculizumab treatment had improved hematologic outcomes and reduced fatigue after initiating or switching to pegcetacoplan. TRIAL REGISTRATION: Trial registration numbers: PADDOCK (NCT02588833), PRINCE (NCT04085601; EudraCT, 2018-004220-11), PEGASUS (NCT03500549).

Thrombosis and meningococcal infection rates in pegcetacoplan-treated patients with paroxysmal nocturnal hemoglobinuria in the clinical trial and postmarketing settings.

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired hematologic disease characterized by complement-mediated hemolysis and thrombosis. Complement component 5 (C5) inhibitors have decreased PNH-related thrombosis rates and reduced mortality compared with those of age-matched controls. A small but significantly increased risk of life-threatening Neisseria infections, especially N meningitidis, represents a long-term safety risk of complement inhibition. Objectives: To evaluate the rates of thrombosis and meningococcal infections in patients with PNH treated with the complement component 3-targeted therapy pegcetacoplan. Methods: Cumulative patient-year exposure to pegcetacoplan was calculated, and thrombotic events and meningococcal infections were reviewed in 7 clinical trials and in the postmarketing setting. The clinical trial protocols and pegcetacoplan labeling required vaccination against Streptococcus pneumoniae, N meningitidis, and Haemophilus influenzae before pegcetacoplan use; the label allowed for prophylactic antibiotic use if pegcetacoplan must be administered before vaccination. Results: As of November 13, 2022, 464 patients with PNH had 619.4 patient-years of pegcetacoplan exposure in completed/ongoing clinical trials and the postmarketing setting. Seven thrombotic events were reported: 5 in clinical trials (2 in the same patient) and 2 in the postmarketing setting. The overall thrombosis rate was 1.13 events per 100 patient-years (clinical trials: 1.22 events/100 patient-years in 409.4 years; postmarketing: 0.95 events/100 patient-years in 210.0 years). No infections with meningococcal bacteria were reported. Conclusion: Event rates for thrombosis were comparable between pegcetacoplan and previously reported rates of C5 inhibitors in patients with PNH, and no cases of meningococcal infection were reported with pegcetacoplan. Continued follow-up is required.

Normalization of Hemoglobin, Lactate Dehydrogenase, and Fatigue in Patients with Paroxysmal Nocturnal Hemoglobinuria Treated with Pegcetacoplan.

BACKGROUND AND OBJECTIVES: We determined normalization rates for hemoglobin, lactate dehydrogenase (LDH), and fatigue in patients with paroxysmal nocturnal hemoglobinuria (PNH) treated with pegcetacoplan (PEG) in the PEGASUS (NCT03500549) and PRINCE (NCT04085601) phase III trials. METHODS: Enrolled patients had PNH and hemoglobin < 10.5 g/dL despite ≥ 3 months of eculizumab (ECU) [PEGASUS], or were complement component 5 (C5) inhibitor-naive, receiving supportive care only, with hemoglobin less than the lower limits of normal (LLN) [PRINCE]. Hematologic and fatigue normalization endpoints were hemoglobin greater than or equal to the LLN (females: 12 g/dL; males: 13.6 g/dL) in the absence of transfusion; LDH ≤226 U/L in the absence of transfusion; and Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue ≥ 43.6, the general population norm. Safety was assessed by investigators using standardized terms and definitions for seriousness and severity. RESULTS: Hemoglobin normalization occurred in 34.1% (14/41) of PEG-treated patients at Week 16 (randomized controlled period) in PEGASUS (vs. 0% [0/39] of ECU-treated patients) and in 45.7% (16/35) of PEG-treated patients at Week 26 in PRINCE (vs. 0% [0/18] of supportive care-treated patients). At Week 48 (open-label period) in PEGASUS, 24.4% of PEG-treated patients (PEG-to-PEG) and 30.8% of patients treated with ECU through Week 16 who switched to PEG through Week 48 (ECU-to-PEG) had hemoglobin normalization. Rates of LDH normalization in PEGASUS were 70.7% (PEG-treated patients) and 15.4% (ECU-treated patients) at Week 16, and 56.1% (PEG-to-PEG) and 51.3% (ECU-to-PEG) at Week 48. In PRINCE, 67.5% of PEG-treated patients at Week 26 had normalized LDH concentrations. Rates of FACIT-Fatigue score normalization in PEGASUS were 48.8% and 10.3% in PEG- and ECU-treated patients, respectively, at Week 16, and 34.1% and 51.3% in PEG-to-PEG- and ECU-to-PEG-treated patients, respectively, at Week 48. In PRINCE, 68.6% of PEG-treated patients and 11.1% of supportive care patients had FACIT-Fatigue score normalization at Week 26. PEG was safe and well tolerated. Injection site reactions, mostly mild, were the most common adverse event of special interest in PEG-treated patients in the PEGASUS randomized controlled period (36.6%) and in PRINCE (30.4%). CONCLUSION: PEG is superior to ECU and supportive care in hemoglobin, LDH, and FACIT-Fatigue score normalization for patients with PNH and persistent anemia despite ≥3 months of treatment with ECU, and in C5 inhibitor-naive patients. CLINICAL TRIAL REGISTRATION: The PEGASUS trial (NCT03500549) was registered on 18 August 2018, and the PRINCE trial (NCT04085601) was registered on 11 September 2019.

Safety and Efficacy of Pegcetacoplan in Adult Patients with Paroxysmal Nocturnal Hemoglobinuria over 48 Weeks: 307 Open-Label Extension Study.

INTRODUCTION: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, life-threatening disease characterized by complement-mediated hemolysis and thrombosis. Pegcetacoplan, the first targeted complement component 3 (C3) PNH therapy, was safe and efficacious in treatment-naive and pre-treated patients with PNH in five clinical trials. METHODS: The 307 open-label extension (OLE) study (NCT03531255) is a non-randomized, multicenter extension study of long-term safety and efficacy of pegcetacoplan in adult patients with PNH who completed a pegcetacoplan parent study. All patients received pegcetacoplan. Outcomes at the 48-week data cutoff (week 48 of 307-OLE or August 27, 2021, whichever was earlier) are reported. Hemoglobin concentrations, Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scores, and transfusion avoidance were measured. Hemoglobin > 12 g/dL and sex-specific hemoglobin normalization (i.e., male, ≥ 13.6 g/dL; female, ≥ 12 g/dL) were assessed as percentage of patients with data available and no transfusions 60 days before data cutoff. Treatment-emergent adverse events, including hemolysis, were reported. RESULTS: Data from 137 patients with at least one pegcetacoplan dose at data cutoff were analyzed. Mean (standard deviation [SD]) hemoglobin increased from 8.9 (1.22) g/dL at parent study baseline to 11.6 (2.17) g/dL at 307-OLE entry and 11.6 (1.94) g/dL at data cutoff. At parent study baseline, mean (SD) FACIT-Fatigue score of 34.1 (11.08) was below the general population norm of 43.6; scores improved to 42.8 (8.79) at 307-OLE entry and 42.4 (9.84) at data cutoff. In evaluable patients, hemoglobin > 12 g/dL occurred in 40.2% (43 of 107) and sex-specific hemoglobin normalization occurred in 31.8% (34 of 107) at data cutoff. Transfusion was not required for 114 of 137 patients (83.2%). Hemolysis was reported in 23 patients (16.8%). No thrombotic events or meningococcal infections occurred. CONCLUSION: Pegcetacoplan sustained long-term improvements in hemoglobin concentrations, fatigue reduction, and transfusion burden. Long-term safety findings corroborate the favorable profile established for pegcetacoplan. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT03531255.