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.

Hemolysis events in the phase 3 PEGASUS study of pegcetacoplan in patients with paroxysmal nocturnal hemoglobinuria.

ABSTRACT: Patients with paroxysmal nocturnal hemoglobinuria (PNH) experience complement-mediated intravascular hemolysis leading to anemia, fatigue, and potentially life-threatening thrombotic complications. Pegcetacoplan, a C3 inhibitor, demonstrated sustained improvements in hematologic and clinical parameters in the phase 3 PEGASUS trial in patients with PNH who remained anemic despite C5 inhibitor therapy. The present post hoc analysis describes 26 hemolysis adverse events (AEs) experienced in 19 patients during pegcetacoplan therapy in PEGASUS and baseline patient characteristics potentially associated with increased hemolysis risk. Lactate dehydrogenase (LDH) ≥2× the upper limit of normal (ULN) was observed in 19 events, including 2 with LDH ≥10× ULN. All patients experienced decreased hemoglobin during hemolysis (mean decrease, 3.0 g/dL). In 16 events (62%), a potential complement-amplifying condition underlying the event could be identified. Hemolysis AEs led to study discontinuation in 5 patients. However, of 26 hemolysis AEs, 17 (65%) were manageable without pegcetacoplan discontinuation. A greater proportion of patients with hemolysis AEs (n = 19) had key characteristics of higher disease activity at baseline compared to patients without hemolysis AEs (n = 61), namely higher-than-label eculizumab dose (53% vs 23%), detectable CH50 (total complement function; 74% vs 54%), and ≥4 transfusions in the previous 12 months (68% vs 51%). These characteristics may be useful predictors of potential future hemolysis events. This trial was registered at www.ClinicalTrials.gov as #NCT03500549.

Oral Iptacopan Monotherapy in Paroxysmal Nocturnal Hemoglobinuria.

BACKGROUND: Persistent hemolytic anemia and a lack of oral treatments are challenges for patients with paroxysmal nocturnal hemoglobinuria who have received anti-C5 therapy or have not received complement inhibitors. Iptacopan, a first-in-class oral factor B inhibitor, has been shown to improve hemoglobin levels in these patients. METHODS: In two phase 3 trials, we assessed iptacopan monotherapy over a 24-week period in patients with hemoglobin levels of less than 10 g per deciliter. In the first, anti-C5-treated patients were randomly assigned to switch to iptacopan or to continue anti-C5 therapy. In the second, single-group trial, patients who had not received complement inhibitors and who had lactate dehydrogenase (LDH) levels more than 1.5 times the upper limit of the normal range received iptacopan. The two primary end points in the first trial were an increase in the hemoglobin level of at least 2 g per deciliter from baseline and a hemoglobin level of at least 12 g per deciliter, each without red-cell transfusion; the primary end point for the second trial was an increase in hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. RESULTS: In the first trial, 51 of the 60 patients who received iptacopan had an increase in the hemoglobin level of at least 2 g per deciliter from baseline, and 42 had a hemoglobin level of at least 12 g per deciliter, each without transfusion; none of the 35 anti-C5-treated patients attained the end-point levels. In the second trial, 31 of 33 patients had an increase in the hemoglobin level of at least 2 g per deciliter from baseline without red-cell transfusion. In the first trial, 59 of the 62 patients who received iptacopan and 14 of the 35 anti-C5-treated patients did not require or receive transfusion; in the second trial, no patients required or received transfusion. Treatment with iptacopan increased hemoglobin levels, reduced fatigue, reduced reticulocyte and bilirubin levels, and resulted in mean LDH levels that were less than 1.5 times the upper limit of the normal range. Headache was the most frequent adverse event with iptacopan. CONCLUSIONS: Iptacopan treatment improved hematologic and clinical outcomes in anti-C5-treated patients with persistent anemia - in whom iptacopan showed superiority to anti-C5 therapy - and in patients who had not received complement inhibitors. (Funded by Novartis; APPLY-PNH ClinicalTrials.gov number, NCT04558918; APPOINT-PNH ClinicalTrials.gov number, NCT04820530.).

Management of acute breakthrough hemolysis with intensive pegcetacoplan dosing in patients with PNH.

ABSTRACT: Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement-mediated intravascular hemolysis leading to anemia, fatigue, and potentially life-threatening thrombotic complications. Breakthrough hemolysis (BTH) was first described in patients with PNH treated with terminal complement C5 inhibitors when intravascular hemolysis reoccurred despite treatment. Pegcetacoplan, the first proximal complement C3 inhibitor, offers broad hemolysis control in patients with PNH. While experience of managing BTH on C5 inhibitors is documented, very limited guidance exists for proximal complement inhibitors. This interim analysis assessed the effect of intensive treatment with pegcetacoplan following an acute BTH event in a subset of patients enrolled in the ongoing open-label extension study of pegcetacoplan in PNH. Thirteen patients with acute BTH included in the analysis received either a single IV dose of 1080 mg (n = 4) or 1080 mg subcutaneous (SC) dosing on 3 consecutive days (n = 9). A potential, clinically-relevant complement-amplifying condition, such as infection or vaccination, was reported in approximately half of the patients experiencing an acute BTH. Lactate dehydrogenase (LDH) levels decreased between day 1 and day 2 in 8 of 12 evaluable patients and in all 13 patients at day 7 to 12. Nine of 13 patients (69%) achieved LDH <2× the upper limit of normal by day 14 to 19. All adverse events associated with the acute BTH event were considered resolved by the investigators. Overall, intensive treatment with pegcetacoplan was safe and well tolerated. These novel data support effective management of acute BTH events in patients on pegcetacoplan with intensive IV or SC pegcetacoplan dosing. This trial was registered at www.clinicaltrials.gov as #NCT03531255.

Real-world experience of pegcetacoplan in paroxysmal nocturnal hemoglobinuria.

Pegcetacoplan significantly improves outcomes for patients with paroxysmal nocturnal hemoglobinuria (PNH) experiencing extravascular hemolysis (EVH) on eculizumab, leading to approval in 2021/2022 (USA/Europe). We report the first collaborative real-world evidence on pegcetacoplan use in UK and France. A total of 48 patients were either currently receiving or previously received pegcetacoplan (2019-2023). A total of 12 patients had participated in the PEGASUS clinical trial, continuing treatment after trial completion. Five patients were on combination treatment of C5 inhibition and pegcetacoplan. Mean pegcetacoplan duration was 20.2 months. Indication for pegcetacoplan was EVH on C5 inhibitors (Eculizumab, n = 29, Ravulizumab n = 16, others n = 3) with 35/48 patients requiring blood transfusion within the previous 12 months. Mean hemoglobin and reticulocyte count at pegcetacoplan commencement and after 3 months: 91 g/L and 205 × 109/L and 115.8 g/L and 107 × 109/L, respectively, resulting in mean Hb change of 22.3 g/L. Mean LDH pre- and post-pegcetacoplan was unchanged. Six patients have stopped pegcetacoplan. A total of 32 breakthrough hemolysis (BTH) events occurred in 13/48 patients. A total of 14 events were within clinical trials (reported separately). Six patients experienced 18 acute BTH events outside clinical trials, 7/18 associated with complement activating conditions. Successful clinical management included daily pegcetacoplan subcutaneously for 3 days or single eculizumab doses; these events are manageable with prompt intervention. Pegcetacoplan is effective for patients with PNH experiencing EVH. In this large patient cohort, treatment was well tolerated with improved hemoglobin and reticulocytes and maintained LDH control. Although BTH occurs, this is manageable by acute dose modification, with the majority of patients being maintained on pegcetacoplan.

Guidelines for the diagnosis and management of adult aplastic anaemia: A British Society for Haematology Guideline.

Pancytopenia with hypocellular bone marrow is the hallmark of aplastic anaemia (AA) and the diagnosis is confirmed after careful evaluation, following exclusion of alternate diagnosis including hypoplastic myelodysplastic syndromes. Emerging use of molecular cyto-genomics is helpful in delineating immune mediated AA from inherited bone marrow failures (IBMF). Camitta criteria is used to assess disease severity, which along with age and availability of human leucocyte antigen compatible donor are determinants for therapeutic decisions. Supportive care with blood and platelet transfusion support, along with anti-microbial prophylaxis and prompt management of opportunistic infections remain key throughout the disease course. The standard first-line treatment for newly diagnosed acquired severe/very severe AA patients is horse anti-thymocyte globulin and ciclosporin-based immunosuppressive therapy (IST) with eltrombopag or allogeneic haemopoietic stem cell transplant (HSCT) from a matched sibling donor. Unrelated donor HSCT in adults should be considered after lack of response to IST, and up front for young adults with severe infections and a readily available matched unrelated donor. Management of IBMF, AA in pregnancy and in elderly require special attention. In view of the rarity of AA and complexity of management, appropriate discussion in multidisciplinary meetings and involvement of expert centres is strongly recommended to improve patient outcomes.

Treatment outcomes of complement protein C5 inhibition in 509 UK patients with paroxysmal nocturnal hemoglobinuria.

ABSTRACT: Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematopoietic disorder that occurs on a background of bone marrow failure (BMF). In PNH, chronic intravascular hemolysis causes an increase in morbidity and mortality, mainly because of thromboses. Over the last 20 years, treatment of PNH has focused on the complement protein C5 to prevent intravascular hemolysis using the monoclonal antibody eculizumab and more recently ravulizumab. In the United Kingdom, all patients are under review at 1 of 2 reference centers. We report on all 509 UK patients with PNH treated with eculizumab and/or ravulizumab between May 2002 and July 2022. The survival of patients with eculizumab and ravulizumab was significantly lower than that of age- and sex-matched controls (P = .001). Only 4 patients died of thromboses. The survival of patients with PNH (n = 389), when those requiring treatment for BMF (clonal evolution to myelodysplastic syndrome or acute leukemia or had progressive unresponsive aplastic anemia) were excluded, was not significantly different from that of age- and sex-matched controls (P = .12). There were 11 cases of meningococcal sepsis (0.35 events per 100 patient-years). Extravascular hemolysis was evident in patients who received treatment, with 26.7% of patients requiring transfusions in the most recent 12 months on therapy. Eculizumab and ravulizumab are safe and effective therapies that reduce mortality and morbidity in PNH, but further work is needed to reduce mortality in those with concomitant BMF.