Mulherin, Brian

Introduction: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare and severe hematologic disorder caused by somatic mutation(s) in hematopoietic stem cells, which results in dysregulation of complement activation and complement-mediated hemolysis. Several complement inhibitors are approved for PNH, including the intravenous or subcutaneous C5 inhibitors (C5is) eculizumab, ravulizumab, and crovalimab; the subcutaneous self-administered C3 inhibitor pegcetacoplan; and the oral factor B inhibitor iptacopan and factor D inhibitor danicopan (as add-on therapy to a C5i). Although oral self-administered medications would be expected to lighten treatment burden over injectable medications in patients with PNH, adherence to anticomplement therapies is essential to maintain stable hematologic response while avoiding adverse events of breakthrough hemolysis and thrombosis. Real-world adherence to pegcetacoplan in patients with PNH was evaluated and compared with reported real-world adherence to long-term oral therapies for chronic conditions. Methods: A descriptive review of recent literature was conducted to summarize real-word oral medication adherence rates in chronic conditions. The Medical Subject Headings “compliance, medication” and “administration, oral” were applied in PubMed, and yielded reports on oral antidiabetic medications (OADs) in type 2 diabetes, oral anticoagulants (OACs) in atrial fibrillation (AF), and oral oncolytics in hematologic cancers; observational, real-world studies reporting medication adherence rates were reviewed and summarized. Adherence to pegcetacoplan therapy among patients with PNH in the US postmarketing setting was calculated as the percentage of patients who take pegcetacoplan as prescribed (adherence definition) based on the number of days patients had pegcetacoplan vials in their possession (dispensed) divided by the total number of days in a dispensing period (proportion of days covered) using central pharmacy prescription refill data. Results: In general, patients who take ≥80% of prescribed doses are considered adherent; using this definition, adherence rates among patients receiving long-term therapies for chronic conditions are typically 50% to 60% but vary greatly [Kleinsinger F. Perm J. 2018;22:18-033]. For example, reported OAD adherence rates in type 2 diabetes vary across countries (42% in Switzerland [Huber CA et al. Medicine (Baltimore). 2016;95:e3994] to 67% in Canada [Simard P et al. Acta Diabetol. 2015;52:547]) and by medication types (36.7% with thiazolidinediones to 47.3% with dipeptidyl peptidase 4-inhibitors [Farr AM et al. Adv Ther. 2014;31:1287]). OAC adherence rates in AF range widely (~40% to ~90%), differing across countries, patient populations (incident AF vs. post cardiovascular event), OAC types (warfarin, direct OACs), and follow-up period lengths. OAC adherence is also influenced by patient demographic and clinical characteristics and regional determinants in US Medicare beneficiaries [Hernandez I et al. J Am Heart Assoc. 2019;8:e011427]. Interestingly, an inverse relationship between oral medication adherence and dosing frequency is observed in chronic diseases in general (progressively decreasing adherence rates from once-daily to twice, 3-times, and 4-times daily dosing regimens [Coleman CI et al. J Manag Care Pharm. 2012;18:527]), and with OACs in AF [Vrijens B, Heidbuchel H. Europace. 2015;17:514]. As with other chronic conditions, nonadherence to oral oncolytics in hematologic cancers is more prevalent than suspected (32.7%) and associated with poorer clinical response [Noens L et al. Blood. 2009;113:5401], which can further increase the economic burden on patients [Dashputre AA et al. J Manag Care Spec Pharm. 2020;26:186]. Pegcetacoplan adherence for PNH in the US postmarketing setting from launch (2021) to date (2024) was estimated at 97%, well above the 80% threshold defining medication adherence in the literature. Conclusions: Real-world patients with PNH who self-administer pegcetacoplan subcutaneously have adherence rates exceeding the reported real-world adherence rates for oral medications in chronic conditions, especially those with high dosing frequencies. Retaining a stable hematologic response and preventing potentially life-threatening complications in PNH relies on continuous patient adherence to lifelong anticomplement therapies.

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, life-threatening disease characterized by complement-mediated hemolysis. OPERA is the first US longitudinal real-world study on C3 inhibitor therapy, known as pegcetacoplan. Methods: OPERA enrolled US patients with PNH, age ≥18, who were prescribed pegcetacoplan, and data were collected from routine care. Hemoglobin was reported by patients during regular follow-up (censored from transfusions). The Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue (0–52 score) and Patient-Reported Outcomes Measurement Information System scale for Cognitive Function Abilities (PROMIS-CF; 23.27–67.09 t-score) were completed electronically (low score = negative outcome). Patients self-reported incidence of healthcare resource utilization (HCRU). Results: By January 2024, 70 patients (mean age 44.6 years; 57.1% female) reported up to 9 months of pegcetacoplan treatment, with a median [IQR] follow-up of 6.6 [3.8] months. The latest reported hemoglobin levels improved by a mean (SD) of 2.6 (1.9) g/dL from baseline. At 3, 6 and 9 months, patients reported clinically meaningful improvements (≥5 points) in FACIT-F (53.3–69.0%) and (≥2 points) PROMIS-CF (46.7–55.2%). Patients reported a <10% incidence rate per person month of all HCRU events. Conclusions: This first longitudinal real-world US study indicates a positive trend in Hb, fatigue, and cognition with limited HCRU during pegcetacoplan treatment in adults with PNH.

Introduction: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired hematologic condition characterized by complement-mediated, life-threatening hemolysis and thrombosis which are associated with significant impacts on health-related quality of life (HRQoL). Pegcetacoplan is the first targeted complement component 3 (C3) therapy approved for adults with PNH (US) and adults with PNH plus anemia despite receiving a complement component 5 inhibitor (C5i) for ≥3 months (EU). In clinical trials including patients with PNH who were C5i-experienced or -naive, pegcetacoplan significantly improved levels of hemoglobin (Hb) and lactate dehydrogenase (LDH) and reduced transfusion burden. Pegcetacoplan had a favorable safety profile in parent studies and an ongoing long-term, rollover, open-label extension study (NCT03531255). Compliance with pegcetacoplan treatment was high across all clinical studies. In the US real-world OPERA and Adelphi PNH Disease Specific Programme™ (DSP) patient-reported outcomes (PRO) studies, improvements in levels of Hb and LDH, along with self-reported fatigue and cognitive outcomes, were observed. Pegcetacoplan treatment also led to reductions in the frequency and severity of PNH symptoms (including shortness of breath and fatigue) and improvements in social, physical, and emotional HRQoL domains in the US real-world Voice of the Patient PRO study. Further, both patient and physician satisfaction with pegcetacoplan treatment was high in the Adelphi PNH DSP study. However, to date, compliance and safety with pegcetacoplan treatment in the real-world setting have not been described. The objective of this real-world evidence review study was to evaluate compliance and safety with pegcetacoplan treatment in patients with PNH in the US post-marketing setting. Methods: Post-marketing data from the US, including the number of patients who received pegcetacoplan and reported safety events, were collected and analyzed from the pegcetacoplan Risk Evaluation and Mitigation Strategies (REMS) program which controls the distribution of pegcetacoplan and the pharmacovigilance safety database through May 13, 2023. Treatment compliance was calculated as the proportion of days a patient had the drug in possession, divided by the total number of days of follow-up, using central pharmacy prescription refill data. Thrombosis (a leading cause of death in patients with PNH prior to the availability of complement inhibitors) and meningococcal infections (a potential risk with complement inhibitors) were safety events of interest. To reduce the risk of serious meningococcal infections, clinical trial protocols and pegcetacoplan labeling required vaccination against Streptococcus pneumoniae; N meningitidis types A, C, W, Y, and B; and Haemophilus influenzae type B before starting treatment with pegcetacoplan. If pegcetacoplan treatment must be initiated before vaccination, the US label mandates prophylactic antibiotic use. In this study, the rates of thrombosis and meningococcal infection per 100 patient-years were estimated based on the total number of thrombosis and meningococcal infection events reported in the REMS program. Results: As of May 13, 2023, the cumulative pegcetacoplan exposure was 273.10 patient-years in the US post-marketing setting. Based on prescription refill data, compliance with pegcetacoplan treatment was ~98%. There were 2 confirmed thrombotic events reported and the incidence of thrombotic events was 0.73 events/100 patient-years in 273.10 patient-years. Similar to clinical trials, no meningococcal infections were reported in the US post-marketing setting. Conclusions: The high compliance rate and favorable safety profile of pegcetacoplan in the US post-marketing setting were consistent with clinical trial observations. These data, coupled with the effectiveness on hematologic parameters and improvements in symptoms and HRQoL reported in pegcetacoplan real-world PRO studies, support a positive benefit:risk profile for pegcetacoplan in the real-world setting.