Consensus statement for diagnosis and treatment of paroxysmal nocturnal haemoglobinuria

Consensus recommendations for optimising the diagnosis and treatment of paroxysmal nocturnal haemoglobinuria in Singapore

Introduction

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare haematologic disease characterised by intravascular haemolysis, thrombophilia and bone marrow failure. There is a lack of established clinical guidance on the screening, diagnosis and manage-ment of PNH in Singapore. A relatively low level of awareness among healthcare professionals regarding PNH manifestations further contributes to diagnostic delays. Additionally, limited access to complement inhibitors, like eculizumab, may delay treatment and impact patient outcomes.

Method

Nine haematologists from different institu-tions in Singapore convened to formulate evidence-based consensus recommendations for optimising the diagnosis and management of patients with PNH and improving access to novel treatments. The experts reviewed the existing literature and international guidelines published from January 2010 to July 2023, focusing on 7 clinical questions spanning PNH screening, diagnostic criteria, investigations, treatment and monitoring of subclinical and classic disease, PNH with underlying bone marrow disorders, and PNH in pregnancy. A total of 181 papers were reviewed to formulate the statements. All experts voted on the statements via 2 rounds of Delphi and convened for an expert panel discussion to finetune the recommendations.

Results

Sixteen statements have been formulated for optimising the screening, diagnosis and management of PNH. Upon confirmation of PNH diagnosis, individuals with active haemolysis and/or thrombosis should be considered for anti-complement therapy, with eculizumab being the only approved drug in Singapore.

Conclusion

The current recommendations aim to guide the clinicians in optimising the screening, diagnosis and management of PNH in Singapore.

Health-related quality of life and influencing factors of patients with paroxysmal nocturnal hemoglobinuria in China

BACKGROUND

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare blood disorder, leading to various complications and impairments in patients' health-related quality of life (HRQOL). Limited research has been conducted to evaluate the HRQOL of Chinese patients with PNH. Understanding the HRQOL in this specific population is crucial for providing effective healthcare interventions and improving patient' health outcomes. This study aimed to assess HRQOL of Chinese patients with PNH, and identify key determinants.

METHODS

A cross-sectional study was conducted during 2022 to recruit patients with PNH in China. The study population was recruited from PNH China, one of the largest public welfare PNH patient mutual aid organization in China. Data were collected via an online questionnaire including the EQ-5D-5L (5L), and social-demographic and clinical characteristics. Descriptive statistics were employed to summarize the characteristics of the participants and their HRQOL. Multiple linear and logistic regression analyses were adopted to explore key factors affecting HRQOL.

RESULTS

A total of 329 valid questionnaires were collected. The mean (SD) age of the patients was 35.3 (10.0) years, with 52.3% of them being male. The patients reported more problems in Anxiety/Depression (81.5%) and Pain/Discomfort (69.9%) dimensions compared to the other three 5L dimensions. The mean (SD) of 5L health utility score (HUS) and EQ-VAS score were 0.76 (0.21) and 62.61 (19.20), respectively. According to multiple linear regression, initial symptoms (i.e., Anemia [fatigue, tachycardia, shortness of breath, headache] and back pain) and complication of thrombosis were significant influencing factors affecting 5L HUS. Total personal income of the past year, initial symptom of hemoglobinuria and complication of thrombosis were significantly influencing factors of VAS score. Social-demographic and clinical characteristics, such as gender, income, and thrombosis, were also found to be significantly related to certain 5L health problems as well.

CONCLUSION

Our study manifested the HRQOL of PNH patients in China was markedly compromised, especially in two mental-health related dimensions, and revealed several socio-demographic and clinical factors of their HRQOL. These findings could be used as empirical evidence for enhancing the HRQOL of PNH patients in China.

Iptacopan: First Approval

Iptacopan (FABHALTA®) is an oral complement Factor B inhibitor developed by Novartis Pharmaceuticals for the treatment of complement-mediated diseases. Acting upstream of complement 5 in the alternative pathway, iptacopan inhibits both terminal complement-mediated intravascular haemolysis and complement 3-mediated extravascular haemolysis. On 5 December 2023, iptacopan received approval in the USA for the treatment of adults with paroxysmal nocturnal haemoglobinuria (PNH). This article summarizes the milestones in the development of iptacopan leading to this first approval for PNH.

Cutting-Edge Techniques and Drugs for the Treatment of Pulmonary Embolism: Current Knowledge and Future Perspectives

Pulmonary embolism (PE) is a potentially life-threatening condition requiring prompt diagnosis and treatment. Recent advances have led to the development of newer techniques and drugs aimed at improving PE management, reducing its associated morbidity and mortality and the complications related to anticoagulation. This review provides an overview of the current knowledge and future perspectives on PE treatment. Anticoagulation represents the first-line treatment of hemodynamically stable PE, direct oral anticoagulants being a safe and effective alternative to traditional anticoagulation: these drugs have a rapid onset of action, predictable pharmacokinetics, and low bleeding risk. Systemic fibrinolysis is suggested in patients with cardiac arrest, refractory hypotension, or shock due to PE. With this narrative review, we aim to assess the state of the art of newer techniques and drugs that could radically improve PE management in the near future: (i) mechanical thrombectomy and pulmonary embolectomy are promising techniques reserved to patients with massive PE and contraindications or failure to systemic thrombolysis; (ii) catheter-directed thrombolysis is a minimally invasive approach that can be suggested for the treatment of massive or submassive PE, but the lack of large, randomized controlled trials represents a limitation to widespread use; (iii) novel pharmacological approaches, by agents inhibiting thrombin-activatable fibrinolysis inhibitor, factor Xia, and the complement cascade, are currently under investigation to improve PE-related outcomes in specific settings.

Biomimetic proteolipid vesicles for reverting GPI deficiency in paroxysmal nocturnal hemoglobinuria

Nano-vesicular carriers are promising tissue-specific drug delivery platforms. Here, biomimetic proteolipid vesicles (BPLVs) were used for delivery of glycosylphosphatidylinositol (GPI)-anchored proteins to GPI deficient paroxysmal nocturnal hemoglobinuria (PNH) cells. BPLVs were assembled as single unilamellar monodispersed (polydispersity index, 0.1) negatively charged (ζ-potential, -28.6 ± 5.6 mV) system using microfluidic technique equipped with Y-shaped chip. GPI-anchored and not-GPI proteins on BPLV surface were detected by flow cytometry. Peripheral blood mononuclear cells (PBMCs) from healthy and PNH subjects were treated with BPLVs (final concentration, 0.5 mg/mL), and cells displayed an excellent protein uptake, documented by flow cytometry immunophenotyping and confocal microscopy. BPLV-treated cells stressed with complement components showed an increased resistance to complement-mediated lysis, both healthy and PNH PBMCs. In conclusion, BPLVs could be effective nanocarriers for protein transfer to targeted cells to revert protein deficiency, like in PNH disease. However, further in vivo studies are required to validate our preclinical in vitro results.

The disease burden of paroxysmal nocturnal hemoglobinuria in Denmark: Epidemiology, survival, healthcare resource utilization, costs, treatment gaps, and labor market attachment

OBJECTIVES

To establish epidemiology, healthcare costs, and labor market attachment in patients with paroxysmal nocturnal hemoglobinuria (Pt-PNH) in Denmark.

METHODS

Data were from Statistics Denmark and the Danish Health Data Authority national population registers (2005-2021). Descriptive baseline statistics characterized the Pt-PNH analytic population; ordinary least squares and adjusted Cox proportional hazards regressions measured outcomes in the Pt-PNH versus Danish general population matched comparators.

RESULTS

Overall PNH incidence in Denmark was n = 11 during 2007-2009, n = 25 during 2016-2018 and n = 7 during 2019-2020; prevalence increased from n = 13 in 2006 to n = 62 in 2021. Of the overall n = 85 Pt-PNH; n = 24 were treated with complement-5 inhibitors (Pt-C5i) and n = 61 not treated with C5i (Pt-nC5i). Versus respective comparators, all patients had significantly greater annual per-patient costs (from inpatient hospital admissions, outpatient contacts, PNH treatments; indirect costs from lost earnings + transfer payments; post-diagnosis for Pt-PNH and Pt-nC5i, post-treatment initiation for Pt-C5i). The Pt-C5i incurred the greatest healthcare and indirect cost differences (€709 119; €152 832, respectively) followed by the Pt-PNH (€189 323; €29 159, respectively) and Pt-nC5i (€95 548; €4713, respectively). The Pt-PNH versus comparators also had an increased hazard of death (2.71 [95% CI, 1.63 - 4.51]).

CONCLUSION

Although a rare disease, PNH is associated with significant patient, healthcare system, and societal burdens in Denmark.

Descriptive, real-world treatment patterns, resource use, and total cost of care among eculizumab- and ravulizumab-treated members with paroxysmal nocturnal hemoglobinuria

BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, genetic, chronic, and life-threatening blood disease with an estimated prevalence of 13 per 1,000,000 persons reported in the United States. Available at analysis, PNH treatment included the use of C5 inhibitors (C5is), which prevent formation of membrane attack complex and consequently intravascular hemolysis. Limited real-world evidence suggests some individuals with PNH continue to experience anemia and breakthrough hemolysis (BTH) after C5i treatment, indicating unmet needs. OBJECTIVE: To describe real-world treatment patterns and outcomes among individuals treated with C5is, eculizumab (ECU), and ravulizumab (RAV), focusing on affordability challenges and therapy unmet needs from a US payer perspective. METHODS: This retrospective cohort study was conducted using deidentified data from Prime Therapeutics' approximately 15 million commercially insured US members with integrated medical and pharmacy claims data. Members were identified between January 1, 2018, and December 31, 2020. Inclusion criteria for cohort identification were adults aged 18 years or older at ECU or RAV index date requiring 2 or more claims for ECU or 1 or more claims for RAV. ECU and RAV users were excluded if they had a claim indicating treatment for a US Food and Drug Administration (FDA)-approved non-PNH indication. Members were required to be continuously enrolled 6 months before and 12 months after their index ECU or RAV claim. Real-world C5i claims-based treatment dosage and frequency patterns were compared with FDA-labeled dosing. Clinical outcomes, including transfusions and BTH events, were identified in the pre-index and post-index periods. Health care resource use and costs were calculated after network discounts, including member share. RESULTS: A total of 86 commercial members met analysis criteria: 34 in the ECU cohort and 52 in the RAV cohort. The mean age was 42.6 years, and 54.6% were female. Estimated higher-than-label PNH-recommended dosage occurred in 38.2% of ECU and 9.6% of RAV members. In total, 29.4% of ECU and 17.3% of RAV members had 4 or more transfusions in the post-index period. Additionally, 29.4% of ECU and 13.5% of RAV members had 1 or more BTH episodes. Post-index period mean per member total health care costs were $711,785 among ECU members and $624,911 among RAV members, and C5i costs accounted for 79.7% and 85.6% of total health care costs, respectively. CONCLUSIONS: Although all members received at minimum FDA-approved dosages, transfusions and BTH events continue to occur for some members. These findings indicate potentially inadequate therapy responses in a substantial subset of C5i users, adding additional therapy costs to an already extremely expensive therapy. DISCLOSURES: This study was funded by Apellis Pharmaceuticals. Drs Broderick and Fishman report employment by Apellis Pharmaceuticals and own stock options. Dr Burke reports employment by Prime Therapeutics, LLC, which has received research funding from Apellis Pharmaceuticals. Dr Gleason reports employment by Prime Therapeutics, LLC, which has received research funding from Apellis Pharmaceuticals; serves on the advisory committee at the Institute for Clinical and Economic Review; and has served on the Board of Directors at the Academy of Managed Care Pharmacy.

Swiss Survey on current practices and opinions on clinical constellations triggering the search for PNH clones

This national survey investigated the current practice in Switzerland by collecting participants' opinions on paroxysmal nocturnal hemoglobinuria (PNH) clone assessment and clinical practice.

Aim

This study aimed to investigate clinical indications prompting PNH clones' assessment and physician's accessibility of a flow cytometry facility, and also to understand clinical attitudes on the follow-up (FU) of patients with PNH clones.

Methods

The survey includes 16 multiple-choice questions related to PNH and targets physicians with a definite level of experience in the topic using two screener questions. Opinion on clinical management was collected using hypothetical clinical situations. Each participant had the option of being contacted to further discuss the survey results. This was an online survey, and 264 physicians were contacted through email once a week for 5 weeks from September 2020.

Results

In total, 64 physicians (24.2%) from 23 institutions participated (81.3% hematologists and 67.2% from university hospitals). All had access to flow cytometry for PNH clone testing, with 76.6% having access within their own institution. The main reasons to assess for PNH clones were unexplained thrombosis and/or hemolysis, and/or aplastic anemia (AA). Patients in FU for PNH clones were more likely to be aplastic anemia (AA) and symptomatic PNH. In total, 61% of the participants investigated PNH clones repetitively during FU in AA/myelodysplastic syndromes patients, even when there was no PNH clone found at diagnosis, and 75% of the participants tested at least once a year during FU. Opinions related to clinical management were scattered.

Conclusion

The need to adhere to guidelines for the assessment, interpretation, and reporting of PNH clones emerges as the most important finding, as well as consensus for the management of less well-defined clinical situations. Even though there are several international guidelines, clear information addressing specific topics such as the type of anticoagulant to use and its duration, as well as the indication for treatment with complement inhibitors in some borderline situations are needed. The analysis and the discussion of this survey provide the basis for understanding the unmet needs of PNH clone assessment and clinical practice in Switzerland.

Treatment of eculizumab refractory paroxysmal nocturnal hemoglobinuria: A systematic review about current treatment options and future direction

Objectives

C5 inhibitors such as eculizumab and ravulizumab are the first-line treatment in the management of paroxysmal nocturnal hemoglobinuria (PNH). However, some patients develop novel symptoms as part of their treatment with eculizumab, and the disease is termed as eculizumab refractory PNH. The aim of this study was to conduct a systematic review on the available treatment modalities for the management of eculizumab refractory PNH.

Methods

Two authors independently searched two databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 70 studies were obtained: 4 out 70 studies were found to meet the inclusion criteria.

Results

Four studies were found to meet the inclusion criteria of our study. Two studies were published in 2021 and two studies were published in 2020. All four studies were multicenter clinical trials. Two studies were phase III clinical trials, one study was a phase II clinical trial, and one study was a phase I clinical trial. Two studies were about pegcetacoplan, one was about danicopan, and one was about iptacopan.

Conclusion

Based upon the findings of our systematic review, we recommend an individualized treatment plan based on the mechanism of eculizumab refractoriness and the mechanism of PNH breakthrough. This recommendation is subject to the available resources and clinical expertise available at different hospitals. More studies using study designs such as randomized controlled trials comparing multiple drugs should be performed to accurately assess the different medications and aid in designing guidelines of the management of eculizumab refractory PNH.

Level of evidence

Level I.

Biomarkers and laboratory assessments for monitoring the treatment of patients with paroxysmal nocturnal hemoglobinuria: Differences between terminal and proximal complement inhibition

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, life-threatening, acquired disease in which blood cells lacking complement regulatory proteins are destroyed because of uncontrolled complement activity. Since 2007, terminal complement inhibitors have revolutionized the treatment of this disease. However, patients treated with these inhibitors can still experience anemia because of C3-mediated extravascular hemolysis and clinically relevant levels of breakthrough or residual intravascular hemolysis. Proximal complement inhibitors, which are only just beginning to emerge, have the potential to address this problem by targeting components of the pathway upstream of C5, thereby protecting patients against both intra- and extravascular hemolysis. In this review, we describe different biomarkers that can be used to monitor complement pathway blockade and discuss key laboratory assessments for evaluating treatment efficacy. We also consider how these assessments are affected by each class of inhibitor and highlight how evolving treatment goals may influence the relative importance of these assessments.

Paroxysmal nocturnal hemoglobinuria: A rare case of recurrent episodes of icterus

In this work we describe a rare case of a patient with paroxysmal nocturnal hemoglobinuria (PNH) developed on the background of specific medical history of morbus Gilbert with chronically elevated bilirubin and recurrent attacks of macroscopic haematuria. We focus on a differential diagnosis of the disease, its obstacles, and treatment options.

Pegcetacoplan: A Review in Paroxysmal Nocturnal Haemoglobinuria

Subcutaneous pegcetacoplan (EMPAVELI® in the USA and ASPAVELI® in the EU) is the first complement component 3 (C3) inhibitor approved for the treatment of adults with paroxysmal nocturnal haemoglobinuria (PNH) in the USA, and in adults with PNH who are anaemic after ≥ 3 months of treatment with a C5 inhibitor in the EU. In the phase III PRINCE trial in adults with PNH who were anaemic and naïve to a complement inhibitor therapy, pegcetacoplan was superior to the control group (supportive care, excluding complement inhibitors) in achieving haemoglobin stabilization and reducing lactate dehydrogenase levels. Similarly, in the phase III PEGASUS trial in adults with PNH who had a haemoglobin level < 10.5 g/dL despite eculizumab therapy, pegcetacoplan was superior to eculizumab in improving haemoglobin levels. In both trials, pegcetacoplan also improved other clinical and haematological parameters of haemolysis, as well as quality of life (QOL) outcomes. Clinical benefits of pegcetacoplan were sustained for up to 48 weeks of treatment. Pegcetacoplan was generally well tolerated in patients with PNH, with its tolerability profile being similar in patients previously treated with eculizumab and in complement inhibitor-naïve patients. Long-term data would be beneficial to further support the safety profile of pegcetacoplan. Current evidence indicates that pegcetacoplan is a valuable treatment option for adults with PNH.

Portal vein thrombosis as the first presentation of paroxysmal nocturnal hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired clonal hematopoietic stem cell disorder, characterized by hemolytic anemia, bone marrow failure and thrombosis. Portal vein thrombosis (PVT) is relatively rare in patients with PNH. In this paper, we reported PVT as the first clinical presentation of PNH in a female patient. PVT related symptoms resolved after anticoagulation therapy.

Indications for medical antibiotic prophylaxis and potential targets for antimicrobial stewardship intervention: a narrative review

BACKGROUND

Most of the antimicrobial stewardship (AMS) literature has focused on antimicrobial consumption for the treatment of infections, for the prophylaxis of surgical site infection and for the prevention of endocarditis. The role of AMS for medical antibiotic prophylaxis (AP) has not been adequately addressed.

AIMS

To identify targets for AMS interventions for medical AP in adult patients.

SOURCES

Targeted searches were conducted in PubMed.

CONTENT

The various indications for medical AP and relevant evidence from practice guidelines are outlined. The following were identified as potential targets for AMS interventions: (a) addressing under-utilization of antibiotic-sparing strategies (e.g. for recurrent urinary tract infections, recurrent soft-tissue infections, recurrent exacerbations associated with bronchiectasis or chronic obstructive pulmonary disease), (b) reducing unnecessary AP beyond recommended indications (e.g. for acute pancreatitis, bite wounds, or urinary catheter manipulations), (c) reducing the use of AP with a broader spectrum than necessary, (d) reducing the use of AP for longer than the recommended duration (e.g. AP for prevention of osteomyelitis in open fractures or AP in high-risk neutropenia), (e) evaluating the role of antibiotic cycling to prevent the emergence of resistance during prolonged AP (e.g. in recurrent urinary tract infections or prophylaxis for spontaneous bacterial peritonitis), and (f) addressing research gaps regarding appropriate indications or antibiotic regimens for medical prophylaxis.

IMPLICATIONS

This review summarizes current trends in AP and proposes targets for AMS interventions.