Objectives: The complement component 5 (C5) inhibitor ravulizumab demonstrated non-inferiority to eculizumab following 26 weeks of treatment in complement inhibitor-naïve and complement inhibitor-experienced patients with paroxysmal nocturnal hemoglobinuria (PNH; studies 301 and 302, respectively). This study aims to describe the results of both studies from 27 weeks to 2 years.Methods: Patients (N = 441) continued to receive ravulizumab throughout the extension period. Efficacy endpoints included lactate dehydrogenase (LDH) normalization, transfusion avoidance and fatigue score (FACIT-F). Safety analyses were also performed.Results: From 27 weeks to 2 years, improvements in LDH levels were maintained in both study populations. Transfusion avoidance was maintained in 81.9% (study 301) and 85.6% (study 302) of patients, and FACIT-F scores remained stable. Ravulizumab was well tolerated, and the incidence of adverse events (AEs) were similar between patients of both studies. Incidence of serious AEs deemed related to ravulizumab treatment was low (<3%).Conclusions: This study reports, to date, the longest period of follow-up in over 400 patients with PNH treated with ravulizumab (662 patient-years). Long-term, ravulizumab demonstrated durable efficacy and was well tolerated, highlighting the importance of C5 inhibitors as the mainstay of PNH treatment.

MYH9-related disorders (MYH9-RDs) caused by mutation of the MYH9 gene which encodes non-muscle myosin heavy-chain-IIA (NMMHC-IIA), an important motor protein in hemopoietic cells, are the most commonly encountered cause of inherited macrothrombocytopenia. Despite distinguishing features including an autosomal dominant mode of inheritance, giant platelets on the peripheral blood film accompanied by leucocytes with cytoplasmic inclusion bodies (döhle-like bodies), these disorders remain generally under-recognized and often misdiagnosed as immune thrombocytopenia (ITP). This may result in inappropriate treatment with corticosteroids, immunosupressants and in some cases, splenectomy. We explored the efficacy of next generation sequencing (NGS) with a candidate gene panel to establish the aetiology of thrombocytopenia for individuals who had been referred to our center from hematologists in the Australasian region in whom the cause of thrombocytopenia was suspected to be secondary to an inherited condition but which remained uncharacterized despite phenotypic investigations. Pathogenic MYH9 variants were detected in 15 (15/121, 12.4%) individuals and the pathogenecity of a novel variant of uncertain significance was confirmed in a further two related individuals following immunofluorescence (IF) staining performed in our laboratory. Concerningly, only one (1/17) individual diagnosed with MYH9-RD had been referred with this as a presumptive diagnosis, in all other cases (16/17, 94.1%), a diagnosis was not suspected by referring clinicians, indicating a lack of awareness or a failing of our diagnostic approach to these conditions. We examined the mean platelet diameter (MPD) measurements as a means to better identify and quantify platelet size. MPDs in cases with MYH9-RDs were significantly larger than controls (p < 0.001) and in 91% were greater than a previously suggested threshold for platelets in cases of ITP. In addition, we undertook IF staining in a proportion of cases and confirm that this test and/or NGS are satisfactory diagnostic tests. We propose that fewer cases of MYH9-RDs would be missed if diagnostic algorithms prioritized IF and/or NGS in cases of thrombocytopenia associated with giant platelets, even if döhle-like bodies are not appreciated on the peripheral blood film. Finally, our report describes the long-term use of a thrombopoietin agonist in a case of MYH9-RD that had previously been diagnosed as ITP, and demonstrates that treatment with these agents may be possible, and is well tolerated, in this group of patients.

BackgroundThe evolution of molecular studies in myeloproliferative neoplasms (MPN) has enlightened us the understanding of this complex disease consisting of polycythaemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The epidemiology is well described in the western world but not in Asian countries like Malaysia.Materials and methodsThis retrospective national registry of MPN was conducted from year 2009 to 2015 in Malaysia.ResultsA total of 1010 patients were registered over a period of 5 years. The mean age was 54 years with male predominance. The ethnic distribution revealed that Chinese had a relatively high weighted incidence proportion (43.2%), followed by Indian (23.8%), Malay (15.8%) and other ethnic groups (17.2%). The types of MPN reported were 40.4% of ET (n = 408), 38.1% of PV (n = 385), 9.2% of PMF (n = 93), 3.1% of hypereosinophilic syndrome (HES) (n = 31) and 7.9% of unclassifiable MPN (MPN-U) (n = 80). Splenomegaly was only palpable clinically in 32.2% of patients. The positive JAK2 V617F mutation was present in 644 patients with 46.6% in PV, 36.0% in ET, 9.0% in PMF, and 7.4% in MPN-U, and had significantly lower haemoglobin (p < 0.001), haematocrit (p < 0.001) and white blood cells (WBC) (p < 0.001) than those with negative mutation. Significant differences in platelet and WBC count were detected in ethnic groups and MPN sub-types. There were more arterial thrombosis events seen in those with JAK2 V617F mutation as compared to venous thrombosis events (23.1% vs 4.4%). The bleeding rate was only 6.6%. Among the risk factors, previous thrombosis, old age (≥ 60 years) and hypertension were significantly correlated to positive JAK2 V617F mutation. The arterial thrombosis event is associated with higher presenting HB, HCT and PLT while the bleeding event is associated with lower presenting HB, HCT but higher PLT. The presence of JAK2 V617F mutation is associated with higher risk of arterial thrombosis.ConclusionChinese ethnicity is associated with higher rates of MPN. The history of thrombosis, age ≥ 60 years and hypertension are risk factors that can be correlated to JAK2 V617F mutation. This study is instrumental for policy makers to ensure preventive strategies can be implemented in future.

Coronavirus disease (COVID-19) has a wide spectrum of clinical manifestations. In this case report, we describe our first case of COVID-19 pneumonia that was complicated by cerebral venous thrombosis and bleeding in a patient with polycythemia vera. Madam A, a 72-year-old lady with polycythemia vera, ischemic stroke, hemorrhoids, diabetes mellitus, hypertension, and dyslipidemia was admitted to the hospital for COVID-19 pneumonia. She was treated with hydroxychloroquine and lopinavir/ ritonavir as per hospital protocol. She continued taking hydroxyurea and aspirin for her treatment of polycythemia vera. Subsequently, she developed rectal bleeding when her platelet count was 1247 × 10 3 /μl, even though she was not on an anticoagulant. Her aspirin was withheld. One week later, she was readmitted to the hospital for cerebral venous thrombosis and her D-dimer was 2.02 μg/ml. She was commenced on a therapeutic dose of low molecular weight heparin. Following that, her D-dimer level showed a decreasing trend and normalized upon her discharge. Patients with polycythemia vera are prone to develop thrombotic and bleeding complications. Management of this group of patients has become more complex with COVID-19 infection. It is crucial for us to decide when to start an anticoagulant especially when there is a history of recent bleeding. We need to balance the risks of further bleeding versus potentially fatal thrombotic events. Studies have shown that D-dimer can be used as a clinical marker to predict thrombotic events in COVID-19 infection. Patients with COVID-19 infection and polycythemia vera will benefit from both pharmacological thromboprophylaxis and close monitoring for bleeding.

Introduction: β-thalassemia is an inherited hemoglobinopathy associated with an erythroid maturation defect characterized by ineffective erythropoiesis and impaired RBC maturation. Luspatercept is a first-in-class erythroid maturation agent under development to treat patients with β-thalassemia. Luspatercept binds to select TGFβ superfamily ligands to reduce aberrant Smad2/3 signaling and enhance late-stage erythropoiesis (Suragani RN, et al. Nat Med. 2014;20:408-14). We report the results of a phase 3, randomized, double-blind, placebo-controlled study to determine the efficacy and safety of luspatercept in adult β-thalassemia patients requiring regular RBC transfusions. ClinicalTrials.gov identifier: NCT02604433. Methods: Eligible patients were aged ≥ 18 years; had β-thalassemia or hemoglobin (Hb) E/β-thalassemia (compound β-thalassemia mutation and/or multiplication of α-globin genes was allowed); and required regular transfusions of 6-20 RBC units in the 24 weeks prior to randomization with no transfusion-free period ≥ 35 days during that time. Patients were randomized 2:1 to receive either luspatercept, at a starting dose level of 1.0 mg/kg with titration up to 1.25 mg/kg, or placebo, subcutaneously every 3 weeks for ≥ 48 weeks. Patients in both treatment arms continued to receive RBC transfusions and iron chelation therapy to maintain the same baseline Hb level. The primary endpoint was a ≥ 33% reduction in transfusion burden (with a reduction of ≥ 2 RBC units) during weeks 13-24, when compared with a 12-week baseline period. Key secondary endpoints included: ≥ 33% reduction in RBC transfusion burden at weeks 37-48, ≥ 50% reduction in transfusion burden at weeks 13-24, ≥ 50% reduction in transfusion burden at weeks 37-48, and mean change in transfusion burden at weeks 13-24. Achievement of ≥ 33% reduction in RBC transfusion burden over any consecutive 12 weeks on study was also evaluated. Results: † A total of 336 patients were randomized, of whom 332 were treated. Median age was 30 years (range 18-66) and 58% of patients were female. Patients received a median of 6 RBC units in the 12 weeks prior to treatment. 58% of patients in each arm had undergone splenectomy. B0/B0 genotype (classification according to the HbVar database) was observed in 68 of 224 (30.4%) and 35 of 112 (31.3%) patients in the luspatercept and placebo arms, respectively. 48 of 224 (21.4%) patients in the luspatercept arm achieved the primary endpoint versus 5 of 112 (4.5%) patients receiving placebo (odds ratio 5.79, P < 0.0001). 44 of 224 (19.6%) patients receiving luspatercept achieved a ≥ 33% reduction in RBC transfusion burden at weeks 37-48 compared with 4 of 112 (3.6%) patients receiving placebo (P < 0.0001). Of 224 patients receiving luspatercept, 17 (7.6%) and 23 (10.3%) achieved a ≥ 50% reduction in RBC transfusion burden at weeks 13-24 and 37-48, respectively, compared with 2 (1.8%) and 1 of 112 (0.9%) patients receiving placebo (P = 0.0303 and P = 0.0017, respectively). The difference of mean change from baseline in transfusion burden from week 13 to week 24 was 1.35 units (P < 0.0001). 158 of 224 (70.5%) patients receiving luspatercept achieved a ≥ 33% RBC transfusion reduction over any consecutive 12 weeks compared with 33 of 112 (29.5%) patients receiving placebo (P < 0.0001); statistically significant differences were also noted for all other transfusion burden reduction endpoints. Adverse events (AEs) observed in the study were generally consistent with previously reported phase 2 data. Treatment-emergent AEs leading to dose delay or dose reduction were similar between treatment arms. No patient deaths were reported for those treated with luspatercept. Conclusions: Treatment with luspatercept resulted in significant reductions in RBC transfusion burden in adults with transfusion-dependent β-thalassemia. Luspatercept was generally well tolerated in this patient population. † As of May 11, 2018, cutoff date. Disclosures Cappellini: Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; Sanofi/Genzyme: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria; Vifor: Membership on an entity's Board of Directors or advisory committees. Viprakasit:F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Agios: Consultancy, Research Funding; Protagonist Therapeutics: Consultancy, Research Funding. Taher:Protagonist Therapeutics: Consultancy; Novartis: Consultancy, Honoraria, Research Funding; Ionis Pharmaceuticals: Consultancy; La Jolla Pharmaceutical: Research Funding; Celgene Corp.: Research Funding. Georgiev:Alnylam: Consultancy. Coates:Celgene Corp.: Consultancy; ApoPharma: Consultancy, Honoraria; Vifor Pharma: Consultancy; Sangamo: Consultancy, Honoraria. Voskaridou:Acceleron: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene Corp: Membership on an entity's Board of Directors or advisory committees, Research Funding. Forni:Novartis: Research Funding; Roche: Research Funding; Celgene: Research Funding. Perrotta:Acceleron Pharma: Research Funding; Novartis: Research Funding. Lal:Celgene Corporation: Research Funding; Bluebird Bio: Research Funding; La Jolla Pharmaceutical Company: Consultancy, Research Funding; Insight Magnetics: Research Funding; Novartis: Research Funding; Terumo Corporation: Research Funding. Kattamis:ApoPharma: Honoraria; Vifor Pharma: Consultancy; CELGENE: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Vlachaki:Novartis: Honoraria. Origa:Cerus Corporation: Research Funding; Bluebird Bio: Consultancy; Novartis: Honoraria; Apopharma: Honoraria. Aydinok:TERUMO: Research Funding; Protagonist: Other: SSC; CRISPR Tech: Other: DMC; Cerus: Honoraria, Research Funding; La Jolla Pharmaceuticals: Research Funding; Novartis: Research Funding, Speakers Bureau; Celgene: Research Funding. Ho:Takeda: Honoraria, Other: travel to meeting; Novartis: Honoraria; Janssen: Honoraria; Amgen: Honoraria; Celgene: Other: Travel to meeting. Chew:Celgene: Research Funding. Tantiworawit:Celgene: Honoraria, Research Funding, Speakers Bureau. Shah:Novartis: Honoraria, Speakers Bureau; Sobi/Apotex: Honoraria; Celgene Corp: Other: Steering committee; Roche: Other: Advisory board meeting. Neufeld:Celgene Corp.: Consultancy, Other: Steering committee; Acceleron Pharma: Consultancy. Laadem:Celgene: Employment, Equity Ownership. Shetty:Celgene: Employment, Equity Ownership. Zou:Celgene Corporation: Employment, Equity Ownership. Miteva:Celgene Corporation: Employment, Other: grants. Zinger:Celgene Corporation: Employment. Linde:AbbVie: Equity Ownership; Abbott Laboratories: Equity Ownership; Fibrogen: Equity Ownership; Acceleron Pharma: Employment, Equity Ownership. Sherman:Acceleron Pharma: Employment, Equity Ownership. Hermine:AB Science: Consultancy, Equity Ownership, Honoraria, Research Funding; Celgene Corporation: Research Funding; Hybrigenics: Research Funding; Erythec: Research Funding; Novartis: Research Funding. Porter:Cerus: Honoraria; Agios: Honoraria; Novartis: Consultancy. Piga:La Jolla: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bluebird Bio: Honoraria; Apopharma: Honoraria, Research Funding; Celgene Corp: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Acceleron: Research Funding.

Limited data regarding methemoglobinemia in pregnancy, particularly secondary to dapsone is available up to date. We report a case of dapsone-induced methemoglobinemia in a pregnant mother with multibacillary leprosy who presented with fever, productive cough and cyanosis of 2 days duration 2 weeks after multidrug therapy was commenced. On examination, she had central cyanosis with low oxygen saturation (SpO2 = 84–88%). Arterial blood gas analysis showed PO2 of 111 mmHg and SO2 of 98 mmHg. Patient was administered 100% oxygen inhalation, but there was no improvement in cyanosis. Vitamin C (1000 mg/day) was prescribed. Dapsone was replaced by ofloxacin 200 mg twice daily. There was a gradual increase in SpO2 level. She delivered a healthy baby. In conclusion, clinicians should be aware of the side effects of dapsone and know how to promptly manage any undesirable events. Ofloxacin is a safe and feasible alternative in replacement of dapsone in pregnancy.

Haemoglobin (Hb) Cheverly is a rare, low oxygen affinity haemoglobinopathy. It is a result of point mutation at the 45 codon of the beta globin genes that leads to substitution of phenylalanine by serine. It is characterised by spuriously low peripheral oxygen saturation with normal arterial oxygen saturation. We describe a family of three with Hb Cheverly in Sarawak General Hospital, Malaysia. It was discovered through incidental finding during hospital admission for unrelated complaints. Laboratory testing revealed abnormal haemoglobin detected at the C window of the high performance liquid chromatography. Subsequent DNA analysis detected replacement of thymidine by cytosine at the beta globin genes. Hb Cheverly may or may not have clinical significance as most of the patients live a normal life; however, it is crucial for us to make early diagnosis to prevent unnecessary extensive investigations for hypoxaemia detected via pulse oximetry, especially in the midst of COVID-19 pandemic.

Background. Polycythemia (PV) patients with hematocrit above 45% are at increased risk of thrombotic complications and are treated with phlebotomy and/or cytoreductive therapy to reach a hematocrit target below 45%. Rusfertide (PTG-300) is a peptidic mimetic of hepcidin that is being developed for treatment of polycythemia vera (PV). A Phase 2 trial has indicated that rusfertide is effective at reducing the number of phlebotomies and maintaining hematocrit below 45% without phlebotomy in PV patients who are either high-risk or low-risk, patients treated with cytoreductive therapy (hydroxyurea, interferon, ruxolitinib) and patients treated with phlebotomy alone (Kremyanskaya, ASH 2020). The current trial (PTG-300-08) tested the ability of rusfertide to normalize hematocrit in PV patients with elevated hematocrit without instituting phlebotomy treatment to normalize hematocrit to below 45% in PV patients without requiring phlebotomy and/or cytoreductive treatment. Methods. Eligible study subjects were diagnosed with PV (in accordance with the WHO 2016 criteria), had baseline hematocrit above 48%, and a history of 3 or more hematocrit values above 48% in the year prior to enrollment. High-risk and low-risk subjects treated with phlebotomy alone or with concurrent cytoreductive therapy were eligible. Rusfertide was added on to each subject's current therapy. The initial rusfertide dose was 40 mg administered subcutaneously twice weekly. When each subject's hematocrit was below 45%, the dosing schedule was changed to weekly and the rusfertide dose was adjusted to maintain hematocrit below 45%. Results. Sixteen subjects (12 male and 4 females) have been enrolled. The mean age is 56.1 years; the mean time since diagnosis is 3.74 years; 10 subjects are low risk PV; 12 subjects are receiving concurrent hydroxyurea and 4 subjects were not receiving cytoreductive therapy. Baseline values (mean, min-max) HCT (51.0%, 47.4 - 59), WBC (12,338/µL, 7,000 - 24,600), RBCs (5.9x10 6/µL, 4.3 - 7.6), platelets (486,500/µL, 242,000 - 904,000). All subjects had rapid decreases in hematocrit to below 45% without the use of phlebotomy (Figure 1a). Hematocrit levels remained well controlled after falling below 45% as investigators reduced rusfertide dose to maintenance once weekly regimen. Hemoglobin (Figure 1b) fell rapidly. Erythrocyte counts (Figure 1c) also fell rapidly, indicating that decreased hematocrit is due to decreased erythrocytosis. For the 11 subjects with adequate follow-up, the mean rate of absolute hematocrit decrease was 1.76% per week (median: 1.81%/week; min - max: 0.65 - 2.69%) and the mean time to reach goal hematocrit below 45% was 4.79 weeks (median: 4.14 weeks, min - max: 3.57 - 8.14). Eight subjects reported adverse events (AEs). Injection site reactions (ISRs) occurred in 7 subjects and were mild or moderate in severity. The most common ISRs were erythema (n=7), induration (n=5) and pruritis (n=2). Adverse events other than ISRs that occurred in 2 or more subjects were hypertension (n=2), pyrexia (n=2) and thrombocytosis (n=2). There were two serious adverse events (worsening migraine and pleuritic chest pain) and both were considered unrelated to rusfertide. Overall, rusfertide was well tolerated. Conclusions. This study demonstrates that induction therapy with twice weekly rusfertide administration was effective in rapidly achieving target hematocrit below 45% without phlebotomy in all PV patients which was then successfully maintained with weekly rusfertide treatment. Moreover, the twice weekly injections of rusfertide used to rapidly lower hematocrit levels were safe and well tolerated. Key words: Hepcidin, Hematocrit, Rusfertide, PTG-300, Polycythemia Vera, PV, Therapeutic Phlebotomy Figure 1 Figure 1. Disclosures Gupta: Protagonist Therapeutics: Current Employment. Valone: Protagonist Therapeutics: Consultancy, Current equity holder in publicly-traded company. Khanna: Protagonist: Current Employment, Current equity holder in publicly-traded company. Modi: Protagonist Therapeutics: Current Employment. Hoffman: Kartos Therapeutics, Inc.: Research Funding; Protagonist Therapeutics, Inc.: Consultancy; Novartis: Other: Data Safety Monitoring Board, Research Funding; AbbVie Inc.: Other: Data Safety Monitoring Board, Research Funding.