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.).

Homozygous SPTA1-associated hereditary pyropoikilocytosis presenting as hydrops fetalis.

INTRODUCTION: Hereditary pyropoikilocytosis (HPP) is a heterogeneous inherited disorder of red blood cell (RBC) membrane and cytoskeletal proteins that leads to hemolytic anemia. HPP is characterized by marked poikilocytosis, microspherocytes, RBC fragmentation, and elliptocytes on peripheral blood smear. Mutations in SPTA1 can cause HPP due to a quantitative defect in α-spectrin and can lead to profound fetal anemia and nonimmune hydrops fetalis, which can be managed with intrauterine transfusion. CASE PRESENTATION: We present a case of a 26-year-old G4P2102 woman of Amish-Mennonite ancestry with a pregnancy complicated by fetal homozygosity for an SPTA1 gene variant (SPTA1c.6154delG) as well as severe fetal anemia and hydrops fetalis, which was managed with four intrauterine transfusions between 26 and 30 weeks gestation. Pre-transfusion peripheral smears from fetal blood samples showed RBC morphology consistent with HPP. The neonate had severe hyperbilirubinemia at birth, which has resolved, but remains transfusion-dependent at 6 months of life. DISCUSSION/CONCLUSION: To our knowledge, this is the first report that correlates homozygosity of the SPTA1c.6154delG gene variant with RBC dysmorphology and establishes the diagnosis of HPP.

CD59 gene: 143 haplotypes of 22,718 nucleotides length by computational phasing in 113 individuals from different ethnicities.

BACKGROUND: CD59 deficiency due to rare germline variants in the CD59 gene causes disabilities, ischemic strokes, neuropathy, and hemolysis. CD59 deficiency due to common somatic variants in the PIG-A gene in hematopoietic stem cells causes paroxysmal nocturnal hemoglobinuria. The ISBT database lists one nonsense and three missense germline variants that are associated with the CD59-null phenotype. To analyze the genetic diversity of the CD59 gene, we determined long-range CD59 haplotypes among individuals from different ethnicities. METHODS: We determined a 22.7 kb genomic fragment of the CD59 gene in 113 individuals using next-generation sequencing (NGS), which covered the whole NM_203330.2 mRNA transcript of 7796 base pairs. Samples came from an FDA reference repository and our Ethiopia study cohorts. The raw genotype data were computationally phased into individual haplotype sequences. RESULTS: Nucleotide sequencing of the CD59 gene of 226 chromosomes identified 216 positions with single nucleotide variants. Only three haplotypes were observed in homozygous form, which allowed us to assign them unambiguously as experimentally verified CD59 haplotypes. They were also the most frequent haplotypes among both cohorts. An additional 140 haplotypes were imputed computationally. DISCUSSION: We provided a large set of haplotypes and proposed three verified long-range CD59 reference sequences, based on a population approach, using a generalizable rationale for our choice. Correct long-range haplotypes are useful as template sequences for allele calling in high-throughput NGS and precision medicine approaches, thus enhancing the reliability of clinical diagnostics. Long-range haplotypes can also be used to evaluate the influence of genetic variation on the risk of transfusion reactions or diseases.

Infantile pyknocytosis, a neonatal hemolytic anemia with Heinz bodies: A cohort study.

Infantile pyknocytosis (IP) is a rare, probably misestimated, cause of non-immune neonatal hemolytic anemia evolving in two phases: an initial phase with severe jaundice, followed by a second phase with hemolytic anemia, which may require neonatal intensive care. The diagnosis of IP is based on the transient presence on blood smear of hyperdense, contracted, and/or spiculated red blood cells (pyknocytes), associated with the spontaneous resolution of clinico-biological features and the exclusion of other causes. If the etiology remains undetermined, some contributing factors, such as oxidative stress, have been proposed. We report the description of 16 patients with IP aiming at clarifying the circumstances associated with the development of this acquired disorder. In the acute phase, the mean hemoglobin nadir and pyknocyte count were 7.8 g/dL and 11%, respectively, and strikingly, Heinz bodies were evident in 50% of the newborns, but in 100% after prolonged incubation (4 hours). A high proportion of Mediterranean or African ancestry was noted in newborns, as well as a significant number of peripartum events, such as respiratory distress. If the etiology of IP is certainly multifactorial, our series reinforces the role of oxidative stress, which may, at least in part, find origin in desaturation episodes in newborns.

The meaning of non-criteria clinical manifestations in a real-life primary antiphospholipid syndrome cohort.

OBJECTIVES: We aimed to evaluate the prevalence of non-criteria clinical features in patients with primary antiphospholipid syndrome (APS), and to assess their relationship to thrombosis and damage. METHODS: We retrospectively included 177 primary APS patients, and/or patients who only achieved the serological Sydney criteria but had thrombocytopenia and/or haemolytic anaemia. We registered demographics, serology, treatment, thrombotic/obstetric manifestations and non-criteria clinical manifestations (cutaneous, haematologic, renal, heart valve disease, and neurological). We scored the DIAPS and a modified SLICC index. We used logistic regression and reported OR with 95% CI. RESULTS: 78% were women with a median follow-up of 6.7 years. Thrombosis was found in 74% of patients, 29.3% had obstetric features, and 64% had non-criteria clinical manifestations. The frequency of the non-criteria clinical manifestation was: haematologic 40.1%, cutaneous 20.9%, neurologic 18%, cardiac 5% and renal 4.5%. Non-criteria features were associated with LA (OR 2.3, 95% 1.03-5.1) and prednisone use (OR 8.2, 95% CI 1.7-39.3). A DIAPS score ≥1 was associated with thrombosis (OR 53.1, 95% CI 17.8-15.2), prednisone use (OR 0.27, CI 95% 0.09-0.83) and neurological involvement (OR 6.4, 95% CI 1.05-39.8); whereas a modified SLICC ≥ 1 with thrombosis (OR 10.2; IC 95% 4.43-26.1), neurological involvement (OR 6.4, 95%CI 1.05-39.8), obstetric features (OR 0.32 CI 95% 0.12-0,81) and cutaneous features (OR 5.3, CI 95% 1.4-19), especially livedo reticularis (OR 5.45; IC 95% 1.49-19.8). CONCLUSIONS: Non-criteria clinical manifestations are common and associated with LA. Among them, neurologic involvement and the presence of livedo were associated with damage accrual.

A Real-World Disproportionality Analysis of Drug-Induced Immune Hemolytic Anemia in the FDA Adverse Event Reporting System.

BACKGROUND: Drug-induced immune hemolytic anemia (DIIHA) is a rare but potentially life-threatening pharmacogenic hematological adverse effect. Updating the risk of DIIHA among the currently available drugs based on spontaneously reported adverse event data is of great significance. OBJECTIVE: This study aimed to identify the top 50 drugs associated with immune hemolytic anemia in adults as well as common drugs that could cause immune hemolytic anemia in children based on the United States Food and Drug Administration Adverse Event Reporting System (FAERS) database. METHODS: We extracted adverse events (AE) in the FAERS database from Q1 2004 to Q3 2022 using Open vigil2.1. We use the high-level term "anaemias haemolytic immune" according to the Medical Dictionary for Regulatory Activities (MedDRA) Dictionary (version 24.0). The reported correlation between drugs and DIIHA risk was identified by reported odds ratio (ROR) and proportional reporting ratio (PRR). RESULTS: There were 10500309 AEs in FAERS from 2004Q1 to 2022Q3, of which 2326 (0.02%) were DIIHA cases. The incidence of DIIHA is comparable between males and females. The most common drugs associated with DIIHA in adults and children are summarized according to the number of AE reports. The top 3 categories in terms of quantity of drugs are antineoplastic agents, immunosuppressants, and antibiotics for systemic use. The top 5 drugs in terms of ROR and PRR are alemtuzumab, daclizumab, fludarabine, busulfan, and bendamustine in adults, with entecavir, treosulfan, vinorelbine, pegademase, and alemtuzumab for children. CONCLUSIONS: Our study identified the most common drugs that could induce DIIHA in adults and children, as well as the respective ROR and PRR value to discover new drug signals. This study provides references to clinicians for the management of rare DIIHA.

Hemolytic anemia associated with intravenous immunoglobulin in Kawasaki disease.

BACKGROUND: The administration of high-dose intravenous immunoglobulin (IVIG) is a standard treatment for the management of Kawasaki disease (KD). IVIG is known to be a highly effective and safe treatment. CASE PRESENTATION: We report the development of hemolytic anemia in seven children receiving repeated doses of IVIG. The children were aged 3-44 months and included 4 girls and 3 boys. All children received 10% IVIG and a second course of immunoglobulin because they did not respond to the first course of immunoglobulin. Two received high-dose aspirin (50 mg/kg), and five received low-dose aspirin (5 mg/kg). Two patients required additional methylprednisolone pulse therapy (30 mg/kg) after the second dose of immunoglobulin, and three patients received oral prednisolone therapy for defervescence. Three patients showed coronary artery dilation during hospitalization and normalized within two months. Pretreatment hemoglobin averaged 11.3-14.2 g/dL, and post-hemolytic anemia hemoglobin ranged from 7.4 to 9.6 g/dL, with a difference of 1.7-6.8 g/dL. Reticulocytes were increased to 3.3-13.2%. Peripheral blood smears showed normochromic normocytic anemia, and anisopoikilocytosis. All children were positive for warm-type antibodies with IgG+, C3d- in direct antiglobulin test, and the blood group was A + in five and B + in two. None of the patients received immunomodulatory therapy or red blood cell transfusions. They were followed for a year and all recovered. CONCLUSION: Especially, in non-O blood group KD patients who are refractory to initial IVIG and require a second dose of IVIG or 10% formulation the possibility of immune hemolytic anemia should be carefully considered, and close follow-up should be maintained after therapy.

Tyrosine kinase inhibitor-induced immune hemolytic anemia; three different drugs in three separate cases.

INTRODUCTION: Molecular multitargeted small tyrosine kinase inhibitory (TKI) agents such as axitinib, sunitinib and pazopanib are commonly used in several types of solid tumors. Anemia is not a rare effect of these drugs which may occur at all grades. However, drug-induced immune hemolytic anemia (IHA), a very rare condition is distinctive from other types of anemia with its specific mechanism and management strategy. CASE REPORTS: We reported three different TKI-induced IHA cases that occurred due to axitinib, sunitinib, and pazopanib, respectively. The first two cases were diagnosed with renal cell carcinoma and the last one was diagnosed with soft tissue sarcoma. They all presented with the characteristic symptoms of anemia and hemolysis. All the cases were detected positive for the complement C3d direct antiglobulin (direct coombs) test. MANAGEMENT AND OUTCOMES: Discontinuation of the causative drug and 1 mg/kg/day dose of corticosteroid treatment were able to control IHA in all three cases. Excluding the other factors of IHA and an evident laboratory and clinical benefit after withholding the TKI led to the diagnosis of TKI-related IHA in each case. DISCUSSION: TKIs are relatively new in clinical practice and are being used for more indications and in more patients. To our knowledge#these three cases are unique in terms of axitinib#sunitinib#and pazopanib-related IHA.

Complement C5 inhibition protects against hemolytic anemia and acute kidney injury in anthrax peptidoglycan-induced sepsis in baboons.

Late-stage anthrax infections are characterized by dysregulated immune responses and hematogenous spread of Bacillus anthracis, leading to extreme bacteremia, sepsis, multiple organ failure, and, ultimately, death. Despite the bacterium being nonhemolytic, some fulminant anthrax patients develop a secondary atypical hemolytic uremic syndrome (aHUS) through unknown mechanisms. We recapitulated the pathology in baboons challenged with cell wall peptidoglycan (PGN), a polymeric, pathogen-associated molecular pattern responsible for the hemostatic dysregulation in anthrax sepsis. Similar to aHUS anthrax patients, PGN induces an initial hematocrit elevation followed by progressive hemolytic anemia and associated renal failure. Etiologically, PGN induces erythrolysis through direct excessive activation of all three complement pathways. Blunting terminal complement activation with a C5 neutralizing peptide prevented the progressive deposition of membrane attack complexes on red blood cells (RBC) and subsequent intravascular hemolysis, heme cytotoxicity, and acute kidney injury. Importantly, C5 neutralization did not prevent immune recognition of PGN and shifted the systemic inflammatory responses, consistent with improved survival in sepsis. Whereas PGN-induced hemostatic dysregulation was unchanged, C5 inhibition augmented fibrinolysis and improved the thromboischemic resolution. Overall, our study identifies PGN-driven complement activation as the pathologic mechanism underlying hemolytic anemia in anthrax and likely other gram-positive infections in which PGN is abundantly represented. Neutralization of terminal complement reactions reduces the hemolytic uremic pathology induced by PGN and could alleviate heme cytotoxicity and its associated kidney failure in gram-positive infections.

[The 507th case: hemolytic anemia, parvovirus B19, and multiple organ dysfunction].

A 19-year-old male patient with high-risk acute B-cell lymphoblastic leukemia received haploidentical stem cell transplantation. He developed anemia repeatedly and parvovirus B19 nucleic acid was positive in blood plasma. The patient was diagnosed with cold agglutinin syndrome and multiple organ dysfunction including respiratory failure and hepatitis. In the conflict between viral infection and the treatment of cold agglutinin syndrome, we provided supportive treatment, complement inhibitors to control hemolysis, and antiviral therapy. After timely glucocorticoid and immunosuppressant therapy, the patient had achieved a good response.

[A Successful Surgical Treatment of Hemolytic Anemia Caused by Aortic Valve Perivalvular Leakage and Severely Kinked Elephant Trunk:Report of a Case].

Both perivalvular leakage and kinked prosthetic graft may cause hemolysis. A 72-year-old man was refereed to our hospital because of hemolytic anemia. He has past histories of total aortic arch replacement and repeat aortic valve replacement for aortic aneurysm and prosthetic valve endocarditis. Pre-operative examinations demonstrated aortic valve perivalvular leakage and severe graft kinking of the elephant trunk. Repeat aortic valve replacement and axillo-femoral bypass were performed successfully. Hemolysis got better after the operation and the patient discharged home in stable condition.

Heterozygosity for bisphosphoglycerate mutase deficiency expressing clinically as congenital erythrocytosis: A case series and literature review.

Erythrocytosis is associated with increased red blood cell mass and can be either congenital or acquired. Congenital secondary causes are rare and include germline variants increasing haemoglobin (Hb)-oxygen affinity (e.g., Hb or bisphosphoglycerate mutase (BPGM) variants) or affecting oxygen-sensing pathway proteins. Here, we describe five adults from three kindreds with erythrocytosis associated with heterozygosity for BPGM variants, including one novel. Functional analyses showed partial BPGM deficiency, reduced 2,3-bisphosphoglycerate levels and/or increased Hb-oxygen affinity. We also review currently known BPGM variants. This study contributes to raising awareness of BPGM variants, and in particular that heterozygosity for BPGM deficiency may already manifest clinically.

A British Society for Haematology Guideline: Diagnosis and management of thrombotic thrombocytopenic purpura and thrombotic microangiopathies.

The objective of this guideline is to provide healthcare professionals with clear, up-to-date and practical guidance on the management of thrombotic thrombocytopenic purpura (TTP) and related thrombotic microangiopathies (TMAs), including complement-mediated haemolytic uraemic syndrome (CM HUS); these are defined by thrombocytopenia, microangiopathic haemolytic anaemia (MAHA) and small vessel thrombosis. Within England, all TTP cases should be managed within designated regional centres as per NHSE commissioning for highly specialised services.

The cation-leaky hereditary stomatocytosis syndromes: A tale of six proteins.

This review concerns a series of dominantly inherited haemolytic anaemias in which the membrane of the erythrocyte 'leaks' the univalent cations, compromising the osmotic stability of the cell. The majority of the conditions are explained by mutations in one of six genes, coding for multispanning membrane proteins of different structure and function. These are: RhAG, coding for an ammonium carrier; SLC4A1, coding for the band 3 anion exchanger; PIEZO1, coding for a mechanosensitive cation channel; GLUT1, coding for a glucose transporter; KCNN4, coding for an internal-calcium-activated potassium channel; and ABCB6, coding for a porphyrin transporter. This review describes the five clinical syndromes associated with genetic defects in these genes and their variable genotype/phenotype relationships.

Thrombosis in Pregnant Women with Hemolytic Anemia.

Hemolytic anemias are a group of uncommon disorders affecting both genders, frequently occurring at the reproductive age. While a link between hemolysis and hypercoagulability has been suggested based on the elucidation of certain involved pathophysiological mechanisms, the extent of thrombotic risk in pregnant women with hemolytic anemia remains debatable. Due to the paucity of pregnancy-related data, risk assessment of gestations in women with hemolytic anemia is complicated. This review will highlight the latest advances in the diagnosis and management of these challenging disorders in pregnancy.

Renal Thrombotic Microangiopathy: A Review.

Thrombotic microangiopathy (TMA), a pathological lesion observed in a wide spectrum of diseases, is triggered by endothelial injury and/or dysfunction. Although TMA lesions are often accompanied by clinical features of microangiopathic hemolytic anemia, thrombocytopenia, and ischemic end-organ injury, renal-limited forms of TMA are not infrequently encountered in clinical practice. The presence of renal-limited manifestations can be diagnostically challenging, often delaying the initiation of targeted therapy. Prompt investigation and empirical treatment of TMA is warranted to reduce associated morbidity and mortality. Major advances have been made with respect to the pathophysiology of primary TMA entities, with the subsequent development of novel diagnostic tools and lifesaving therapies for diseases like thrombotic thrombocytopenic purpura and complement-mediated TMA. This article will review the clinical presentation and pathologic hallmarks of TMA involving the kidney, and the disease-specific mechanisms that contribute to the endothelial injury that characterizes TMA lesions. Diagnostic approach and both empirical and disease-specific treatment strategies will be discussed, along with the potential role for emerging targeted disease-specific therapies.

How I treat microangiopathic hemolytic anemia in patients with cancer.

Microangiopathic hemolytic anemia (MAHA) with thrombocytopenia, suggests a thrombotic microangiopathy (TMA), linked with thrombus formation affecting small or larger vessels. In cancer patients, it may be directly related to the underlying malignancy (initial presentation or progressive disease), to its treatment, or a separate incidental diagnosis. It is vital to differentiate incidental thrombotic thrombocytopenia purpura or atypical hemolytic uremic syndrome in cancer patients presenting with a TMA, as they have different treatment strategies, and prompt initiation of treatment impacts outcome. In the oncology patient, widespread microvascular metastases or extensive bone marrow involvement can cause MAHA and thrombocytopenia. A disseminated intravascular coagulation (DIC) picture may be precipitated by sepsis or driven by the cancer itself. Cancer therapies may cause a TMA, either dose-dependent toxicity, or an idiosyncratic immune-mediated reaction due to drug-dependent antibodies. Many causes of TMA seen in the oncology patient do not respond to plasma exchange and, where feasible, treatment of the underlying malignancy is important in controlling both cancer-TMA or DIC driven disease. Drug-induced TMA should be considered and any putative causal agent stopped. We will discuss the differential diagnosis and treatment of MAHA in patients with cancer using clinical cases to highlight management principles.

Passive transfer of alloantibodies through breast milk as a mediator of hemolytic anemia.

BACKGROUND: Hemolytic disease of the fetus and newborn (HDFN) is characterized by destruction of fetal/neonatal red blood cells (RBCs) secondary to maternally derived antibodies, which are typically thought to be passively acquired via placental transfer. Few cases have examined the possibility of HDFN mediated by maternal antibodies passively transferred via breast milk. METHODS: We describe two cases of persistent HDFN in infants potentially mediated by passively acquired antibodies via maternal breast milk. We discuss supporting and refuting evidence that may account for this possibility and describe testing methodology illustrating how maternal alloantibodies can be detected in breast milk. RESULTS: In both cases, anti-D antibodies were detected in maternal breast milk. One patient experienced a significant decrease in anti-D plasma titer from 64 to 4 dilutions following 2 weeks of breastfeeding cessation. The other patient experienced a resolution of anemia without breastfeeding cessation. CONCLUSION: There is a paucity of data regarding the lifespan of passively acquired RBC antibodies in neonatal circulation, with significant variation noted between passively acquired IgG based on studies utilizing intravenous immunoglobulin compared to studies of maternally-acquired antiviral IgG antibodies. While our data do not definitively implicate passive transfer of alloantibodies in breast milk as a mediator of HDFN, they do illustrate the need for further investigation into the mechanisms and kinetics of passively acquired antibodies in neonatal circulation.

Targeted next-generation sequencing identifies eighteen novel mutations expanding the molecular and clinical spectrum of PKLR gene disorders in the Indian population.

Pyruvate kinase deficiency (PKD) is an autosomal recessive condition, caused due to homozygous or compound heterozygous mutation in the PKLR gene resulting in non-spherocytic hereditary hemolytic anemia. Clinical manifestations in PKD patients vary from moderate to severe lifelong hemolytic anemia either requiring neonatal exchange transfusion or blood transfusion support. Measuring PK enzyme activity is the gold standard approach for diagnosis but residual activity must be related to the increased reticulocyte count. The confirmatory diagnosis is provided by PKLR gene sequencing by conventional as well as targeted next-generation sequencing involving genes associated with enzymopathies, membranopathies, hemoglobinopathies, and bone marrow failure disorders. In this study, we report the mutational landscape of 45 unrelated PK deficiency cases from India. The genetic sequencing of PKLR revealed 40 variants comprising 34 Missense Mutations (MM), 2 Nonsense Mutations (NM), 1 Splice site, 1 Intronic, 1 Insertion, and 1 Large Base Deletion. The 17 novel variants identified in this study are A115E, R116P, A423G, K313I, E315G, E318K, L327P, M377L, A423E, R449G, H507Q, E538K, G563S, c.507 + 1 G > C, c.801_802 ins A (p.Asp268ArgfsTer48), IVS9dsA-T + 3, and one large base deletion. In combination with previous reports on PK deficiency, we suggest c.880G > A, c.943G > A, c.994G > A, c.1456C > T, c.1529G > A are the most frequently observed mutations in India. This study expands the phenotypic and molecular spectrum of PKLR gene disorders and also emphasizes the importance of combining both targeted next-generation sequencing with bioinformatics analysis and detailed clinical evaluation to elaborate a more accurate diagnosis and correct diagnosis for transfusion dependant hemolytic anemia in a cohort of the Indian population.

Sutimlimab provides clinically meaningful improvements in patient-reported outcomes in patients with cold agglutinin disease: Results from the randomised, placebo-controlled, Phase 3 CADENZA study.

Cold agglutinin disease (CAD) is a rare chronic autoimmune haemolytic anaemia, driven mainly by classical complement pathway activation, leading to profound fatigue and poor quality of life. In the Phase 3 CADENZA trial, sutimlimab-a C1s complement inhibitor-rapidly halted haemolysis, increased haemoglobin levels and improved fatigue versus placebo in patients with CAD without a recent history of transfusion. Patient-reported outcomes (PROs) included Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue), 12-Item Short Form Health Survey (SF-12), EuroQol visual analogue scale (EQ-VAS), Patient Global Impression of Change (PGIC) and Patient Global Impression of (fatigue) Severity (PGIS). Sutimlimab resulted in significant rapid and meaningful improvements versus placebo in PROs. From Week 1, the FACIT-Fatigue mean score increased >5 points above baseline (considered a clinically important change [CIC]). Least-squares (LS) mean change in FACIT-Fatigue score from baseline to treatment assessment timepoint was 10.8 vs. 1.9 points (sutimlimab vs. placebo; p < 0.001). Improvements in physical (PCS) and mental (MCS) component scores of the SF-12 were also considered CICs (LS mean changes from baseline to Week 26: PCS 5.54 vs. 1.57 [p = 0.064]; MCS 5.65 vs. -0.48 [p = 0.065]). These findings demonstrate that in addition to improving haematologic parameters, sutimlimab treatment demonstrates significant patient-reported benefits. Study registered at www.clinicaltrials.gov: NCT03347422.