Complement Mediated Hemolytic Anemias in the COVID-19 Era: Case Series and Review of the Literature

The complex pathophysiologic interplay between SARS-CoV-2 infection and complement activation is the subject of active investigation. It is clinically mirrored by the occurrence of exacerbations of complement mediated diseases during COVID-19 infection. These include complement-mediated hemolytic anemias such as paroxysmal nocturnal hemoglobinuria (PNH), autoimmune hemolytic anemia (AIHA), particularly cold agglutinin disease (CAD), and hemolytic uremic syndrome (HUS). All these conditions may benefit from complement inhibitors that are also under study for COVID-19 disease. Hemolytic exacerbations in these conditions may occur upon several triggers including infections and vaccines and may require transfusions, treatment with complement inhibitors and/or immunosuppressors (i.e., steroids and rituximab for AIHA), and result in thrombotic complications. In this manuscript we describe four patients (2 with PNH and 2 with CAD) who experienced hemolytic flares after either COVID-19 infection or SARS-Cov2 vaccine and provide a review of the most recent literature. We report that most episodes occurred within the first 10 days after COVID-19 infection/vaccination and suggest laboratory monitoring (Hb and LDH levels) in that period. Moreover, in our experience and in the literature, hemolytic exacerbations occurring during COVID-19 infection were more severe, required greater therapeutic intervention, and carried more complications including fatalities, as compared to those developing after SARS-CoV-2 vaccine, suggesting the importance of vaccinating this patient population. Patient education remains pivotal to promptly recognize signs/symptoms of hemolytic flares and to refer to medical attention. Treatment choice should be based on the severity of the hemolytic exacerbation as well as of that of COVID-19 infection. Therapies include transfusions, complement inhibitor initiation/additional dose in the case of PNH, steroids/rituximab in patients with CAD and warm type AIHA, plasma exchange, hemodialysis and complement inhibitor in the case of atypical HUS. Finally, anti-thrombotic prophylaxis should be always considered in these settings, provided safe platelet counts.

Clinically Important Change in SF-12v2 Physical (PCS) and Mental (MCS) Component Summary Scores for Patients with Cold Agglutinin Disease: An Analysis Using the Phase 3 CARDINAL and CADENZA Studies

Introduction Cold Agglutinin Disease (CAD) is an autoimmune condition resulting in hemolytic anemia; the subsequent fatigue causes a reduction in patient's physical and mental health-related quality of life (HRQoL). Sutimlimab (formerly BIVV009) is a humanized monoclonal anti-C1s antibody with a clinical trial program to support its development as a treatment for CAD. CARDINAL (NCT03347396) and CADENZA (NCT03347422) are Phase 3 clinical trials that assessed the treatment-related change in HRQoL using the 12-item Short-Form Health Survey (version 2) (SF-12v2) in patients with CAD treated with sutimlimab. This analysis aimed to estimate the clinically important change (CIC) in SF-12v2 physical (PCS) and mental (MCS) component summary scores, using pooled data from CARDINAL and CADENZA. Methods CARDINAL was an open-label, single-arm, multicenter study for patients with CAD with a recent blood transfusion. CADENZA was a randomized, double-blind, placebo-controlled, multicenter study; patients with CAD (without a recent blood transfusion) were randomized 1:1 to receive sutimlimab or placebo. In both studies, patients underwent efficacy and safety assessments for 6 months (Part A). Data from the Part A 26-week component of both studies were combined for these analyses. CIC, defined as mean score change divided by SD at baseline, gave treatment effect sizes of 0.2 (small), 0.5 (moderate) or 0.8 (large), allowing for interpretation of patient-reported outcomes by pre-determining clinically meaningful improvements in physical and mental well-being. Anchor- and distribution-based analyses were performed to estimate the CIC for the following patient-reported outcome measures: Patient Global Impression of (fatigue) Severity (PGIS) and Patient Global Impression of Change (PGIC). Anchor-based approaches (mean change and model-based) examined the relationship between change in SF-12v2 PCS and MCS scores and change in related anchor variables: change in PGIS, PGIC (from baseline to Week 26) and hemoglobin levels (g/dl) (from baseline to the mean value of Weeks 23, 25 and 26). The independent variable was change in PCS and MCS scores and dependent variables were binary (improvement vs. no improvement) in model-based analyses. Results Fifty-five patients with SF-12v2 data available were included from CARDINAL (n=17) and CADENZA (n=38). The median (range) age was 70 (46-88) years and 76% of patients were female (n=42). Mean (SD) PCS and MCS scores at baseline were 40.9 (7.8) and 47.3 (9.1), respectively. From baseline to Week 26, mean (SD) changes in PCS and MCS scores were 4.1 (7.1) and 3.1 (11.6), respectively. Correlations between changes in PCS and MCS scores and PGIS, hemoglobin, and self-report of change in PGIC at Week 26 ranged from 0.36 to 0.55, indicating moderate associations (Table 1). When using an anchor-based approach that evaluated mean change in PCS and MCS scores, CIC estimates ranged from 2.9 to 7.4 for PCS and 2.2 to 7.0 for MCS (Table 2). Results from the 2 model-based anchor approaches, which estimated CIC using receiver operating characteristic curves and an adjusted logistic regression-based approach ranged from 2.0 to 7.3 for PCS and 1.1 to 4.1 for MCS (Table 2). Distribution-based analyses determined the CIC to be 3.9 and 4.6 for PCS and MCS, respectively, when based on one-half of the standard deviation of baseline scores, and 3.5 (PCS) and 4.1 (MCS) when based on the standard error of measurement. The median estimate produced by all anchor-based methods were closely aligned with results of distribution-based analyses. Therefore, taking into consideration all approaches, the median CICs for CAD patients for PCS and MCS were 3.9 and 2.8, respectively. Conclusion In this analysis, patients with CAD had median CIC values of 3.9 and 2.8 for PCS and MCS, respectively. In a previous study, anchor-based analyses for the general population gave CIC scores of 3.0 for both PCS and MCS (Maruish ME et al. 3 rd edition; Lincoln, RI; 2012). The results of this study converge well with those estimates observed for the general population involving thousands of observations. This analysis also demonstrated that meaningful physical and mental health benefits (including a reduction in fatigue) were associated with improvements in hemoglobin levels, a main clinical outcome measure of CAD. Figure 1 Figure 1. Disclosures Joly: Sanofi: Current Employment. Kosinski: QualityMetric Incorporated, LLC: Current Employment. Shafer: Sanofi: Current Employment, Current equity holder in publicly-traded company; Pfizer: Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months, Ended employment in the past 24 months. Wardecki: Sanofi: Current Employment, Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months, Other: May hold shares and/or stock options with Sanofi. Karaouni: BMAPS SARL(Geneva, Switzerland): Current Employment; Sanofi: Consultancy. Hill: Amgen: Honoraria; Alexion: Honoraria; ReAlta: Consultancy; Sanofi: Consultancy; Grifols: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Argenx: Consultancy; Apellis: Consultancy, Honoraria.

Development of a Cold Agglutinin Disease-Specific Patient-Reported Outcome Symptom Measure

Introduction Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia in which red blood cells are bound by cold agglutinin autoantibodies. In addition to cold-induced symptoms, patients with CAD experience symptoms of chronic anemia and hemolysis including fatigue, weakness, and shortness of breath (Swiecicki PL et al. Blood 2013;122(7):1114-21). The objectives of this study were to identify disease-related symptoms and impacts most important to patients with CAD, and to evaluate whether existing patient-reported outcome (PRO) measures are appropriate to assess relevant CAD concepts. Methods As part of a larger study, qualitative concept elicitation (CE) interviews were conducted to better understand the disease burden of CAD from the patient perspective. The results from the first set of interviews were reported by Su J et al. Blood 2020;136(1):29-30. Based on the identified symptoms and impacts, standard survey methodological principles were used to develop a draft item pool to address concepts of interest. Items were refined and evaluated during the second set of interviews, which included 3 rounds of 60-minute phone interviews with patients with CAD using a semi-structured interview guide that included a CE section and cognitive debriefing. Pooled results from both sets of interviews were used to develop a conceptual model of the symptoms and impacts of CAD. Physician advisors were also invited to review the concepts identified in the interviews and to select those that they believed were most relevant as part of an advisory board. A PubMed review of literature published between 2010-2020 was also conducted to identify existing PRO measures used in the assessment of symptoms, impacts, and/or quality of life and patient experiences in adults with CAD or similar disease areas. Identified PRO measures were assessed to determine the extent to which they captured CAD-specific concepts identified in the CE interviews. Results In total, 37 participants diagnosed with primary or secondary CAD took part in the interviews (Set 1, n=16; Set 2, n=21). Overall, the mean age of participants was 67.2 years (range: 35-87), and the majority were female (73%). The most frequently reported symptom of CAD was reactions to cold environments (n=36; 97%), e.g., cold or numb feet/hands, and skin discoloration. Other reported symptoms included fatigue (n=35; 95%), shortness of breath (n=28; 76%), and trouble with thinking/concentration (n=21; 57%). The most frequently reported unfavorable impact of CAD was on day-to-day activities (n=32; 87%). Other negative impacts included effects on enjoyable activities (n=29; 78%) e.g., gardening, physical health/activities (n=28; 76%), social/leisure life (n=26; 70%); and mood/emotions (n=24; 65%). Most participants (n=30; 81%) reported they had made lifestyle/behavioral changes to help limit their CAD symptoms, such as wearing extra clothing in places that were likely to be cold. A conceptual model of the symptoms and impacts of CAD was developed based on these data (Figure 1). Physician advisors (n=7) agreed that the patient-reported symptoms and impacts identified during the interviews were relevant concepts to CAD. Following a literature review, no existing PRO measure was found to adequately address concepts deemed critical to CAD from the patient perspective. Owing to the lack of an existing fit-for-purpose measure, 14 concepts were identified from the interviews to develop an initial draft item pool. During the cognitive debriefing in the second set of interviews, participants (n=21: Round 1 n=8; Round 2 n=7; Round 3 n=6) evaluated these concepts. After 3 rounds of interviews, the new item set yielded 11 items relating to: fatigue; cold sensitivity; dyspnea; wearing extra clothing; limited physical, social, and enjoyable activities; difficulty with usual activities; mood; frustration; and anxiety/stress. Participants reported these items were comprehensive of their experiences with CAD, easy to understand, and would be relevant to gaining a better understanding of individuals' experiences with CAD. Conclusion These results support the need for a novel PRO measure(s) that adequately addresses concepts critical to the measurement of CAD symptoms and impacts from the patient perspective. Figure 1 Figure 1. Disclosures Joly: Sanofi: Current Employment. Dasmahapatra: Sanofi: Current Employment, Current equity holder in publicly-traded company. Su: Sanofi: Current equity holder in publicly-traded company, Ended employment in the past 24 months; Astellas US LLC: Current Employment. DiBenedetti: RTI Health Solutions: Current Employment, Other: Employee of RTI Health Solutions, funded by Sanofi Genzyme to conduct the original work which this abstract is based on. Kosa: RTI Health Solutions: Current Employment. Hill: Novartis: Consultancy, Honoraria; Grifols: Consultancy, Honoraria; Sanofi: Consultancy; ReAlta: Consultancy; Alexion: Honoraria; Amgen: Honoraria; Argenx: Consultancy; Apellis: Consultancy, Honoraria.

The Burden of Cold Agglutinin Disease on Patients’ Daily Life: an Online Survey of 50 American Patients (Preprint)

BACKGROUND Cold agglutinin disease (CAD) is a rare and poorly understood disorder affecting 15% of patients with autoimmune hemolytic anemia. Few studies have assessed CAD symptoms and their impact on daily life, and these did not address the patients’ perspective. OBJECTIVE The aim of this research is to increase the knowledge on CAD through a patient-centric survey and to gain a better understanding of the burden of this disease. METHODS We conducted an internet-based survey in September 2020 among American patients registered on the CAD Unraveled website and members from the Cold Agglutinin Disease Foundation. RESULTS Fifty respondents were included in the study. Ninety percent of patients reported having experienced fatigue. Fatigue was mainly reported on a daily basis, and almost a third said it was constant through the day. It has also been shown that CAD had a great impact on physical well-being, emotional well-being, social life, and patients’ household finances. The disease varies over time, with or without symptoms. Eighty-eight percent of patients reported previous episodes of increased intensity/sensitivity of their CAD symptoms, with a mean number of episodes reported of 4.5 during the past year. More than half of the patients considered their disease as moderate or severe, and over 40% of the study group reported that their symptoms had worsened since the time of diagnosis. CONCLUSIONS Our study has raised new data on CAD symptoms, in particular on the importance and type of fatigue, and the fluctuation of CAD symptoms.

Diagnosis and management of cold agglutinin disease associated with low-grade B-cell lymphoma in a patient receiving pembrolizumab for lung cancer

A 65-year-old with non-small cell lung cancer developed autoimmune haemolytic anaemia while receiving pembrolizumab containing chemoimmunotherapy. Initially thought to be due to pembrolizumab induced haemolysis, he was treated with steroids, and pembrolizumab was held. Haemolysis was refractory to steroids and blood was observed to agglutinate in cold room temperatures. Cold agglutinins in high titre and monoclonal serum IgM kappa protein were detected. Bone marrow biopsy showed marginal zone lymphoma confirming low grade B-cell lymphoma causing cold agglutinin disease. B-cell depletion by rituximab stopped haemolysis, and pembrolizumab was safely continued for lung cancer.