Recurrent Vaso-occlusive Crises Research Articles

Casgevy (exagamglogene autotemcel) and Lyfgenia (lovotibeglogene autotemcel) for individuals 12 years and older with sickle cell disease (SCD) and recurrent vaso-occlusive crises (VOC): A therapeutics bulletin of the American College of Medical Genetics and Genomics (ACMG)

Casgevy (exagamglogene autotemcel) and Lyfgenia (lovotibeglogene autotemcel) for individuals 12 years and older with sickle cell disease (SCD) and recurrent vaso-occlusive crises (VOC): A therapeutics bulletin of the American College of Medical Genetics and Genomics (ACMG)

Exploring the role of viscosity-vaso-occlusion and haemolysis-endothelial dysfunction in pain sensitization among Jamaicans with sickle cell disease.

Viscosity-vaso-occlusion (VVO) and haemolysis-endothelial dysfunction (HED) are pathophysiological mechanisms and clinical subphenotypes of sickle cell disease (SCD). Recurrent vaso-occlusive crises (VOC) may lead to neuroplastic changes and pain sensitization. Among 257 SCD participants, we assessed the relationship of subphenotypes with pain sensitivity using quantitative sensory testing to identify heat pain thresholds (HPT) and pressure pain thresholds (PPT). VOC history and sleep, social and emotional functioning were assessed using the adult sickle cell quality of life measurement information system. The 'elbow method' determined the optimal number of clusters as three. Clustering was performed using K-prototypes. Among clusters 2 and 3, VOC frequency and severity were higher. Clusters 1 and 3 had lower haemoglobin, higher reticulocytes and lactate dehydrogenase and more leg ulcers. In multivariate regression, cluster 3 was associated with approximately 13.6% lower PPT compared to cluster 1, and female sex was associated with decreases in PPT and HPT at the hands and feet (p < 0.001). Hydroxyurea use and unit increases in sleep functioning and age were associated with approximately 20.1% higher foot-PPT, 6.8% higher hand-PPT and 2.5% higher hand-HPT and foot-HPT respectively. Findings suggest that a third subphenotype with mixed VVO and HED features and worse pain sensitization may exist.

Regulatory Assessment of Casgevy for the Treatment of Transfusion-Dependent β-Thalassemia and Sickle Cell Disease with Recurrent Vaso-Occlusive Crises.

Sickle cell disease (SCD) and transfusion-dependent β-thalassemia (TDT) are hereditary haemoglobinopathies characterized by a reduction in functional β-globin chains. Both conditions cause tiredness and increase susceptibility to infection, which can lead organ failure, significantly reducing life expectancy and typically requiring those affected to undergo regular erythrocyte transfusion. Recently, a novel therapeutic treatment for SCD and TDT was approved by the UK regulatory body (Medicines and Healthcare products Regulatory Agency; MHRA). Exagamglogene autotemcel (Casgevy) is the first licensed therapy globally to utilize CRIPSR/Cas9 technology and induces an increase in expression of γ-globin chains to compensate for the reduction in functional β-globin. Casgevy represents a first-in-class therapeutic, and numerous considerations were made by the MHRA throughout its assessment of the medicine. These include, but are not limited to, the risk of tumorigenicity and off-target editing, a limited cohort size, the validity of proposed dosing and the conduction of only single-arm studies. The MHRA's analyses of the data to support the proposed indications are presented and discussed throughout this manuscript. Overall, the sponsors claims were considered well supported by their data, and Casgevy was licensed for the treatment of TDT or SCD in patients 12 years of age and older for whom hematopoietic stem cell (HSC) transplantation is appropriate, but a human leukocyte antigen-matched related HSC donor is not available.

EE369 Healthcare Resource Utilization Among Patients With Sickle Cell Disease With Recurrent Vaso-Occlusive Crises in Canada

EE369 Healthcare Resource Utilization Among Patients With Sickle Cell Disease With Recurrent Vaso-Occlusive Crises in Canada

EE132 Economic Outcomes and Real-World Adherence of Patients With Sickle Cell Disease With Recurrent Vaso-Occlusive Crises Treated With L-Glutamine, Voxelotor, and Crizanlizumab in the United States

EE132 Economic Outcomes and Real-World Adherence of Patients With Sickle Cell Disease With Recurrent Vaso-Occlusive Crises Treated With L-Glutamine, Voxelotor, and Crizanlizumab in the United States

Characterizing the Immature Immunophenotype of Sickle Cell Disease Monocytes.

Sickle cell disease (SCD) is marked by episodic vaso-occlusive crisis (VOC). Recurrent VOC creates a pro-inflammatory state that induces phenotypic alterations in innate immune cells. Monocytes are of particular interest to VOC pathophysiology because they are especially malleable to inflammatory signaling. Indeed, inflammatory disease states such as chronic obstructive pulmonary disease (COPD), obesity and atherosclerosis are known to influence monocyte development and alter monocyte subpopulations. In this study, we describe SCD monocyte subsets by performing immunophenotypic flow cytometric, enzymatic, and morphologic analysis on peripheral blood. Herein, we add to the growing body of evidence suggesting aberrant monocyte populations underpin VOC pathophysiology. We found that SCD monocytes possess an immature phenotype as demonstrated by 1) decreased CD4 positivity (p < .01), 2) low α-naphthyl butyrate esterase(ANBE) expression, and 3) naïve morphologic features. We additionally found an increase in CD14+CD16-CD4- monocytes (p < .01), a subset associated with the impaired immune response of post-trauma patients. Interestingly, we also found a large proportion of CD14+CD4-HLA-DR- monocytes which, under normal circumstances, are exclusively found in neonates (p < .01). Finally, we report an increase in nonclassical monocytes (CD14dimCD16+), a subset recently shown to have a critical role in prevention and recovery from VOC.

Assessment of hypoxemia among young adults with sickle cell anaemia in steady state in southwestern Nigeria: a crosssectional study.

Hypoxia is a known feature of sickle cell anaemia (SCA) which results from chronic anaemia and recurrent vaso-occlusive crisis (VOC) which can cause tissue ischaemia that leads to an end organ damage. The hallmark of SCA is chronic anaemia and recurrent vaso-occlusive crisis. The aim of this study is to compare the oxygen saturation of sickle cell anaemic individuals with the normal haemoglobin type (Hb AA) control and also to determine the prevalence of hypoxemia among SCA. Two-hundred and twenty-two (136 Hb SS and 86 Hb AA) participated in the study. The mean ± SD of age (years), oxygen saturation (%) and pulse rate (bpm) of participants with sickle cell anaemia and Hb AA control were 21.85 ± 3.04 and 22.14 ± 3.18 (t = 0.701, p = 0.436), 95.21 ± 3.02 and 98.07 ± 0.81 (t=-8.598, p < 0.0001) and 77.10 ± 9.28 and 73.16 ± 8.52 (t = 3.173, p = 0.002) respectively. The prevalence of hypoxemia among SCA participants was 47.1%. Prevalence of hypoxemia in males with SCA was 60.9% while 39.1% of the females had hypoxemia.

Casgevy and Lyfgenia: Two gene therapies for sickle cell disease.

Two cell-based gene therapies – exagamglogene autotemcel (Casgevy – Vertex) and lovotibeglogene autotemcel (Lyfgenia – Bluebird Bio) – have been approved by the FDA for treatment of sickle cell disease in patients ≥12 years old with recurrent vaso-occlusive crises. They are the first gene therapies to be approved in the US for use in sickle cell disease; Casgevy is the first treatment to be approved in the US that uses CRISPR/Cas9 gene-editing technology.

Exagamglogene Autotemcel: First Approval.

Exagamglogene autotemcel (Casgevy™) is a genetically modified autologous CD34+ cell enriched population. It contains human haematopoietic stem and progenitor cells edited ex vivo by CRISPR/Cas9 (a DNA double strand break-inducing nuclease system) to differentiate into erythroid cells that produce high levels of foetal hemoglobin. Developed by Vertex Pharmaceuticals and CRISPR Therapeutics, exagamglogene autotemcel received its first approval on 16 November 2023 in the UK for the treatment of transfusion-dependent β-thalassemia (TDT) in patients aged ≥ 12years for whom haematopoietic stem cell (HSC) transplantation is appropriate and a human leukocyte antigen matched related HSC donor is not available. On the same day, it was also approved in the UK for the treatment of sickle cell disease (SCD) in patients aged ≥ 12years with recurrent vasoocclusive crises (VOCs) who have the βS/βS, βS/β+ or βS/β0 genotype for whom HSC transplantation is appropriate and a human leukocyte antigen matched related HSC donor is not available. Subsequently, exagamglogene autotemcel was approved in the USA on 8 December 2023 for the treatment of SCD in patients aged ≥ 12years with recurrent VOCs and received a positive opinion in the EU on 14 December 2023 for the treatment of TDT and SCD. A regulatory assessment of exagamglogene autotemcel is currently underway for the treatment of TDT in the USA. This article summarizes the milestones in the development of exagamglogene autotemcel leading to these first approvals.

EE278 Model-Projected Long-Term Clinical Outcomes of Exagamglogene Autotemcel (exa-cel) Gene-Edited Therapy in Patients with Sickle Cell Disease with Recurrent Vaso-Occlusive Crises in the United Kingdom

EE278 Model-Projected Long-Term Clinical Outcomes of Exagamglogene Autotemcel (exa-cel) Gene-Edited Therapy in Patients with Sickle Cell Disease with Recurrent Vaso-Occlusive Crises in the United Kingdom

Improving the Outpatient Pain Management Plan for Patients with Sickle Cell Disease with Electronic Medical Record-Based Pain Action Plans

Background: Patients with sickle cell disease (SCD) experience recurrent vaso-occlusive crises (VOC) as a primary manifestation of their illness. The American Society of Hematology (ASH) best practice guidelines recommend that individuals with SCD have individualized care plans to effectively begin pain management at home prior to presenting to the emergency room. A needs assessment of the comprehensive sickle cell program at Rady Children's Hospital San Diego (RCHSD) identified the need for a standardized approach for the provision of Pain Action Plans (PAP). In 2022, an outpatient PAP Quality Improvement (QI) project was initiated at RCHSD with the global aim to improve outpatient pain management and quality of life for patients with SCD. SMART Aim: Within 6 months (January-June 2023), to increase the proportion of patients with SCD receiving a PAP during a comprehensive clinic visit from 0 to 50%. Methods: The QI project was conducted by an interprofessional team with clinical, QI, and information technology expertise. An initial approach utilizing the Med Action Plan function in EPIC had technical challenges and was not implemented. We identified an existing Epic Asthma Action Plan which could be adapted to a SCD PAP. Meetings with clinical informaticists, pulmonology (consultants), and hematology teams informed the QI tools (process mapping, key driver and Ishikawa diagrams) that we used to design our PDSA cycles. The PAPs were modeled after the existing Asthma Action Plan, with green, yellow, and red zones to indicate different levels of pain management. Patients were given laminated Youth Acute Pain Functional Ability Questionnaire (YAPFAQ) and a comfort measures sheet to complete prior to their visit with the provider to inform the PAP which included pain medication details and supportive care measures for each zone. PAPs were created within the clinic note at comprehensive clinic visits and then provided to the family as a printed letter in person and via MyChart (if activated). Our outcome measure was the percentage of patients who were provided a PAP at their SCD comprehensive clinic visit. Process measures included the percentage of patients who had documentation in the PAP of the YAPFAQ and comfort measures, percentage of patients who had a PAP routed to patient via MyChart, percentage of patients who confirmed receipt of their PAP, percentage of patients who had used their PAP by parental report after one week, and percentage of patients who had used their PAP after 3 months per Epic documentation. Balancing measures were the perceived burden of patient care/documentation for the PAP to be evaluated with pre and post surveys among providers. Results: Interventions were evaluated using PDSA cycles. PDSA Cycle 1 (January-March 2023) included development of the SCD PAP by adapting the existing Asthma Action Plan to a SCD PAP. This included the creation of medication templates, integrating comfort measures and pain triggers, creating EPIC smart phrases to document the YAPFAQ. We educated providers on the SCD PAP and documentation process and worked with the interdisciplinary team including case managers, nurses, child life specialists, and psychologist to incorporate YAPFAQ and comfort measures into the comprehensive clinic visit. PDSA Cycle 2 (April-June 2023) included additional education, training, and targeted e-mail reminders to hematology attendings. From May 2023 to July 2023, 94% percent (13/14) of patients seen at a comprehensive clinic visit received a PAP. One patient had the PAP created but did not receive the printed letter due to time constraints for family. Feedback from families indicated that they felt the PAP was a valuable tool to have at home during VOC, however none had yet utilized it in the week since they were seen in clinic. Early provider feedback has indicated that this functionality is easy to use and efficient during the comprehensive clinic visit. Conclusion: The adaptation of the Asthma Action Plan to the SCD PAP allowed for successful implementation of PAPs for our patients with SCD. Subsequent PDSA cycles will focus on optimizing implementation in the clinic and utilization for pain events. We will evaluate the clinical impact of the PAPs on pain management outcomes.

1307. Vaso-occlusive Crisis is Associated with Subsequent Osteomyelitis in Pediatric Sickle Cell Disease

Abstract Background Children with sickle cell disease (SCD) commonly develop microvascular infarcts of bone known as vaso-occlusive crisis (VOC) and are also at high risk of osteomyelitis (OM). VOC and OM can be challenging to distinguish due to overlapping clinical features. VOC might predispose to OM, or an initial misdiagnosis of OM as VOC might lead to delayed diagnosis of OM. This study aimed to test whether VOC was associated with subsequent development of OM in children with SCD. Methods A retrospective Pediatric Health Information System (PHIS) database study (2010-2021) was performed. ICD-code data related to common diagnoses in pediatric patients with SCD were extracted. The rate of VOC within 30 and 180 days preceding episodes of OM was compared to the rate preceding acute chest syndrome (ACS), another common diagnosis in children with SCD but unlikely to be anatomically related to OM. Odds ratios (OR) were used to evaluate the association between these diagnoses. Results Of 22,818 PHIS participants with SCD, 13,699; 450; and 7,327 had ≥ 1 episode of VOC, OM and ACS, respectively. The distribution of OM diagnoses was similar across pre-specified age groups (0-4, 5-12, and 13-18 years). The odds ratio of VOC preceding a diagnosis of OM vs. ACS was 2.15 within 30 days (95% CI: 1.82-2.54; p= 3.68 x 10-18), and within 180 days was 1.39 (95% CI: 1.20-1.62; p=2.04 x 10-5). VOC Preceding Osteomyelitis vs. Acute Chest Syndrome Conclusion VOC was significantly more common in the days preceding a diagnosis of OM than of ACS. The strength of association was stronger within 30 days prior to OM than 180 days. These results suggest possible misdiagnosis of OM since VOC might delay OM diagnosis in some cases, that recurrent VOC might be misdiagnosed as OM, or that VOC can directly contribute to risk of OM in some cases. Limitations of this study include possible incomplete adjustment for unmeasured variables which could confound the analysis. More research is needed to confirm and evaluate the mechanism behind this association. Understanding the relationship could lead to improved screening and treatment of both VOC and OM. Disclosures Joshua Wolf, MBBS, PhD, Karius Inc.: Grant/Research Support|Merck Inc.: Participation in industry-sponsored research Sandra Arnold, MD, Contrafect: Grant/Research Support|Enanta: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support

Title: The Impact of Recent Vaso-Occlusive Crisis on Health-Related Quality of Life in Adults with Sickle Cell Disease

Introduction: Sickle cell disease (SCD) is characterized by vaso-occlusive crises (VOCs) and a progressive clinical course, often leading to end organ damage and mortality. Individuals living with SCD with recurrent VOCs experience daily life disruptions due to recurrent pain crises, debilitating chronic pain and fatigue, which substantially impair health-related quality of life (HRQoL). The impact of a recent VOC on HRQoL has not been quantified. We investigated HRQoL impacts in adults with SCD who experienced a recent VOC (&amp;lt; 1 week) in comparison to overall adults with SCD with recurrent VOCs. Methods: A mixed-methods study was conducted to quantify the HRQoL, work impacts, and perceived health inequalities of individuals with SCD with recurrent VOCs. The study consisted of qualitative interviews and an online longitudinal survey administered at 3 timepoints (month 0, 3, and 6) in the US, UK, France, Germany, and Italy. Patient advocacy groups used multi-channel outreach to invite participants, who were required to meet the eligibility criteria and provide consent. Key eligibility criteria included recurrent VOCs defined as ≥ 2 VOCs/year in each of the 2 years prior to enrollment requiring a medical facility interaction and administration of pain medication or red blood cell transfusion. The survey included multiple patient-reported outcome (PROs) measures: the Functional Assessment of Cancer Therapy - Bone Marrow Transplant (FACT-BMT) inclusive of the FACT-General (FACT-G), EuroQol- 5 Dimension 5-Level (EQ-5D-5L), 11-point pain numerical rating scale (NRS), Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me), and the Work Productivity and Activity Impairment (WPAI) questionnaire. In this post-hoc analysis study participants with a current or recent VOC (&amp;lt; 1 week ago) were identified based on ASCQ-Me responses (herein referred to as recent VOC). The HRQoL impact of a recent VOC was assessed by descriptively comparing PRO scores between those with a recent VOC and the overall population of adults with SCD with recurrent VOCs (herein referred to as overall population). Results: The survey was completed by 142 participants with SCD (≥ 18 years) with 139 providing time since last VOC living in the US (n=82) and UK, Germany, France, and Italy (n=57). Fifty-six (40.3%) reported a recent VOC and had a similar mean age (35.7 vs. 35.3 years) and hydroxyurea use in the past month (58.9% vs. 61.9%) compared with the overall population. A higher proportion of those with a recent VOC were unemployed or unable to work due to SCD (76.8% vs. 64.7%). The mean EQ-5D VAS (0-100 scale, 100=best health) among those with a recent VOC was 49.2 (SD: 14.2), which was 16.2% and 38.8% lower relative to the overall study population (58.7 [SD: 19.4]) and the US general population (80.4 [SD: 15.6]), respectively. The overall mean EQ-5D health utility US index score (0.59 [SD: 0.27]) was much lower than the US general population (0.85 [SD: 0.21]) and further reduced among those with a recent VOC by 0.11 (0.48 [SD: 0.25]). The FACT-G total mean score was 53.6 (SD: 14.3) (0-108 scale, 108=best HRQoL) among those with a recent VOC representing a clinically meaningful reduction compared with the overall population (62.5 [SD:18.1]); with all FACT-G domain scores negatively impacted by a recent VOC. Based on the WPAI, those employed with a recent VOC (n=15) reported a mean of 35.4% (SD: 35.8%) absenteeism and 62.5% (SD: 21.8%) presenteeism, which were higher than the overall study population (24.7% [SD: 27.1%] and 42.0% [SD: 27.8%)], respectively). In the past 12 months, those with a recent VOC had a greater mean number of emergency room visits (9.6 [SD: 12.6] vs 6.2 [SD: 8.8]), hospitalizations with overnight stays (6.0 [SD: 5.7] vs. 4.0 [SD: 4.5]), and days overnight in the hospital (21.8 days [SD: 32.9] vs. 14.7 [SD: 24.7]) compared to the overall population. Conclusions: Despite current treatments, nearly 40% of adults with SCD in the surveyed population experienced a recent VOC (&amp;lt; 1 week), which has significant negative impacts on HRQoL and functional status, including the ability to work. These results demonstrate the substantial humanistic burden of those living with SCD with recurrent VOCs and the additional impairment of a recent VOC. Novel treatments that reduce or eliminate VOCs may provide an opportunity to improve health inequalities, HRQoL, and address unmet needs in this patient population.

Real-World Experience of Individuals with Sickle Cell Disease Treated with Voxelotor: Initial Report from the Multicenter, Prospective Prospect Study

Introduction: Sickle cell disease (SCD) is an inherited blood disorder in which sickle hemoglobin (HbS) polymerization results in red blood cell sickling, which in turn leads to chronic hemolytic anemia, unpredictable pain episodes, and recurrent vaso-occlusive crises (VOCs). Hemolysis and low hemoglobin (Hb) are associated with organ damage, increased morbidity, and early mortality. Voxelotor, a first-in-class HbS polymerization inhibitor, is approved in the US for the treatment of patients with SCD aged ≥4 years and in Europe for the treatment of hemolytic anemia due to SCD in patients aged ≥12 years. In the phase 3, randomized, controlled HOPE (NCT03036813) and the phase 2, open-label HOPE-KIDS 1 (NCT02850406) trials, patients treated with once daily oral voxelotor experienced increased Hb levels and reductions in markers of hemolysis at Week 24 compared with baseline. Here we report the first efficacy and safety data from patients with SCD enrolled in the prospective PROSPECT registry who received voxelotor in a real-world setting. Methods: PROSPECT (NCT04930445) is a post-marketing, open-label, observational, prospective patient registry of patients with SCD (aged ≥4 years) in the US. Eligible participants are being treated with voxelotor as prescribed by their physician as part of their usual care. Participants are treated and evaluated per standard of care and at the physician's discretion. Treatment, including interruptions and restarting treatment, continue at the discretion of the treating physician. Patients receive any additional medications or transfusions as determined and prescribed by their physician. Follow-up duration is 5 years after the first dose of voxelotor therapy. Study data are collected from patient medical records and secondary data sources and entered in case report forms via an electronic data capture system. Results: At data cutoff (May 30, 2023), 85 patients were enrolled at 5 sites. The mean (SD) age was 33.2 (15.3) years, 51.8% of patients were female, and most (92.9%) were Black or African American. Overall, 72.9% of patients were genotype HbSS, 62.4% were taking concurrent hydroxyurea, and mean (SD) Hb at baseline was 7.7 (1.53) g/dL. The mean (SD) duration of treatment, excluding gaps, was 47.0 (12.35) weeks. At the data cutoff, 76 patients (89.4%) continued voxelotor treatment; 7 patients (8.2%) never started voxelotor, and 2 patients (2.4%) discontinued treatment because of adverse events (AEs).The initial prescribed daily doses of voxelotor were 1500 mg (84.7%), 1000 mg (8.2%), 900 mg (4.7%), or 500 mg (2.4%). The most common reasons for prescribing voxelotor were to reduce either anemia (74.1%), frequency of VOCs (15.3%), pain (14.1%), or the frequency of blood transfusion (9.4%); multiple reasons could be selected. In 66 patients with recorded baseline and posttreatment Hb values, the observed mean (SD) peak posttreatment Hb value was 9.0 (1.75) g/dL, representing a mean (SD) increase from baseline of 1.3 (1.25) g/dL. The range of peak Hb change from baseline was −1.4 to 4.6 g/dL and 52/66 patients (78.8%) had a positive Hb response (Figure). Reductions in markers of hemolysis were also observed following voxelotor treatment, with nadir mean (SD) decreases from baseline of −23.9% (55.92%) in reticulocyte percentage (n=54), −1.8 (2.36) mg/dL in total bilirubin (n=61), and −1.6 (1.95) mg/dL in indirect bilirubin (n=38). AEs of special interest reported in &amp;gt;3% of patients included diarrhea, headache, nausea, abdominal pain, and rash (Table); most of these AEs were mild or moderate in severity. Conclusions: PROSPECT is the first prospective patient registry of voxelotor, with the potential to follow up to 1000 participants for up to 5 years and enable long-term, robust data collection of real-world care patterns that could inform how best to incorporate voxelotor into the treatment paradigm of patients with SCD. In this initial cohort of participants enrolled to date, following voxelotor treatment for a mean duration of 47.0 weeks, the mean peak increase from baseline in Hb was 1.3 g/dL, and associated reductions in markers of hemolysis were observed. Safety data were consistent with the phase 3 HOPE and HOPE-KIDS 1 trials. Overall, these initial findings provide support for the real-world safety, tolerability, and effectiveness of voxelotor treatment in individuals with SCD. While enrollment is ongoing, updated data will be regularly reported.

Improvements in Health-Related Quality of Life after Exagamglogene Autotemcel in Patients with Severe Sickle Cell Disease

Background: Severe sickle cell disease (SCD), which is characterized by recurrent vaso-occlusive crises (VOCs), has a substantial negative impact on health-related quality of life (HRQoL). Exagamglogene autotemcel (exa-cel) is a one-time, non-viral, ex vivo CRISPR/Cas9 gene-edited autologous cell therapy in phase 3 clinical trials that has been shown to eliminate VOCs. Here, we report HRQoL data from a pre-specified interim analysis of the exa-cel CLIMB SCD-121 study. Methods: CLIMB SCD-121 is an ongoing phase 3 trial of a single dose of exa-cel in patients ages 12-35 years with SCD and a history of ≥2 VOCs/year in each of the 2 years prior to screening. Changes in patient reported outcomes measures EuroQol Quality of Life Scale 5 dimensions 5 levels of severity (EQ-5D-5L, including descriptive system and visual analog scale [VAS]), Functional Assessment of Cancer Therapy Bone Marrow Transplant (FACT-BMT, including FACT-General [FACT-G] and bone marrow transplant subscale [BMTS]), Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me), and the 11-point pain Numerical Rating Scale (NRS ) were assessed from baseline through month 24 as a secondary endpoint in the trial. Data is presented as of 10 Feb 2023 for the 17 adult patients (aged ≥18-35 years) who had been followed for ≥16 months after exa-cel infusion. Results: Substantial and clinically meaningful improvements exceeding minimal clinically important difference (MCID) thresholds were observed in all assessed patient reported outcomes measures. At baseline, the EQ-5D-5L health utility US index (n=17; mean [SD]: 0.71 [0.23]) and EQ VAS (63.5 [22.5]) scores were lower than the US general population norm and similar to baseline scores reported for adult SCD patients with recurrent VOCs. By month 6, both EQ-5D-5L health utility US index score and EQ VAS score showed substantial improvements, which were maintained through month 24 (mean changes [SD] at month 24 [n=8]: 0.23 [0.20]; MCID 0.078 and 28.3 [16.2]; MCID 7 to 10, respectively). FACT-G Total Score improved from baseline at month 24 (mean [SD] change at month 24 [n=8]: 29.8 [17.2]; MCID 3 to 7), with improvements observed in all 4 subscales (physical, social/family, emotional, and functional well-being). BMTS score improved by month 6 and was sustained through month 24 (mean [SD] change at month 24 [n=8]: 3.9 [5.7]; MCID 2 to 3). All subscales of the ASCQ-Me, including emotional (mean [SD] change [n=7] 17.7 [9.8]), social (23.8 [6.7]), stiffness (7.9 [12.9]), and sleep impact (8.4 [8.3]), demonstrated clinically meaningful improvements from baseline through month 24. For the ASCQ-Me pain-related subscales evaluating pain impact, pain episode frequency and pain severity, the largest numerical improvement was observed in pain episode frequency (mean [SD] change at month 24 [n=8]: -22.8 [8.2]; MCID -5). Improvements in the pain NRS were observed by month 12 and sustained through Month 24 (mean [SD] change at month 24 [n=8]: -1.8 [3.1]; MCID -1). Conclusion: Adults infused with exa-cel reported sustained and clinically meaningful improvements in their HRQoL, with improvements observed across different instruments and domains, including physical, emotional, social/family, and functional well-being, pain experience, and overall health status. These results demonstrate the broad clinical benefits of exa-cel in patients with SCD.

Donor Hemoglobin Genotype Does Not Impact Outcomes Following Matched Related Donor Hematopoietic Cell Transplantation for Sickle Cell Disease: A STAR Study

Sickle cell disease (SCD) is an inherited hemoglobin (Hb) disorder which leads to significant morbidity and early mortality. Hematopoietic cell transplantation (HCT) is the only curative treatment with long-term outcome data, demonstrating excellent symptom-free survival particularly when a matched related donor (MRD) is available. Most MRD have sickle cell trait (Hb AS), but trait donor HCT is considered acceptable by the FDA and without negative impact. Further, initial gene addition and editing approaches for SCD have resulted in a trait-like status with benefit. Sickle trait, however, is associated with complications such as papillary necrosis, bacteriuria, splenic infarction, and exercise-induced death. The primary aim of this study was to compare long-term outcomes following MRD HCT for SCD based on donor Hb genotype, to objectively describe any impact on outcomes. Retrospective data was available for this analysis on 182 SCD patients ≥1 year post MRD HCT at 10 participating Sickle Transplant Advocacy and Research (STAR) Alliance centers. Summary statistics were presented as mean (standard deviation) for continuous variables and count (%) for categorical variables. Comparisons were made between Hb AA and Hb AS donor groups using both parametric and non-parametric tests for continuous variables and Chi-square test/exact test for categorical variables, with p-value &amp;lt;0.05 set as significant. Amongst 182 patients undergoing MRD HCT, 67% (n=122) had a Hb AS donor ( Table). In the overall cohort, median age at HCT was 8.7 (4.8) years and most patients had HbSS (n=174; 96%) with a severe clinical phenotype (n=97; 54%). HCT was performed using bone marrow (n=166; 92%) with myeloablative conditioning (n=156; 86%) in the majority. Patients with a severe disease phenotype and Hb AS donor were significantly more likely to have recurrent vaso-occlusive pain crises as an indication for HCT (p=0.033), otherwise there were no differences in baseline patient or HCT characteristics between cohorts. With mean post-HCT follow up of 4.5 (3.9) and 5.1 (4.1) years in Hb AA and Hb AS donor cohorts (p=0.145), no significant differences were seen in recipient outcomes including time to neutrophil and platelet engraftment, number of or time to last platelet transfusion, myeloid or unsorted % donor chimerism, number with acute (day 100) or chronic GVHD (1 year), or time to discontinue immunosuppression (data not shown). Disease recurrence and need for 2 nd HCT were rare in both cohorts (AA: 2 [3%] and 2 [3%]; AS: 3 [3%] and 4 [3%]; p=0.665 and 1.0, respectively). Two (3%) and 5 (4%) patients died in the AA and AS cohorts, respectively (p=1.0). Aside from a statistically (but not clinically) significant difference in Hb at day 30 (p=0.044), no difference was seen in longitudinal Hb or markers of hemolysis (LDH and ARC; Figure). No significant difference was seen in median number of RBC units transfused (AA: 4.0 [2.0-6.0]; AS: 3.0 [2.0-6.0]; p=0.454) or days to last transfusion (AA: 23.0 [14.0-77.0]; AS: 22.0 [13.0-75.0]; p=0.86). SCD complications were rare post-HCT, with no difference seen between cohorts in number (%) with VOC (AA: 1 [2%; had 2 separate VOC events]; AS: 3 [3%]; p=1.0), ACS (none reported), chronic pain (AA: 0 [0%]; AS: 1 [&amp;lt;1%]; p=1.0), or other SCD-related complications (AA: 2 [3%]; AS: 9 [7%; had 11 separate other events]; p=0.456). Stroke occurred in a significantly higher proportion with an AA versus AS donor (5 [8%] and 2 [2%], respectively; p=0.04). No significant differences were seen in longitudinal (1 and 2 years and at last follow up) post-HCT cardiac (EF, SF, TRJ velocity), pulmonary (FEV1, FVC, DLCO), or renal (GFR) function between cohorts (data not shown). Our results indicate that in MRD HCT for SCD, AS and AA donors yield comparable long-term outcomes. In this retrospective and registry-based study design, detailed analyses did not show differences between the two cohorts at baseline or at any timepoint post-HCT. While there were some outcome differences between the cohorts, they were either not clinically significant or did not have a scientific rationale, and thus were likely due to chance alone (denoted by bolding in Table). Given the young age of our cohort at HCT and thus a smaller proportion with SCD-related organ dysfunction, our results may not be applicable to an older cohort with significant organ dysfunction which will require a separate analysis.

Erythrophagocytosis Mediated By Circulating Monocytes Is Induced By Distinct Mechanisms Depending on the Disease

Stress erythropoiesis (SE) occurs when the steady state erythropoiesis is no longer sufficient to sustain the number of healthy red blood cells (RBC) needed in the circulation. There is an extension of this activity to extramedullary sites, contributing to the increase in cell production in the erythroblastic island (EBI) niche, and altered or damaged RBCs are then cleared by macrophages. Some diseases have a state of chronic SE. Sickle cell anemia (SCA) affects multiple aspects of RBCs, leading to recurrent vaso-occlusive crisis, hemolytic anemia, and inflammation. Polycythemia Vera (PV), an acquired neoplastic disease with mutations in JAK2 kinase, is characterized by the overproduction of RBCs, increasing blood viscosity, and resulting in a higher risk of thrombotic events. We previously showed that circulating monocytes (MC) of both diseases have a phenotype similar to the EBIs macrophages, with higher expression of CD169, CD163, CD206 and VCAM-1, and also participate in the phagocytosis of RBCs, function typically carried out by macrophages. Therefore, the aim of this study was to determine whether the increased phagocytic activity found in these patients was due to the alterations on the MCs phenotype or if it was an influence of the RBCs, as well as investigate the consequences to the iron metabolism after phagocytosis. MCs from peripheral blood were isolated and incubated for 2 hours with previously stained RBCs, to allow the phagocytosis to happen. After this period, the remaining RBC were lysed and the antibodies anti-intracellular heme-oxigenase-1 (HO-1) and anti-membrane ferroportin (FPN) were used for flow cytometry analysis. The statistical analysis was done by paired t-student test (P&amp;lt;0.05). When exposed to SCA RBCs, MCs from SCA patients and healthy controls (HC) show higher phagocytic capability, than when exposed to HC RBCs (MC HC 22.9±8 vs 9.4±1.1, **P=0,0099; MC SCA 33.6±11.4 vs 16.4±11, **P=0,0054; respectively). The same happens to PV and HC MCs: when exposed to PV RBCs: they show higher phagocytosis compared to the presence of HC RBCs (MC HC 9.3±4.4 vs 2.8±4.7, **P=0.0065; MC PV 21.3±6.1 vs 11±6.8, *P=0.0146; respectively). Investigating the role of MCs in this activity, we compared SCA, PV and HC MCs in the presence of patients RBCs. SCA MCs internalized RBCs similarly to HC MCs (P=0.0699); on the other hand, PV MCs presented higher phagocytic capability when compared to HC MCs (**P=0.0022). In all groups, the expressions of both HO-1 and FPN were higher in those MCs that participated in the phagocytosis than in those that didn't contribute to this function (HO-1: MC SCA 91.9±4 vs 65.9±16.8, **P=0.0098, MC PV 92.1±5.5 vs 61.7±15.5, ***P=0.0007; FPN: MC SCA 81.8±13.8 vs 66.5±15.7, ***P=0.0003, MC PV 70.9±17 vs 53.2±16.5, **P=0.0013 respectively). This indicates an increase in the ability to degrade heme and export iron post-phagocytosis. The results suggest that RBCs from patients with SCA are the ones responsible for the increase in the phagocytic activity by MCs, indicating that RBCs clearance is not an innate function of SCA MCs, even though they are active participants in the circulation. For PV, both RBCs and MCs seem to contribute to the increase of this process in the circulation of patients. The higher expression of molecules related to the iron metabolism suggests a participation of circulating MCs to the iron disponibility, helping with the maintenance of stock for the erythrocytic production. Even though SCA and PV have different pathophysiology, they both present SE and the circulating MCs from both groups show an important participation in the clearance of RBCs, either by an intrinsic function of MCs or a direct influence of changes in the RBCs, suggesting the important contribution of MCs to avoid oxidative stress and help with iron disponibility for erythropoiesis during the course of SE.

Safety Profile of Crizanlizumab 5.0 Mg/Kg in Sickle Cell Disease: Pooled Data from Clinical Trials

Introduction: Crizanlizumab is a humanized monoclonal antibody that binds to P-selectin and blocks its interaction with its ligands, including P-selectin glycoprotein ligand 1. It is approved to reduce the frequency of or prevent recurrent vaso-occlusive crises (VOCs) in patients aged ≥16 years with sickle cell disease (SCD). This pooled analysis assesses the safety of the recommended dosage of crizanlizumab (5.0 mg/kg monthly) in treated patients. Methods: Safety was assessed based on two clinical program data pools. Pool 1 comprised data from the crizanlizumab-treated groups from 3 Phase 2 studies (SUSTAIN [NCT01895361], SOLACE-adults [NCT03264989], and the pediatric SOLACE-Kids [NCT03474965]) and 1 Phase 3 study (STAND [NCT03814746]) in patients with SCD, with a history of VOCs leading to a healthcare visit. Pool 2 included data from the SUSTAIN and STAND treatment groups and the corresponding placebo group. Adverse events (AEs) were summarized by preferred term /system organ class and seriousness/severity per MedDRA version 23.1, with severity assessed based on CTCAE v5. Based on both its mechanism of action and the fact that crizanlizumab is a mAb, AEs of special interest (AESIs) included infections, infusion-related reactions (IRRs, events typically occurring within 24 hours of the recent crizanlizumab infusion), effects on hemostasis, and immunogenicity (antidrug antibodies [ADAs]). Pooled incidences of treatment-related AEs (TRAEs), suspected to be related to study treatment, were also evaluated. Results: In Pool 1, 245 patients received crizanlizumab 5.0 mg/kg (median age: 24 years [range,12-65]; 54.3% female), with 66.1% having 1 to 4 VOCs and 33.1% having ≥5 VOCs (VOC data were missing for 0.8% patients) at baseline. Pool 2 had 150 patients in the 5.0 mg/kg treatment group (median age: 27 years [range, 12-64]) and 147 patients in the placebo group (median age: 26 years [range, 12-68]). Median crizanlizumab exposure was 87.4 weeks (range, 2-228) in Pool 1, 54.1 weeks (range, 51.9-93.9) in Pool 2 treatment group and 53.3 weeks (range: 50.3-86.0) in the Pool 2 placebo group. The use of crizanlizumab in combination with hydroxyurea/hydroxycarbamide did not result in meaningful differences in safety profile. Most frequently reported AE in Pool 1 were headache (25.7%), pyrexia (22.9%), arthralgia (18.4%), nausea (16.7%), and COVID-19 (15.9%). In Pool 2 (treatment group vs. placebo), the most common AEs were headache (21.3% vs. 17.7%), pyrexia (19.3% vs. 17.7%), and nausea (17.3% vs. 10.2%). Infection events were observed in 62.4% and 56.7% of patients in the Pool 1 and 2 treatment groups, respectively, and in 55.1% in the placebo group (Table 1). The most common infections in Pool 1 were COVID-19 (15.9%), upper respiratory tract infections (12.7%), and urinary tract infections (11.8%). No increased risk or severity of infection was found in patients treated with crizanlizumab. IRRs occurred in 38.8% of Pool 1, 36.7% of the Pool 2 treatment group, and 27.9% of the placebo group. Most common IRRs were headache and nausea (Table 1). IRRs with grade ≥3 occurred in 3.3% of patients in Pool 1, with no grade 4 or 5 events. Bleeding-related events were observed in 16.7% of Pool 1 patients; epistaxis (3.7%) was the most reported. Treatment-induced ADA were reported in 0.8% (n=2) of patients in Pool 1, confirming the low immunogenic potential of crizanlizumab. TRAEs were observed in 31.8% patients in Pool 1, 34.7% in the Pool 2 treatment group, and 24.5% in the placebo group. Among the patients in Pool 1, 10 (4.1%) experienced grade 3 or higher TRAEs. The most reported TRAEs are listed in Table 1. Treatment-related serious AEs occurred in 10 patients (4.1%), with 7 (2.9%) experiencing ≥ grade 3 AEs in Pool 1. Treatment discontinuation due to AEs occurred in 3.3% of patients in Pool 1, 2.7% in the Pool 2 treatment group, and 3.4% in the placebo group. Five on-treatment deaths were reported across the four studies and were considered not related to crizanlizumab by the investigator (myocardial infarction, multiple organ dysfunction, endocarditis, meningitis bacterial, and sepsis [1 patient each]). Conclusion: This pooled analysis of crizanlizumab 5.0 mg/kg in patients with SCD and a history of VOCs showed that crizanlizumab was well tolerated, with a favorable safety profile. Most AEs were mild to moderate, and the discontinuations due to AEs were infrequent. No new safety concerns were identified.

Characterizing the Immature Immunophenotype of Sickle Cell Disease Monocytes during Vaso-Occlusive Crisis

Sickle cell disease (SCD) is marked by episodic vaso-occlusive crisis (VOC). Painful VOC is the leading cause of emergency room visits and hospitalization in SCD, contributing heavily to the morbidity and mortality of this disease. Recurrent VOC creates a pro-inflammatory state that induces phenotypic alterations in the innate immune system. This inflammation-induced immune profile remodeling results in chronically active monocytes and neutrophils that antagonizethe vascular endothelium and further predispose SCD patients to VOC. While the mechanism of neutrophil involvement in VOC has been elucidated, less is known about the pathologic role of monocytes. Monocytes are of particular interest to VOC pathophysiology because they are especially malleable to inflammatory signaling. Indeed, inflammatory disease states such as COPD, obesity and atherosclerosis are known to influence monocyte development and alter monocyte subpopulations. Recently, nonclassical monocytes (CD14 dimCD16 +) with high heme oxygenase-1 expression have been shown to have a critical role in preventing VOC, generating renewed interest in monocytes as a therapeutic focus in SCD. In this study, we describe the monocyte subsets found in SCD patients during VOC by performing immunophenotypic flow cytometric, enzymatic, and morphologic analysis on peripheral blood obtained during hospitalization for VOC. Herein, we add to the growing body of evidence suggesting aberrant monocyte populations underpin VOC pathophysiology. We found that SCD monocytes during VOC possess an immature phenotype as demonstrated by 1) decreased CD4 positivity (p &amp;lt; .01), 2) low α-naphthyl butyrate esterase (ANBE) expression, and 3) naïve morphologic features (high nuclear/cytoplasmic ratio, indented or less lobular nuclei, and decreased cytoplasmic vacuolization). We additionally found an increase in CD14 +CD16 -CD4 - monocytes (p &amp;lt; .01), a subset associated with the impaired immune response of post-trauma patients. Interestingly, we also found a large proportion of CD14 +CD4 -HLA-DR - monocytes which, under normal circumstances, are exclusively found in neonates (p &amp;lt; .01). Finally, we report an increase in nonclassical monocytes (CD14 dimCD16 +), providing further evidence for the connection between this subset and the molecular mechanisms driving VOC. Taken together, these findings suggest that SCD patients in VOC deploy relatively immature monocytes that possess a lower capacity for antigen presentation, likely contributing to the immune dysfunction observed in SCD.

Stigma and patient-controlled analgesia: Trust is the essential ingredient of successful patient education in the patient-doctor relationship

A clinical decision report using: Van Beers EJ, Van Tuijn CFJ, Nieuwkerk PT, et al. Patient-controlled analgesia versus continuous infusion of morphine during vaso-occlusive crisis in sickle cell disease, a randomized controlled trial. Am J Hematol. 2007;82(11):955-960. https://doi.org/10.1002/ajh.20944 for a patient with recurrent vaso-occlusive crisis secondary to Sickle Cell Disease.