A systematic review of quality of life in sickle cell disease and thalassemia after stem cell transplant or gene therapy

Long-term quality of life after hematopoietic cell transplant for sickle cell disease in childhood: A STELLAR interim analysis

We prospectively collected PROMIS©25 and PROMIS©29 surveys in the Sickle Cell Transplant Evaluation of Long Term and Late Effects Registry (STELLAR). Mobility and social participation T-scores were decreased; all other domains were within the norm.

Assessing Psychosocial Risk and Resilience to Support Readiness for Gene Therapy in Sickle Cell Disease: A Consensus Statement

Importance

The introduction of gene therapies into the clinical care landscape for individuals living with sickle cell disease (SCD) represents a momentous achievement with the potential to rewrite the story of the world's most prevalent heritable blood disorder. This disease, which was first described in 1910 and did not see a US Food and Drug Administration-approved therapeutic until 1998, is poised to be among the first to realize the promise of gene therapy and genome editing. However, the future of these treatments now rests on how evidence of safety, outcomes, and acceptance in clinical practice unfolds in SCD. Furthermore, historic injustices involving the exploitation of individuals from minoritized racial and ethnic groups in medical contexts necessitate extreme care in ensuring readiness among individuals with SCD considering genetic therapies.

Objective

To address a gap in resources focused on patient readiness for gene therapy.

Evidence Review

The Cure Sickle Cell Initiative organized the Patient Readiness and Resilience Working Group in September 2020. Membership was comprised of behavioral health clinicians and scientists with expertise in SCD, adults with lived experience with SCD, and a caregiver. Over 2 years, the working group developed consensus recommendations and created resources to guide implementation of pregene therapy patient readiness assessments. Recommendations centered on strategies to enhance delivery of education about gene therapy and assess knowledge and understanding, interest and motivation, and psychosocial risk and resilience factors.

Findings

Five goals of a pregene therapy patient readiness assessment were identified: (1) gathering information about a patient's understanding of and perceived readiness for gene therapy; (2) encouraging an open dialogue; (3) providing a conceptualization of psychosocial factors that may influence participation in gene therapy; (4) identifying patient strengths that can be used to promote psychosocial well-being before, during, and after gene therapy; (5) identifying and addressing psychosocial risks.

Conclusions and Relevance

Patient readiness and psychosocial factors will have tangible implications for the success of gene therapy at individual and collective levels. Health care institutions, industry, payers, policymakers, and clinicians all shoulder responsibility for ensuring that patients with SCD are adequately prepared for gene therapy and supported in ways that optimize readiness and access. Resources described here may be leveraged as a guide to support implementation of pregene therapy assessments of patient readiness and resilience in SCD.

Longitudinal neurocognitive effects of nonmyeloablative hematopoietic stem cell transplant among older adolescents and adults with sickle cell disease: A description and comparison with sibling donors

Sickle cell disease (SCD) is associated with increased risk of neurocognitive deficits. However, whether functioning changes following nonmyeloablative hematopoietic stem cell transplant (HSCT) remains unclear. This study aimed to examine changes in neuropsychological functioning pre- to post-transplant among patients with SCD and compare patients and siblings. Adults with SCD (n = 47; Mage = 31.8 ± 8.9) and their sibling stem cell donors (n = 22; Mage = 30.5± 9.2) enrolled on a nonmyeloablative HCST protocol completed cognitive and patient-reported outcome assessments at baseline and 12 months post-transplant. Path analyses were used to assess associations between pre-transplant variables and sibling/patient group status and post-transplant function. Mean patient cognitive scores were average at both timepoints. Patient processing speed and somatic complaints improved from baseline to follow-up. Baseline performance predicted follow-up performance across cognitive variables; patient/sibling status predicted follow-up performance on some processing speed measures. Results suggest that patients with SCD demonstrate slower processing speed than siblings. Processing speed increased pre- to post-HSCT among patients and siblings, and on some measures patients demonstrated greater improvement. Thus, HSCT may improve processing speed in patients, although further confirmation is needed. Findings provide promising evidence that neurocognitive functioning remains stable without detrimental effects from pre- to 12-months post nonmyeloablative HSCT in individuals with SCD.

Factors Related to the Quality of Life in Children with Transfusion-Dependent Thalassemia

Objective: Increased survival rate of patients with Transfusion-dependent Thalassemia (TDT) should be in line with their good quality of life (QoL). The study aimed to analyze the relationship between sociodemographic factors and clinical characteristics with the QoL of children with TDT. Methods: A cross-sectional study was conducted at Hasan Sadikin General Hospital from December 2022 to February 2023. A total of 158 eligible subjects aged 5-18 years with TDT were included in the analysis. QoL assessment was performed using child self-report and parent-proxy report questionnaires, along with physical examination findings. Bivariate and multivariate analyses were conducted to analyze the data. Results: A total of 158 subjects who met the research criteria were included in the analysis. Of 58.9% of children with TDT had a low adherence rate to iron chelating therapy (ICT). School function had the lowest score in QoL based on child-self report and parent proxy. Gender (p<0,05) and adherence to ICT (p<0,05) were significantly associated with lower quality of life. Conclusion: Female and adherence to ICT were predictors of children with TDT's QoL.

Health-related quality of life with standard and curative therapies in thalassemia: A narrative literature review

Health-related quality of life (HRQOL) is a patient-reported outcome that assesses the impact of a disease or illness on different domains of a patient's life. Different general and disease-specific measures can be used to evaluate HRQOL. This article aimed to summarize the evidence for HRQOL among patients with transfusion-dependent (TDT) and non-transfusion-dependent thalassemia (NTDT). We included HRQOL data related to standard therapy with blood transfusions, iron chelation, and/or luspatercept in TDT and NTDT, as well as curative therapies for TDT, including hematopoietic stem cell transplant (HSCT) and gene therapy. Patients with thalassemia had worse HRQOL scores compared to the general population, and chronic pain was seen to increase in frequency and severity over time with age. NTDT patients reported worse physical health and functioning, mental health, general health, and vitality than TDT patients. However, TDT patients reported worse pain, change in health, and social support than NTDT. Most therapies improved overall HRQOL among thalassemia patients. Deferasirox, an oral iron chelator, was associated with more HRQOL benefits compared to deferoxamine, an intravenous iron chelator. Luspatercept showed clinically meaningful improvement in physical functioning among TDT and NTDT. Furthermore, HSCT and gene therapy were associated with better physical, emotional, and mental domains scores.

A systematic review comparing allogeneic hematopoietic stem cell transplant to gene therapy in sickle cell disease

INTRODUCTION

Allogeneic hematopoietic stem cell transplant (HSCT) and gene therapy (GT) are two potentially curative approaches for sickle cell disease (SCD), but they have never been compared in clinical trials.

OBJECTIVE

To compare the safety and efficacy of HSCT and GT to assist clinicians and patients in making informed treatment decisions.

METHODS

Phase I-III clinical trials and case reports/series were included. Regimens included HSCT from all stem cell sources, lentiviral gene therapy, and gene editing, with any conditioning regimen. We searched Medline and EMBASE databases as of 1st June 2020 for studies reporting HSCT and GT outcomes in SCD. The Newcastle-Ottawa scale was used to assess the risk of bias. Descriptive statistics and post-hoc imputation for standard deviations of mean change in FEV1 and FVC were performed.

RESULTS

In total, 56 studies (HSCT, n = 53; GT, n = 3) representing 1,198 patients met inclusion criteria (HSCT, n = 1,158; GT, n = 40). Length of follow-up was 3,881.5 and 58.7 patient-years for HSCT and GT, respectively. Overall quality of evidence was low, with no randomized controlled trials identified. Two-year overall survival for HSCT was 91%; mortality was 2.5% for GT. Acute chest syndrome and vaso-occlusive episodes were reduced post-HSCT and GT. Meta-analysis was not possible due to lack of comparator and heterogeneity in outcome measures reporting. Very few studies reported post-transplant end-organ function. Six secondary malignancies (5 post-HSCT, 1 post-GT) were reported.

DISCUSSION

Reporting of SCD-related complications and patient-important outcomes is lacking for both strategies. We advocate for standardized reporting to better compare outcomes within and between treatment groups.

Health-Related Quality-of-Life Profile of Pediatric Patients with β Thalassemia after Hematopoietic Stem Cell Transplantation

Matched hematopoietic stem cell transplantation (HSCT) is a feasible and curative treatment in pediatric patients with beta thalassemia major (β-TM). However, little data are available regarding patients and their parents' health-related quality of life (HRQoL) after the procedure. As such, we investigated the HRQoL of pediatric patients with β-TM after HSCT compared to that of patients treated with blood transfusions and iron chelation. The health-related quality of life of 43 β-TM pediatric patients and 43 parents were evaluated using the Pediatric Quality of Life Inventory (PedsQL). A total of 25 patients underwent HSCT: 15 from a sibling and 10 from an HLA-matched donor. The median follow-up time from HSCT was 5 years (range 1-13 years). The mean ages at the survey were 10.1 years (range 5-15) and 9.6 years (range 5-15) for transfused and transplanted patients, respectively. A significant reduction in HRQoL was reported in the group of transfused patients compared with that of patients transplanted in the following PedsQL domains: children's and parents' physical functions, Δ = -15.4, p = 0.009 and Δ = -11.3, p = 0.002, respectively; children's and parents' emotional functioning, Δ = -15.2, p = 0.026 and Δ = -15.2, p = 0.045, respectively; child's and parents' school functioning, Δ = -25, p = 0.005 and Δ = -22.5, p = 0.011, respectively; total child and parents scores, Δ = -14.5, p = 0.004 and Δ = -13.2, p = 0.005, respectively. The results of a multivariable analysis showed that the HSCT procedure was significantly associated with a higher total child PedsQL score (adjusted mean difference = 15.3, p = 0.001) and a higher total parent PedsQL score (adjusted mean difference = 14.1, p = 0.006). We found no significant difference in the HRQoL measured after sibling or unrelated human leukocyte antigen (HLA)-matched HSCT. Finally, a significant positive correlation across all the PedsQL domains was found between the scores reported by the children and those reported by their parents. In conclusion, our study shows that HSCT in pediatric patients with β-TM is associated with a good overall HRQoL profile. This information further supports physicians when counseling patients and their parents before the HSCT procedure.

Thalassemia patients in transfussion dependent period and after hematopoietic stem cell transplantation: how are the psychiatric status and life quality of these patients?

Although hematopoietic stem cell transplantation (HSCT) has been widely used to treat patients with beta-thalassemia major, evidence showing whether this treatment improves mental health, self esteem and health-related quality of life (HRQoL) is limited. We aimed to describe psychiatric problems, HRQoL and self-esteem scores of patients who have thalassemia and compared with patients who underwent HSCT in the current study. A total of 24 patients with thalassemia major and 13 patients who underwent HSCT at least 2 years ago aged between 7-37 years were included. We used The Children's Depression Inventory, The Spielberger State-Trait Anxiety Inventory, and Pediatric Quality of LifeTM (PedsQL™) for assesment of children and Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), World Health Organization Quality of Life Scale Brief Version (WHOQOL-BREF) for assessment of adults. We also used Piers Harris Self Concept Scale for children and adults. Psychopathologies are common in both groups (50% in Thalassemia group and 69.2% in HSCT group). Popularity scores in Piers Haris scale of patients in HSCT group were significantly higher compared to thalassemia group (p = 0.03). Additionally, HSCT group had higher scores in physical health subscales of HRQoL in both children and parents'(p = 0.02, p = 0.03 respectively). Our findings suggest improved HRQoL and self-esteem in thalassemia patients after HSCT. However, due to the high prevalence of mental disorders in both groups, we would like to emphasize that clinicians should examine not only the physical but also the psychological state of the patients with thalessemia during the their treatment and follow-up period after HSCT.

Gut microbiota and metabolites drive chronic sickle cell disease pain

Pain is a debilitating symptom and leading reason for hospitalization of individuals with sickle cell disease. Chronic sickle cell pain is poorly managed because the biological basis is not fully understood. Using transgenic sickle cell mice and fecal material transplant, we determined that the gut microbiome drives persistent sickle cell pain. In parallel patient and mouse analyses, we identified bilirubin as one metabolite that induces sickle cell pain by altering vagus nerve activity. Furthermore, we determined that decreased abundance of the gut bacteria Akkermansia mucinophila is a critical driver of chronic sickle cell pain. These experiments demonstrate that the sickle cell gut microbiome drives chronic widespread pain and identify bacterial species and metabolites that should be targeted for chronic sickle cell disease pain management.

Physical, Mental, and Social Health of Adult Patients with Sickle Cell Disease after Allogeneic Hematopoietic Stem Cell Transplantation: A Mixed-Methods Study

Patients with sickle cell disease (SCD) experience a considerable physical and psychosocial disease burden. In recent years, the application of allogeneic hematopoietic stem cell transplantation (HSCT) to treat adults with SCD has increased. A thorough understanding of patients' physical, mental, and social health before and after cure is needed to meet the needs of this growing group of patients. We aimed to explore the perspectives of adult SCD patients on the changes in their experienced health and personal life goals after being cured. A mixed-methods approach was used, comprising a semistructured interview and a set of 9 Patient Reported Outcomes Measurement Information System (PROMIS) measures. Adult SCD patients who underwent HSCT at least 1 year earlier were eligible to participate in the study. Interviews were thematically analyzed using MAXQDA software. PROMIS T scores were compared with reference scores of the general population using SPSS Statistics. Ten patients participated in the study; their median age was 29.5 years (range, 19 to 49 years), and their median time since HSCT was 2.7 years (range, 1.0 to 3.5 years). Themes from the interviews were (1) pain/living pain free, (2) physical well-being, (3) mental well-being, (4) perspective/ outlook, (5) education/work, (6) family/friends, and (7) activities/participation. Following the PROMIS framework, we described these themes in a narrative synthesis according to health domain and categorized in 4 chronological time phases: before HSCT, first year post-transplantation, current situation, and future expectations. Physical health improved greatly, but transplantation-related toxicity, ongoing pain from avascular osteonecrosis, and fatigue negatively impacted quality of life in some patients. Furthermore, emotional struggles during the post-transplantation period were common, and patients expressed a need for psychological help. Patients reported improvements in social health and the ability to pursue personal life goals. The mean T scores of all PROMIS measures fell within the normal symptom limits compared with reference data of the general population, although, large variations were observed among the participants, matching our qualitative findings. In general, adult SCD patients experienced improved physical, mental, and social health after cure by HSCT and were able to pursue personal life goals. Yet they found themselves confronted with a new and unfamiliar reality that brought different challenges. Pain due to irreversible avascular osteonecrosis continued to have a negative impact. Clinicians should aim to help patients have realistic expectations before transplantation and offer timely psychological care.

Sense of coherence or self-efficacy as predictors of health-related quality of life in sickle cell disease patients

Patients with sickle cell disease (SCD) suffer from impaired health-related quality of life (HRQoL). This study aimed to determine the level of HRQoL, sense of coherence (SOC), and self-efficacy (SE) in a sample of SCD patients, and to explore predictors of their physical and mental HRQoL. A cross-sectional descriptive study was conducted on 83 SCD patients of one university hospital. The data of the study was collected through Persian versions of the Short-Form Health Survey SF-36 (RAND 36-item), the Sense of Coherence Scale (SOC-13), and the Sickle Cell Self-Efficacy Scale (SCSES). The mean age of the patients was 26.34 ± 8.19 years old. Patients' mean scores for the Physical Component Summary (PCS), Mental Component Summary (MCS), SOC, and SCSES were 40.57 ± 17.18 (range: 0-100), 50.44 ± 17.95 (range: 0-100), 52.40 ± 15.35 (range: 13-91), 26.40 ± 6.96 (range: 9-45), respectively. Regression models showed that the level of the patients' SOC, was the main predictor of the MCS (β = 0.37, p < 0.001). However, the level of the patients' SE was the main predictor of the PCS (β = 0.30, p = 0.004). Also, "blood transfusion history" in patients was a common predictor for both the PCS (β =  - 0.28, p = 0.008) and the MCS (β =  - 0.29, p = 0.003). These results can assist nurses and clinicians to plan clinical interventions for SCD patients by focusing on increasing the level of the SOC and SE and improving SCD patients' HRQoL. Furthermore, measuring the level of the SOC and self-efficacy as screening tests are useful to find patients with a greater risk of impaired HRQoL.

Multimodal phenotyping and correlates of pain following hematopoietic cell transplant in children with sickle cell disease

INTRODUCTION

There is limited understanding of pain, patient-reported outcomes (PROs) of health-related quality of life (HRQoL), psychological factors, and experimental pain sensitivity before and following hematopoietic cell transplant (HCT) in children with sickle cell disease (SCD).

METHODS

Individuals aged 8 years and older, English speaking, and scheduled for a HCT were invited to participate in an observational study where they completed assessments of pain, PROs, psychological factors, and qualitative interviews before and around 3 months, 6 months, 1 year, and 2 years post-HCT. An optional substudy of experimental pain sensitivity before and around 6 month, 1 year, and 2 years post-HCT was also offered.

RESULTS

Data from eight participants (median age 13.5 years, 25% female) with sickle cell anemia (SCA) or similarly severe genotype, and successful donor-derived erythropoiesis post-HCT are reported. We found that collection of pain, PROs, psychological factors, and qualitative data were feasible in the context of HCT. We found moderate to large differences in pain and some PROs between baseline to 1 year and baseline to 2 year post-HCT based on effect sizes, but only some differences were statistically significant. We found moderate to large differences in pressure pain threshold and moderate differences in cold pain threshold between baseline to 1 year and baseline to 2 year post-HCT based on effect sizes, but these differences were not statistically significant. Qualitative data indicated an improvement in pain and HRQoL post-HCT.

CONCLUSION

This study provides a framework for the conduct of multimodal pain assessments before and after HCT, which is feasible but faced with unique barriers.

Global perspectives on cellular therapy for children with sickle cell disease

PURPOSE OF REVIEW

Low-income and middle-income countries (LMICs), primarily in sub-Saharan Africa (SSA), predominantly experience the burden of sickle cell disease (SCD). High frequency of acute and chronic complications leads to increased utilization of healthcare, which burdens fragile health systems. Mortality for children with limited healthcare access remains alarmingly high. Cellular based therapies such as allogeneic hematopoietic stem cell transplant (HSCT) are increasingly used in resource-rich settings as curative therapy for SCD. Broad access to curative therapies for SCD in SSA would dramatically alter the global impact of the disease.

RECENT FINDINGS

Currently, application of cellular based therapies in LMICs is limited by cost, personnel, and availability of HSCT-specific technologies and supportive care. Despite the challenges, HSCT for SCD is moving forward in LMICs. Highly anticipated gene modification therapies have recently proven well tolerated and feasible in clinical trials in resource-rich countries, but access remains extremely limited.

SUMMARY

Translation of curative cellular based therapies for SCD should be prioritized to LMICs where the disease burden and cost of noncurative treatments is high, and long-term quality of life is poor. Focus on thoughtful modifications of current and future therapies to meet the need in LMICs, especially in SSA, will be especially impactful.

Neuropsychological, behavioral, and quality-of-life outcomes in children and adolescents with sickle cell disease treated with nonmyeloablative matched sibling donor hematopoietic cell transplantation: A case series

BACKGROUND/OBJECTIVES

Despite advances in the treatment of sickle cell disease (SCD), cerebrovascular and cognitive insults can have lifelong consequences. Hematopoietic cell transplantation (HCT) is an established curative therapy, and recent studies have demonstrated efficacy with reduced toxicity nonmyeloablative (NMA) regimens, but little is known about neuropsychological outcomes. The objective of this study was to describe neuropsychological, behavioral, and quality-of-life outcomes with medical correlates in children with SCD who received an NMA matched sibling donor (MSD) HCT.

DESIGN/METHODS

Retrospective cohort analysis of nine recipients with hemoglobin SS SCD who underwent MSD HCT using the National Institutes of Health (NIH) NMA protocol.

RESULTS

Mean full-scale intellectual functioning (FSIQ) was average pre-HCT (FSIQ = 92.1, SD 9.0; n = 8) and 2 years post-HCT (mean FSIQ = 96.6; SD 11.1; N = 9). Neuropsychological functioning was largely average across all cognitive domains, and no pre/post-HCT differences were found to be statistically significant given the small sample size. However, effect sizes revealed moderate improvements in processing speed (Cohen's d = .72) and verbal memory (Cohen's d = .60) post-HCT, and declines in measures of attention (Cohen's d = -.54) and fine motor speed and dexterity (Cohen's d = -.94). Parents endorsed better quality of life (Cohen's d = .91), less impact of SCD on their family, and less worry about their child's future (Cohen's d = 1.44).

CONCLUSION

Neuropsychological functioning in a sample of children and adolescents treated uniformly with NMA MSD HCT remained stable or improved in most cognitive domains, and improvements in quality of life and family functioning were observed.

ADaPTS "(AD)olescents (P)ath through (T)ransplant (S)ickle cell disease"

Background

Sickle cell disease is an inherited chronic hematological disorder with an average lifespan of fifty years. The human cost of sickle cell disease includes missed school days, occupational opportunities, social isolation, stigmatization, and psychological sequelae. Hematopoietic cell transplantation (HCT) is the only curative therapy available but comes with potential morbidity and mortality. Our study explores how quality of life (QoL) is affected from the perspective of an adolescent who has undergone a nonmyeloablative matched sibling donor HCT.

Methods

We employed multiple case study methodology with purposeful sampling by selecting information-rich cases. Data sources: 1) QoL inventories 2) patient interviews 3) parent interview 4) vital support interview 5) medical record analysis. Data analysis: Intra-case analysis by assembling evidence within a single case and then analyzing the differences within cases to create a rich case description. Next, a time series analysis was completed to track changes in patients’ QoL. We used multiple sources of data to compose a timeline and changes across time. Then, we employed pattern matching as an analytical technique allowing for examination of patterns across cases. Finally, we used cross case synthesis to review results of each case.

Results

Quality of life was reported across the physical, social and psychological domains for 5 participants. All had sickle cell HgSS genotype, 80% were male and 80% were born outside of Canada. Physical domain: pre-transplant, 100% of patients experienced pain, and the majority suffered from fatigue, insomnia, and fevers resulting in hospitalizations. Afterwards, participants reported improved physical wellbeing. Social domain: pre-transplant, QoL was poor characterized by stigma, social isolation, and parental absenteeism. Post-HSCT adolescents gained social acceptance in areas that had stigmatized and excluded them. They were able to participate freely in activities with peers and their social life vastly improved. Psychological pre-transplant life experiences were overshadowed by psychological stress. The majority commented that their future was bleak and may lead to premature death. Afterwards adolescents described a crisis free life with positive psychological outcomes.

Conclusions

Adolescents with sickle cell disease who undertook HCT demonstrated improved QoL one year post transplant with regard to physical, social and psychological well-being.

Sickle Cell Transplantation Evaluation of Long-term and Late Effects Registry (STELLAR) to Compare Long-term Outcomes After Hematopoietic Cell Transplantation to Those in Siblings Without Sickle Cell Disease and in Nontransplanted Individuals With Sickle Cell Disease: Design and Feasibility Study

BACKGROUND

There are sparse data on the long-term and late effects of hematopoietic cell transplantation (HCT) for sickle cell disease (SCD).

OBJECTIVE

This study aims to establish an international registry of long-term outcomes post-HCT for SCD and demonstrate the feasibility of recruitment at a single site in the United States.

METHODS

The Sickle Cell Transplantation Evaluation of Long-Term and Late Effects Registry (STELLAR) was designed to enroll patients with SCD ≥1 year post-HCT, their siblings without SCD, and nontransplanted controls with SCD to collect web-based participant self-reports of health status and practices by using the Bone Marrow Transplant Survivor Study (BMTSS) surveys, health-related quality of life (HRQOL) using the Patient-Reported Outcomes Measurement Information System (PROMIS) Pediatric Profile-25 or Pediatric Profile-29 survey, chronic graft-versus-host disease (cGVHD) using the symptom scale survey, daily pain using an electronic pain diary, the economic impact of HCT using the financial hardship survey, sexual function using the PROMIS Sexual Function SexFSv2.0 survey, and economic productivity using the American Time Use Survey (ATUS). We also piloted retrieval of clinical data previously submitted to the Center for International Blood and Marrow Transplant Research (CIBMTR); recorded demographics, height, weight, blood pressure, waist and hip circumferences, timed up and go (TUG) test, and handgrip test; and obtained blood for metabolic screening, gonadal function, fertility potential, and biorepository of plasma, serum, RNA, and DNA.

RESULTS

Of 100 eligible post-HCT patients, we enrolled 72 (72%) participants aged 9-38 (median 17) years. We also enrolled 19 siblings aged 5-32 (median 10) years and 28 nontransplanted controls with SCD aged 4-46 (median 22) years. Of the total 119 participants, 73 (61%) completed 85 sets of surveys and 41 (35%) contributed samples to the biorepository. We completed ATUS interviews of 28 (24%) participants. We successfully piloted retrieval of data submitted to the CIBMTR and expanded recruitment to multiple sites in the United States, Canada, the United Kingdom, and Nigeria.

CONCLUSIONS

It is feasible to recruit subjects and conduct study procedures for STELLAR in order to determine the long-term and late effects of HCT for SCD.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/36780.

Adherence to Iron Chelation Therapy among Adults with Thalassemia: A Systematic Review

Iron chelation therapy (ICT) is essential to prevent complications of iron overload in patients with transfusion-dependent thalassemia. However, the role that adherence to ICT plays in health-related outcomes is less well known. Our objectives were to identify adherence rates of ICT, and to assess methods of measurement, predictors of adherence, and adherence-related health outcomes in the literature published between 1980 and 2020. Of 543 articles, 43 met the inclusion criteria. Studies measured ICT adherence, predictors, and/or outcomes associated with adherence. Most studies were across multiple countries in Europe and North America (n = 8/43, 18.6%), recruited in clinics (n = 39/43, 90.7%), and focused on β-thalassemia (β-thal) (n = 25/43, 58.1%). Common methods of assessing ICT adherence included patient self-report (n = 24/43, 55.8%), pill count (n = 9/43, 20.9%), prescription refill history (n = 3/43, 7.0%), provider scoring (n = 3/43, 7.0%), and combinations of methods (n = 4/43, 9.3%). Studies reported adherence either in 'categories' with different levels of adherence (n = 24) or 'quantitatively' as a percentage of doses of medication taken out of those prescribed (n = 17). Adherence levels varied (median 91.7%, range 42.0-99.97%). Studies varied in sample size and methods of adherence assessment and reporting, which prohibited meta-analysis. Due to a lack of consensus on how adherence is defined, it is difficult to compare ICT adherence reporting. Further research is needed to establish guidelines for assessing adherence and identifying suboptimal adherence. Behavioral digital interventions have the potential to optimize ICT adherence and health outcomes.

In Vitro and In Vivo Studies for the Investigation of γ-Globin Gene Induction by Adhatoda vasica: A Pre-Clinical Study of HbF Inducers for β-Thalassemia

Fetal hemoglobin (HbF) is a potent genetic modifier, and the γ-globin gene induction has proven to be a sustainable therapeutic approach for the management of β-thalassemia. In this study, we have evaluated the HbF induction ability of A. vasica in vitro and in vivo, and the identification of potential therapeutic compounds through a bioassay-guided approach. In vitro benzidine-Hb assay demonstrated strong erythroid differentiation of K562 cells by A. vasica extracts. Subsequently, an in vivo study with an aqueous extract of A. vasica (100 mg/kg) showed significant induction of the γ-globin gene and HbF production. While in the acute study, the hematological and biochemical indices were found to be unaltered at the lower dose of A. vasica. Following the bioassay-guided approach, two isolated compounds, vasicinol (1) and vasicine (2) strongly enhanced HbF levels and showed prominent cellular growth kinetics with ample accumulation of total hemoglobin in K562 cultures. High HbF levels were examined by immunofluorescence and flow cytometry analysis, concomitant with the overexpression in the γ-globin gene level. Compound 1 (0.1 µM) and compound 2 (1 µM) resulted in a greater increase in F-cells (90 and 83%) with marked up (8-fold and 5.1-fold) expression of the γ-globin gene, respectively. Molecular docking studies indicated strong binding affinities of (1) and (2) with HDAC2 and KDM1 protein that predict the possible mechanism of compounds in inhibition of these epigenetic regulators in the γ-globin gene reactivation. Altogether, these observations demonstrated the therapeutic usefulness of A. vasica for fostering HbF production in clinical implications for blood disorders.

Significant improvement of child physical and emotional functioning after familial haploidentical stem cell transplant

Allogeneic stem cell transplantation (AlloSCT) represents the only curative therapy for sickle cell disease (SCD). However, limited availability of matched related donors and suboptimal outcomes following AlloSCT with unrelated donors has led to investigation of alternative donors. Among children with high-risk SCD, we evaluated health-related quality of life (HRQoL) impact in the two years following familial haploidentical SCT. HRQoL was collected from parent and child raters, using the Child Health Ratings Inventories Generic measure and haploidentical SCT-specific module. Repeated measures models were fit to assess HRQoL changes over time and by rater. Nineteen children (mean age 12.9 yrs [standard deviation, 5.3]; 63% male) and their parents were included. There were no differences in the 2-yr trajectories of child physical or emotional functioning (EF) by rater. Child physical functioning and EF scores were significantly lower at day +45 than baseline, but scores recovered by day +180. There was significant improvement in EF (p = 0.03) at 2 yrs vs baseline. A similar pattern of scores over time was seen for parent ratings of child's global HRQoL. Despite treatment intensity in the initial months following AlloSCT, patient scores recovered or exceeded baseline scores at two years. This trial is registered at clinicaltrials.gov (NCT01461837).

Heterogeneity of the long-term economic burden of severe sickle cell disease: a 5-year longitudinal analysis

BACKGROUND

Sickle cell disease (SCD) is a lifelong burdensome disorder of heterogenic expression. This study investigated the longer-term economic burden of severe presentation of SCD. As SCD treatment landscapes evolve toward curative intent gene therapies, understanding how SCD-associated costs may change over the patient lifetime will be important for medical decision-making.

METHODS

Patients with severe presentation of SCD (presence of acute vaso-occlusive events [VOEs] or history of stroke and/or other disease-related sequelae), were identified within the MarketScan Commercial and Medicare Supplemental and Multi-state Medicaid Databases from 1/1/2010 to 12/31/2018. The first SCD claim served as the index date and patients were followed over a 5-year post-period. Clinical characteristics and healthcare resource utilization and costs were assessed over follow-up for eligible cohorts of commercial and Medicaid patients with severe SCD presentation and age-based subgroups (<18, 18-30, and ≥31).

RESULTS

A total of 4,487 patients, primarily insured via Medicaid (79.2%), qualified for the analysis. Patients evidenced persistent VOEs over follow-up; prevalence of most comorbidities increased with age. Mean total healthcare costs over the 5-year follow-up were $275,143 (SD± $406,770) and $362,728 (SD± $620,189) in the commercial and Medicaid samples, respectively. Disease severity, assessed by the number of VOEs and utilization of inpatient and emergency services, peaked in the 18-30 year group in both samples. These groups also evidenced the highest mean healthcare costs over the 5-year follow-up at $344,776 (SD± $434,521) and $671,321 (SD± $938,764) in the commercial and Medicaid samples respectively.

CONCLUSION

Results indicate high clinical need and economic burden among patients with severe presentation of SCD. These findings not only highlight the need for improved therapeutic options to limit or prevent disease progression, but also start to provide insight on lifetime costs of SCD that will be needed in the evaluation of emerging curative intent therapies.

OUP accepted manuscript

Beta-thalassemia is one of the most common monogenic disorders. Standard treatment of the most severe forms, i.e., transfusion-dependent thalassemia (TDT) with long-term transfusion and iron chelation, represents a considerable medical, psychological, and economic burden. Allogeneic hematopoietic stem cell transplantation from an HLA-identical donor is a curative treatment with excellent results in children. Recently, several gene therapy approaches were evaluated in academia or industry-sponsored clinical trials as alternative curative options for children and young adults without an HLA-identical donor. Gene therapy by addition of a functional beta-globin gene using self-inactivating lentiviral vectors in autologous stem cells resulted in transfusion independence for a majority of TDT patients across different age groups and genotypes, with a current follow-up of multiple years. More recently, promising results were reported in TDT patients treated with autologous hematopoietic stem cells edited with the clustered regularly interspaced short palindromic repeats-Cas9 technology targeting erythroid BCL11A expression, a key regulator of the normal switch from fetal to adult globin production. Patients achieved high levels of fetal hemoglobin allowing for discontinuation of transfusions. Despite remarkable clinical efficacy, 2 major hurdles to gene therapy access for TDT patients materialized in 2021: (1) a risk of secondary hematological malignancies that is complex and multifactorial in origin and not limited to the risk of insertional mutagenesis, (2) the cost—even in high-income countries—is leading to the arrest of commercialization in Europe of the first gene therapy medicinal product indicated for TDT despite conditional approval by the European Medicines Agency.

Evidence-Based Minireview: In young children with severe sickle cell disease, do the benefits of HLA-identical sibling donor HCT outweigh the risks?

In case 1, a 14-month-old male child with sickle cell disease (SCD) was referred for evaluation for an allogeneic hematopoietic stem cell transplant (HCT). The patient had a history of dactylitis 3 times in his first year of life and febrile episodes twice at the consult. His 4-year-old sister was found to be human leukocyte antigen (HLA) identical. The patient was started on hydroxyurea (HU) at 2.5 years of age. His parents again sought consultation when he was 5 years old because of concerns about his medical condition. At the time, the patient had experienced 2 vaso-occlusive pain episodes (VOEs) requiring hospitalization during the previous 2 years. He had also experienced intermittent pain crises requiring rest at home for 2 to 3 days. The child has not attended school in person due to the COVID-19 pandemic. The family is considering HCT but is ambivalent about it because of potential toxicity. In case 2, an 8-year-old female child is 3 years out from HCT for SCD from her HLA-identical sibling. Before HCT, despite receiving HU, she had experienced >5 VOEs requiring hospitalization and 2 episodes of acute chest syndromes in the previous 3 years. She had also been missing almost 50 days of school days each year. After HCT, she is now attending school regularly and participating in all normal age-appropriate activities. The parents believe that HCT has been transformative in their child's life.

Hematopoietic cell transplantation for sickle cell disease: updates and future directions

Excellent outcomes in hematopoietic cell transplantation (HCT) from HLA-identical siblings, improvements in conditioning regimens, novel graft-versus-host disease prophylaxis, and the availability of alternative donors have all contributed to the increased applicability and acceptability of HCT for sickle cell disease (SCD). In young children with symptomatic SCD with an available HLA-identical related donor, HCT should be carefully considered. HCT from alternative donors is typically undertaken only in patients with severe symptoms, causing or likely to cause organ damage, and in the context of clinical trials. Patients undergoing HCT for SCD require careful counseling and preparation. They require careful monitoring of unique organ toxicities and complications during HCT. Patients must be prospectively followed for a prolonged time to determine the long-term outcomes and late effects of HCT for SCD. Thus, there is a need for a universal, longitudinal clinical registry to follow patients after HCT for SCD in conjunction with individuals who do not receive HCT to compare outcomes. Antibody-based conditioning and ex-vivo umbilical cord blood expansion are likely to improve the availability and acceptability of HCT. In addition, new disease-modifying drugs and the emerging option of the autologous transplantation of gene-modified hematopoietic progenitor cells are likely to expand the available therapeutic options and make decision-making by patients, physicians, and caregivers even more complicated. Future efforts must also focus on determining the impact of socioeconomic status on access to and outcomes of HCT and the long-term impact of HCT on patients, families, and society.

Editing outside the body: Ex vivo gene-modification for β-hemoglobinopathy cellular therapy

Genome editing produces genetic modifications in somatic cells, offering novel curative possibilities for sickle cell disease and β-thalassemia. These opportunities leverage clinical knowledge of hematopoietic stem cell transplant and gene transfer. Advantages to this mode of ex vivo therapy include locus-specific alteration of patient hematopoietic stem cell genomes, lack of allogeneic immune response, and avoidance of insertional mutagenesis. Despite exciting progress, many aspects of this approach remain to be optimized for ideal clinical implementation, including the efficiency and specificity of gene modification, delivery to hematopoietic stem cells, and robust and nontoxic engraftment of gene-modified cells. This review highlights genome editing as compared to other genetic therapies, the differences between editing strategies, and the clinical prospects and challenges of implementing genome editing as a novel treatment. As the world's most common monogenic disorders, the β-hemoglobinopathies are at the forefront of bringing genome editing to the clinic and hold promise for molecular medicine to address human disease at its root.

2021 update on clinical trials in β-thalassemia

The treatment landscape for patients with β-thalassemia is witnessing a swift evolution, yet several unmet needs continue to persist. Patients with transfusion-dependent β-thalassemia (TDT) primarily rely on regular transfusion and iron chelation therapy, which can be associated with considerable treatment burden and cost. Patients with non-transfusion-dependent β-thalassemia (NTDT) are also at risk of significant morbidity due to the underlying anemia and iron overload, but treatment options in this patient subgroup are limited. In this review, we provide updates on clinical trials of novel therapies targeting the underlying pathology in β-thalassemia, including the α/non-α-globin chain imbalance, ineffective erythropoiesis, and iron dysregulation.

A Decision Support Tool for Allogeneic Hematopoietic Stem Cell Transplantation for Children With Sickle Cell Disease: Acceptability and Usability Study

Background

Individuals living with sickle cell disease (SCD) may benefit from a variety of disease-modifying therapies, including hydroxyurea, voxelotor, crizanlizumab, L-glutamine, and chronic blood transfusions. However, allogeneic hematopoietic stem cell transplantation (HCT) remains the only nonexperimental treatment with curative intent. As HCT outcomes can be influenced by the complex interaction of several risk factors, HCT can be a difficult decision for health care providers to make for their patients with SCD.

Objective

The aim of this study is to determine the acceptability and usability of a prototype decision support tool for health care providers in decision-making about HCT for SCD, together with patients and their families.

Methods

On the basis of published transplant registry data, we developed the Sickle Options Decision Support Tool for Children, which provides health care providers with personalized transplant survival and risk estimates for their patients to help them make informed decisions regarding their patients’ management of SCD. To evaluate the tool for its acceptability and usability, we conducted beta tests of the tool and surveys with physicians using the Ottawa Decision Support Framework and mobile health app usability questionnaire, respectively.

Results

According to the mobile health app usability questionnaire survey findings, the overall usability of the tool was high (mean 6.15, SD 0.79; range 4.2-7). According to the Ottawa Decision Support Framework survey findings, acceptability of the presentation of information on the decision support tool was also high (mean 2.94, SD 0.63; range 2-4), but the acceptability regarding the amount of information was mixed (mean 2.59, SD 0.5; range 2-3). Most participants expressed that they would use the tool in their own patient consults (13/15, 87%) and suggested that the tool would ease the decision-making process regarding HCT (8/9, 89%). The 4 major emergent themes from the qualitative analysis of participant beta tests include user interface, data content, usefulness during a patient consult, and potential for a patient-focused decision aid. Most participants supported the idea of a patient-focused decision aid but recommended that it should include more background on HCT and a simplification of medical terminology.

Conclusions

We report the development, acceptability, and usability of a prototype decision support tool app to provide individualized risk and survival estimates to patients interested in HCT in a patient consultation setting. We propose to finalize the tool by validating predictive analytics using a large data set of patients with SCD who have undergone HCT. Such a tool may be useful in promoting physician-patient collaboration in making shared decisions regarding HCT for SCD. Further incorporation of patient-specific measures, including the HCT comorbidity index and the quality of life after transplant, may improve the applicability of the decision support tool in a health care setting.

The Future of Gene Therapy for Transfusion-Dependent Beta-Thalassemia: The Power of the Lentiviral Vector for Genetically Modified Hematopoietic Stem Cells

β-thalassemia, a disease that results from defects in β-globin synthesis, leads to an imbalance of β- and α-globin chains and an excess of α chains. Defective erythroid maturation, ineffective erythropoiesis, and shortened red blood cell survival are commonly observed in most β-thalassemia patients. In severe cases, blood transfusion is considered as a mainstay therapy; however, regular blood transfusions result in chronic iron overload with life-threatening complications, e.g., endocrine dysfunction, cardiomyopathy, liver disease, and ultimately premature death. Therefore, transplantation of healthy hematopoietic stem cells (HSCs) is considered an alternative treatment. Patients with a compatible human leukocyte antigen (HLA) matched donor can be cured by allogeneic HSC transplantation. However, some recipients faced a high risk of morbidity/mortality due to graft versus host disease or graft failure, while a majority of patients do not have such HLA match-related donors. Currently, the infusion of autologous HSCs modified with a lentiviral vector expressing the β-globin gene into the erythroid progenitors of the patient is a promising approach to completely cure β-thalassemia. Here, we discuss a history of β-thalassemia treatments and limitations, in particular the development of β-globin lentiviral vectors, with emphasis on clinical applications and future perspectives in a new era of medicine.

Improving outcomes and quality of life for patients with transfusion-dependent β-thalassemia: recommendations for best clinical practice and the use of novel treatment strategies

INTRODUCTION

β-thalassemia is one of the most common inherited monogenic diseases. Many patients are dependent on a lifetime of red blood cell (RBC) transfusions and iron chelation therapy. Although treatments have a significant impact on quality of life (QoL), life expectancy, and long-term health outcomes have improved in recent decades through safer RBC transfusion practices and better iron chelation strategies. Advances in the understanding of the pathology of β-thalassemia have led to the development of new treatment options that have the potential to reduce the RBC transfusion burden in patients with transfusion-dependent (TD) β-thalassemia and improve QoL.

AREAS COVERED

This review provides an overview of currently available treatments for patients with TD β-thalassemia, highlighting QoL issues, and providing an update on current clinical experience plus important practical points for two new treatments available for TD β-thalassemia: betibeglogene autotemcel (beti-cel) gene therapy and the erythroid maturation agent luspatercept, an activin ligand trap.

EXPERT OPINION

Approved therapies, including curative gene therapies and supportive treatments such as luspatercept, have the potential to reduce RBC transfusion burden, and improve clinical outcomes and QoL in patients with TD β-thalassemia. Cost of treatment is, however, likely to be a significant barrier for payors and patients.

Cell and Gene Therapy for Anemia: Hematopoietic Stem Cells and Gene Editing

Hereditary anemia has various manifestations, such as sickle cell disease (SCD), Fanconi anemia, glucose-6-phosphate dehydrogenase deficiency (G6PDD), and thalassemia. The available management strategies for these disorders are still unsatisfactory and do not eliminate the main causes. As genetic aberrations are the main causes of all forms of hereditary anemia, the optimal approach involves repairing the defective gene, possibly through the transplantation of normal hematopoietic stem cells (HSCs) from a normal matching donor or through gene therapy approaches (either in vivo or ex vivo) to correct the patient’s HSCs. To clearly illustrate the importance of cell and gene therapy in hereditary anemia, this paper provides a review of the genetic aberration, epidemiology, clinical features, current management, and cell and gene therapy endeavors related to SCD, thalassemia, Fanconi anemia, and G6PDD. Moreover, we expound the future research direction of HSC derivation from induced pluripotent stem cells (iPSCs), strategies to edit HSCs, gene therapy risk mitigation, and their clinical perspectives. In conclusion, gene-corrected hematopoietic stem cell transplantation has promising outcomes for SCD, Fanconi anemia, and thalassemia, and it may overcome the limitation of the source of allogenic bone marrow transplantation.

How to Facilitate Decision-Making for Hematopoietic Stem Cell Transplantation in Patients With Hemoglobinopathies. The Perspectives of Healthcare Professionals

Hematopoietic stem cell transplantation decision-making for hemoglobinopathy patients is a complex process, and it remains difficult for health care professionals to decide whether and when a hematopoietic stem cell transplantation should be offered. Gaining insight into health care professionals' considerations is required to understand and optimize this decision-making process. A qualitative interview study using semi-structured interviews with eighteen health care professionals. Data were thematically analyzed. Two main themes emerged from the data: (1) Experiencing the influence of a frame of reference and (2) Feeling responsible for a guided decision-making. The frame of reference, meaning the health care professionals' knowledge and experiences regarding hematopoietic stem cell transplantation, influenced the guided decision-making process. Subsequently, three subthemes evolved from the second theme: (a) weighing up disease severity against possible complications, (b) making an effort to inform, and (c) supporting the best fitting decision for the individual patient. The health care professionals' frame of reference determined the hematopoietic stem cell transplantation decision-making process. This demands reflection on the health care professionals' own frame of reference and its influence on decision-making. Furthermore, reflection on the frame of reference is needed by exchange of knowledge and experiences between referring and referred-to healthcare professionals in an open and two-way direction. The transplantation teams have a responsibility of keeping the frame of reference of their referring colleagues up to date and referring health care professionals should share their feelings regarding hematopoietic stem cell transplantation. To guide patients, a shared decision-making approach is supportive, in which eliciting the patients' preferences is highly important. Health care professionals can refine the decision-making process by guiding patients in eliciting their preferences and including these in the decision.