Blood transfusion support for sickle cell patients during haematopoietic stem cell transplantation: a single-institution experience

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.

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.

Sickle Cell Disease in Bahia, Brazil: The Social Production of Health Policies and Institutional Neglect

A disease is considered neglected when it is not given due priority in health policies despite the social relevance of that disease, either in terms of the number of individuals affected by it or its morbidity or mortality. Although the causes are structural, neglect in health does not occur in a vacuum. In this paper, we explore how sickle cell disease (SCD) is constructed and neglected in Brazil, based on insights from our long-term participatory qualitative research in the state of Bahia. We present five overarching themes relevant to the social production of SCD, and associated health policies in Brazil: (1) The achievements and setbacks to overcome neglect in SCD, (2) Continuity of comprehensive SCD care; (3) Social movements of people with SCD; (4) Biocultural citizenship; and (5) Academic advocacy. We conclude that it is insufficient to merely recognize the health inequities that differentiate white and black populations in Brazil; racism must be understood as both a producer and a reproducer of this process of neglect. We conclude with a set of recommendations for the main SCD stakeholder groups committed to improving the lives of people living with SCD.