The NHLBI launched the Cure Sickle Cell Initiative in 2018 to support the development of gene-based cures for sickle cell disease (SCD) that will work for all patients, including those ineligible for bone marrow transplants. Researchers involved in the Cure Sickle Cell Initiative helped develop an accurate, affordable, and easy-to-use device for point-of-care diagnosis of SCD in low-resource areas. Read our feature on how this test may transform SCD screening and safe lives around the world.
In early 2020, the NHLBI also became an integral part of a collaboration between NIH and the Bill & Melinda Gates Foundation to develop affordable, safe, and effective gene-based cures for SCD in sub-Saharan Africa. The Cure Sickle Cell Initiative also includes an analysis to ensure that new therapies will be beneficial to patients in ways that matter to them, including affordability and accessibility.
Also in 2020, NHLBI-supported researchers discovered that SCD causes abnormal twists and turns in the blood vessels that supply bone marrow, where red blood cells are made. These disorganized blood vessels deprive the bone marrow of oxygen and could complicate efforts to restore normal red blood cells to patients, such as through bone marrow transplantation or gene therapy. However, in studies on mice, these researchers found that six weeks of blood transfusion restored normal blood vessel architecture in the bone marrow, suggesting a similar protocol could be used as part of cell- and gene-based therapies in patients.
In late 2020, NHLBI-funded researchers reported promising results in a pilot trial of gene therapy to restore the body’s hemoglobin, the red blood cell protein altered in people with SCD. At birth, the body normally switches from making fetal hemoglobin (HbF) to making only adult hemoglobin (HbA). The trial is testing a gene therapy to turn off the switch—a molecule called BCL11A—turning on HbF to replace HbA. Over a median of 18 months, six participants with severe SCD who received this therapy had robust HbF induction, fewer crises and other disease-related events, and less need for transfusions.
Healthcare barriers continue to be an issue for people with SCD. The NHLBI’s Sickle Cell Disease Implementation Consortiumexternal link surveyed 440 adolescents and adults with SCD and found that most were pleased with their primary care but had negative experiences with emergency care during a sickle cell crisis. To address this challenge, one study is embedding each patient’s individualized pain treatment plan in their electronic health records so that it can be accessed quickly by emergency care providers. In another study, researchers are collaborating with patients to develop and test a smartphone app that helps patients who are prescribed hydroxyurea remember to take it regularly. Hydroxyurea can help reduce the frequency of sickle cell crises.