Sickle cell disease (SCD) is a hereditary blood disorder caused by a specific mutation in the β-globin gene, leading to the production of hemoglobin S, which deforms red blood cells, causing occlusion in small blood vessels. This results in pain, anemia, organ damage, infections, and increased stroke risk. Treatment options, including disease-modifying therapies and curative hematopoietic stem cell transplants, have limited accessibility. Recently, autologous gene therapy has emerged as a promising curative option, particularly for SCD. Gene editing techniques such as CRISPR, base editing, and prime editing offer potential to correct this mutation. In this review, we discuss recent preclinical studies and clinical trials of gene and cell therapies, focusing on the progress of FDA-approved treatments like Lyfgenia and Casgevy. We also examine the many challenges, including accessibility, safety, and long-term efficacy, which continue to shape the future of SCD gene therapy.
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