Abstract
Sickle cell disease (SCD) is a genetically and clinically heterogeneous disorder marked by hemolysis and vaso-occlusion, leading to a wide range of acute and chronic complications. While newborn screening enables early identification, the optimal timing for initiating disease-modifying therapies (DMTs) remains a critical and evolving question. This review explores how genetic and clinical risk factors, along with phenotypic variability, influence treatment timing, emphasizing a shift toward earlier and more personalized interventions. Hydroxyurea, the most widely used DMT, demonstrates strong evidence for early initiation in severe genotypes yet is underutilized due to concerns around long-term effects and adherence challenges. Additional therapies, such as L-glutamine, crizanlizumab, and formerly voxelotor, highlight the growing yet complex therapeutic landscape. Curative and transformative options, such as hematopoietic stem cell transplantation and newly approved gene therapies, underscore the need for individualized decision-making based on risk, disease trajectory, and patient goals. Rethinking treatment paradigms to incorporate multiagent approaches, biomarker-driven strategies, and earlier intervention may yield improved outcomes. Ultimately, optimizing the timing of therapy initiation requires moving from reactive to proactive care models that consider risk, clinical severity, and evolving therapeutic options, with the goal of improving quality of life and long-term survival for individuals living with SCD.