Current and emerging maintenance strategies after stem cell transplantation in children and adolescents with acute leukemias

Hematopoietic stem cell transplantation (HSCT) can promote durable long-term remissions for children and adolescents with high-risk acute leukemias. While many patients with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) can achieve a cure, post-HSCT relapse remains a possibility for many. Recent therapeutic advances, particularly in the realm of targeted therapeutics, have revolutionized both first-line and relapsed/refractory management strategies, opening the door to more personalized and potentially less toxic approaches to treatment. Many of these agents have also either been proposed or have been actively investigated as having a role in the post-HSCT setting. Post-HSCT relapse often carries a dismal prognosis, and early prophylactic intervention has in many cases been shown to improve outcomes. Herein, we comprehensively review maintenance strategies for prevention of post-HSCT relapse of ALL and AML, with a specific focus on pediatric and adolescent populations. While drawing on experience in adult patients, we highlight data specific to pediatrics where available and draw attention to areas where further research in children and adolescents is needed. Future efforts aimed at determining who will benefit from, when to initiate and discontinue, and what agent(s) to employ as maintenance will be crucial to optimizing post-HSCT outcomes.