B cell progenitor acute lymphoblastic leukemia (BCP-ALL) is the most common childhood malignancy. It is initiated by multiple genetic alterations, causing a maturation arrest and accumulation of abnormal progenitor B cells. Current treatment protocols with chemotherapy have led to favorable outcomes, but are associated with significant toxicity and risk of side effects, highlighting the necessity for highly effective, less toxic, targeted drugs that also show efficacy in children experiencing relapse.