Laguna Biotherapeutics received FDA IND clearance for LGNA-100 (QUAIL-100), launching a planned first-in-human phase I study. The trial will enroll pediatric and young adult participants with high-risk acute leukemias and myelodysplastic syndromes after αβ-depleted hematopoietic stem cell transplantation (HSCT) to reduce leukemic relapse. The study design focuses on post-transplant relapse prevention, a setting where immune-mediated strategies can be particularly relevant. The IND clearance is a gatekeeping milestone for dose escalation and initial safety readouts. For pediatric oncology developers, the IND decision signals continued attention on targeted immunotherapies that integrate with advanced HSCT approaches and relapse-risk stratification.