Kutny MA, Alonzo TA, Abla O, et al. - All-trans retinoic acid (ATRA) and arsenic trioxide afford a safe treatment option for pediatric acute promyelocytic leukemia (APL) while either eliminating or substantially decreasing the use of cytotoxic chemotherapy in those with standard-risk or high-risk APL, respectively. Relative to the historical comparator group, noninferior 2-year event-free survival (EFS) estimates were obtained, and the regimen conferred benefits such as shorter treatment duration, lower exposure to anthracycline and intrathecal chemotherapy, and fewer days hospitalized.

• This is a nonrandomized, noninferiority trial of 154 pediatric patients with APL who received ATRA and arsenic trioxide therapy.

• A 2-year EFS rate of 98.0% and an overall survival rate of 99.0% were achieved in cases with standard-risk APL; adverse events comprised 1 early death during induction therapy and 1 relapse.

• In those with high-risk APL, the 2-year EFS rate was 96.4% and overall survival rate was 100%; adverse events included 2 relapses and 0 deaths.

• These outcomes met predefined noninferiority criteria (noninferiority margin of 10% among those with standard-risk APL and 14.5% among those with high-risk APL).

• Overall, positive outcomes were evident in standard-risk APL, as well as in those with high-risk APL when they received a novel ATRA and arsenic trioxide–based regimen that included 4 doses of idarubicin during induction therapy only and no maintenance therapy.