FDA approves Besponsa for certain pediatric patients with advanced leukemia
The FDA approved inotuzumab ozogamicin for use in pediatric patients with relapsed or refractory CD22-positive B-cell precursor acute lymphoblastic leukemia, according to a press release.
The agency granted both priority review and orphan drug designation to the application. The agent also received previous approval for use in adults with relapsed or refractory B-cell precursor ALL.
The FDA based the new indication on results of a single-arm study assessing the efficacy of inotuzumab ozogamicin (Besponsa, Pfizer) — an antibody-drug conjugate — in 53 pediatric patients (all aged 1 year or older) with relapsed or refractory CD22-positive B-cell precursor ALL.
The multicenter trial evaluated two dose levels: an initial dose of 1.4 mg/m2 per cycle in 12 patients and 1.8 mg/m2 per cycle in 41 patients. Premeditations included 1 mg/kg methylprednisolone for a maximum of 50 mg, an antipyretic and an antihistamine.
Study participants received a median of two cycles of therapy.
Complete remission, duration of complete remission and the proportion of pediatric patients with minimal residual disease-negative complete remission served as the open-label study’s main efficacy outcome measurements.
Results showed 22 of the 53 patients (42%) achieved complete remission (95% CI, 28.1-55.9) and a median duration of complete remission of 8.2 months (95% CI, 2.6 to not evaluable).
Additionally, study investigators reported minimal residual disease negativity in 21 of 22 patients who achieved complete remission (95.5%; 95% CI, 77.2-99.9) based on flow cytometry and in 19 of 22 patients (86.4%; 95% CI, 65.1–97.1) based on real-time quantitative polymerase chain reaction.
Adverse reactions occurring in at least 20% of study participants included thrombocytopenia, pyrexia, anemia, vomiting, infection, hemorrhage, neutropenia, nausea, leukopenia, febrile neutropenia, increased transaminases, abdominal pain and headache.