The a bispecific, CD19-directed, CD3 T-cell engager immunotherapy.
Blinatumomab is now approved as monotherapy for children aged 1 year or older who have relapsed/refractory, Philadelphia chromosome–negative, CD19-positive B-cell precursor acute lymphoblastic leukemia (ALL). The patients must have received at least two prior therapies, or they must have relapsed after allogeneic hematopoietic stem cell transplant.
The European Commission’s (EC) new approval of blinatumomab extends to all countries in the European Union, as well as Norway, Iceland, and Liechtenstein.
In 2015, the EC approved blinatumomab to treat adults with Philadelphia chromosome–negative, relapsed/refractory B-cell precursor ALL.The EC’s approval of blinatumomab in pediatric patients is based on results from a phase 1/2 study published in the Journal of Clinical Oncology in 2016. The study included 93 pediatric patients with relapsed/refractory B-cell precursor ALL. Patients received blinatumomab as a continuous intravenous infusion – 49 patients in the phase 1 portion of the trial and 44 in phase 2. The patients were followed for 2 years.
There were four dose-limiting toxicities during the phase 1 portion of the trial, two of which were fatal. Three patients had grade 4 cytokine release syndrome (CRS), one had grade 5 cardiac failure (as well as grade 4 CRS), and one had grade 5 respiratory failure. Based on the dose-limiting toxicities, the maximum tolerated dose of blinatumomab was 15 mcg/m2 per day, but a stepwise dosage was recommended to reduce the risk of CRS.
The recommended dose was 5 mcg/m2 per day on days 1-7 and 15 mcg/m2 per day on days 8-28 for cycle 1, and 15 mcg/m2 per day on days 1-28 for subsequent cycles, according to the study results.Among the 70 patients who received the recommended dose of blinatumomab, 27 (39%) achieved a complete response within the first two cycles. A total of 14 of these patients (52%) achieved minimal residual disease negativity.