The FDA has granted approval to blinatumomab (Blincyto) for the treatment of adult and pediatric patients, one month and older, with CD19-positive, Philadelphia chromosome-negative B-cell precursor acute lymphoblastic leukemia (B-ALL) in the consolidation phase, irrespective of measurable residual disease (MRD) status. This decision aims to improve overall survival rates in patients undergoing treatment for this aggressive form of leukemia. The approval marks the third indication for BLINCYTO.
The approval is based on data from two pivotal Phase 3 clinical trials, ECOG-ACRIN E1910 and Study 20120215, which demonstrated significant improvements in overall survival (OS) and relapse-free survival with the addition of blinatumomab to standard chemotherapy regimens.
Superior Overall Survival in E1910 Study
The ECOG-ACRIN E1910 study (NCT02003222) was a randomized, controlled trial involving adult patients with newly diagnosed Philadelphia chromosome-negative B-ALL. Patients in hematologic complete remission (CR) or CR with incomplete peripheral blood count recovery after induction and intensification chemotherapy were randomized 1:1 to receive either:
- Blinatumomab plus multiple cycles of intensive chemotherapy (n = 112)
- Intensive chemotherapy alone (n = 112)
The 3-year OS rate in the blinatumomab arm was 84.8% (95% CI, 76.3%-90.4%) compared to 69% (95% CI, 58.7%-77.2%) in the chemotherapy arm. At a median follow-up of 4.5 years, the 5-year OS rates were 82.4% (95% CI, 73.7%-88.4%) and 62.5% (95% CI, 52.0%-71.3%), respectively. The hazard ratio for OS was 0.44 (95% CI, 0.23-0.76; P = .003).
Dr. Selina M. Luger, professor of hematology-oncology at the University of Pennsylvania, stated, "In the E1910 study, blinatumomab reduced risk of death and showed a remarkable improvement in overall survival. This approval redefines the standard of care for patients with B-ALL and provides them with a more effective treatment option than standard chemotherapy alone."
Improved Outcomes in Pediatric and Young Adult Patients
Study 20120215 (NCT02393859) was a randomized, open-label, multicenter trial that enrolled pediatric and young adult patients with Philadelphia chromosome-negative B-ALL. Patients were randomized 1:1 to receive blinatumomab (n = 54) or intensive chemotherapy (IntReALLHR2010 HC3; n = 57) as the third consolidation cycle.
The 5-year OS rate in the blinatumomab arm was 78.4% (95% CI, 64.2%-87.4%) compared to 41.4% (95% CI, 26.3%-55.9%) in the chemotherapy arm (HR, 0.35; 95% CI, 0.17-0.70). The 5-year relapse-free survival rate was 61.1% (95% CI, 46.3%-72.9%) in the blinatumomab arm and 27.6% (95% CI, 16.2%-40.3%) in the chemotherapy arm (HR, 0.38; 95% CI, 0.22-0.66).
Safety and Adverse Events
In the E1910 study, common adverse events in the blinatumomab arm included neutropenia, thrombocytopenia, anemia, leukopenia, headache, infection, nausea, lymphopenia, diarrhea, musculoskeletal pain, and tremor. In Study 20120215, the most common adverse reactions in the blinatumomab arm were pyrexia, nausea, headache, rash, hypogammaglobulinemia, and anemia.
Blinatumomab: A BiTE® Immuno-Oncology Therapy
Blinatumomab (Blincyto) is the first globally approved Bispecific T-cell Engager (BiTE®) immuno-oncology therapy. It targets the CD19 surface antigen on B cells, engaging T cells to recognize and eliminate malignant cells. This mechanism helps the body's immune system detect and target cancer cells, triggering cancer cell death (apoptosis).
Regulatory Context
The FDA's review was conducted under Project Orbis, involving collaboration with regulatory agencies in Brazil, Canada, Switzerland, and the United Kingdom. The application also utilized the Real-Time Oncology Review pilot program and Assessment Aid to streamline the review process. Blinatumomab was granted priority review, breakthrough therapy designation, and orphan drug designation, expediting its approval for this critical indication.
