The immunotherapeutic agent, Blincyto (blinatumomab), improves survival compared to standard therapy among patients with B-cell precursor, Philadelphia chromosome-negative (Ph-) acute lymphoblastic leukemia (BCP-ALL) that has stopped responding to prior therapies. These results were presented at a presidential symposium at the 2016 annual European Hematologic Association (EHA) meeting.
Acute lymphoblastic leukemia (ALL) is the most aggressive type of adult leukemia. Treatment for Ph-, precursor ALL remains limited, particularly among patients whose disease has progressed following prior therapies, with low rates of long-term survival.
Blinatumomab is an agent that stimulates immune cells, called T cells, to kill B cells – the type of cell from which B-cell ALL originates. Blinatumomab is approved by the United States Food and Drug Administration (FDA) for treatment of this disease. However, the approval was based on “accelerated approval” by the FDA; therefore, longer follow-up data is necessary to determine long-term outcomes.
Results presented at the 2016 EHA meeting were updated from the TOWER trial, which included 405 patients with B-cell precursor, Ph-, ALL. All patients had progression of their cancer despite prior therapies. In the trial, one group of patients was treated with blinatumomab and the other group was treated with standard chemotherapy regimens.
- Median overall survival was 7.8 months for patients treated with blinatumomab, compared with only 4 months for those treated with standard therapies.
- Anti-cancer responses were significantly higher among the group of patients treated with blinatumomab compared to those treated with standard therapies.
- Upon subgroup analyses, blinatumomab remained effective regardless of the amount of prior therapy or age of the patient.
- Safety was comparable between the two treatment groups.
These results provide further evidence that blinatumomab improves survival among patients with B-cell precursor, Ph-, ALL that has stopped responding to prior therapies. Based on these data, the Data Monitoring Committee (DMC) has recommended stopping the TOWER trial prior to its planned final analysis.
Reference: Topo M, Stein A, Gokbuget N, et al. Blinatumomab improved overall survival in patients with relapsed or refractory Philadelphia negative B-cell precursor acute lymphoblastic leukemia in a randomized, open-label phase 3 study (TOWER). Proceedings from the 2016 annual EHA meeting. Abstract S149. Available at: http://learningcenter.ehaweb.org/eha/2016/21st/135182/max.topp.blinatumomab.improved.overall.survival.in.patients.with.relapsed.or.html?f=p16m3l11456. Accessed June 17, 2016.