Impact of blinatumomab on patient outcomes in relapsed/refractory acute lymphoblastic leukemia: evidence to date

Abstract: Relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) is associated with a poor prognosis in both children and adults. Traditionally, there were limited options for salvage therapy, which consisted mostly of conventional chemotherapy. However, in the past 5 years, novel agents have changed our treatment strategies in this population. Blinatumomab, a bispecific CD19 directed CD3 T-cell engager, has shown to be effective in both minimal residual disease and R/R B-cell ALL. In R/R B-cell ALL, blinatumomab was associated with an improved median overall survival of 7.7 months vs 4.0 months with traditional chemotherapy (HR for death, 0.71; 95% CI, 0.55–0.93; P =0.01). It has distinctive side effects as compared to chemotherapy, specifically cytokine release syndrome and neurological toxicities. When compared to standard of care chemotherapy, patients have higher quality of life scores and less financial burden. Using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire, blinatumomab-treated patients fared better and had a longer time to deterioration or death (global health status/quality of life subscale: HR 0.66; 95% CI 0.48–0.92; P =0.009) compared to conventional chemotherapy. Using an incremental cost effective ratio threshold of US$150,000 per quality adjusted life year, blinatumomab was determined to be more cost effective compared to chemotherapy with a probability of 73.7%. This review summarizes the current and future data with blinatumomab in R/R B-cell ALL in the adult and pediatric population. Keywords: acute lymphoblastic leukemia, B-cell acute lymphoblastic leukemia, relapsed/refractory acute lymphoblastic leukemia, blinatumomab, Blincyto