Indirect comparison of tisagenlecleucel and blinatumomab in pediatric relapsed/refractory acute lymphoblastic leukemia

In the absence of head-to-head trials, an indirect-treatment comparison can estimate the treatment effect of tisagenlecleucel in comparison with blinatumomab on rates of complete remission (CR) and overall survival (OS) in patients with relapsed or primary refractory (R/R) acute lymphoblastic leukemia (ALL). Patient-level data from two pivotal trials, ELIANA (tisagenlecleucel; n = 79) and MT103-205 (blinatumomab; n = 70), were used in comparisons of CR and OS, controlling for cross-trial difference in available patient characteristics. Five different adjustment approaches were implemented: stabilized inverse probability of treatment weight (sIPTW); trimmed sIPTW; stratification by propensity score quintiles; adjustment for prognostic factors; and adjustment for both prognostic factors and propensity score. Comparative analyses indicate that treatment with tisagenlecleucel was associated with a statistically significant higher likelihood of achieving CR and lower hazard of death than treatment with blinatumomab. The tisagenlecleucel group exhibited a higher likelihood of CR than the blinatumomab group in every analysis regardless of adjustment approach (odds ratios: 6.71-9.76). Tisagenlecleucel was also associated with a lower hazard of death than blinatumomab in every analysis, ranging from 68% to 74% lower hazard of death than with blinatumomab, determined using multiple adjustment approaches (hazard ratios: 0.26-0.32). These findings support the growing body of clinical trials and real-world evidence demonstrating that tisagenlecleucel is an important treatment option for children and young adults with R/R ALL.