Clinical representativeness of pivotal trials for T-cell engagers in relapsed/refractory follicular lymphoma

To characterize trial populations of T-cell–engaging therapies, including bispecific antibodies and chimeric antigen receptor T-cell therapies, for relapsed/refractory (R/R) follicular lymphoma (FL) after ≥ 2 systemic therapies and the extent to which they represent real-world R/R FL populations. Inclusion/exclusion criteria and baseline characteristics were compared descriptively for EPCORE NHL-1 (epcoritamab, N = 128), GO29781 (mosunetuzumab, N = 90), ELARA (tisagenlecleucel [tisa-cel], N = 97), and ZUMA-5 (axicabtagene ciloleucel [axi-cel], N = 124). Real-world data from the COTA Healthcare (New York, NY) and Optum Market Clarity (Eden Prairie, MN) databases contextualized the clinical representativeness of trial populations. The epcoritamab trial enrolled a higher proportion of patients who were older, had higher Follicular Lymphoma International Prognostic Index scores, and were more double-refractory versus other trials. Notably, 37% of epcoritamab trial patients would have been excluded from the mosunetuzumab trial, 30% from the tisa-cel trial, and 29% from the axi-cel trial. These excluded subgroups were characterized by factors associated with poor clinical outcomes. The epcoritamab trial enrolled more broadly and was more representative of typical R/R FL patients than the mosunetuzumab, tisa-cel, and axi-cel trials. Differences in patient characteristics should be considered when evaluating the comparative benefits of T-cell engagers in R/R FL after ≥ 2 systemic therapies. A number of therapies have been approved recently for the treatment of relapsed/refractory follicular lymphoma, a type of blood cancer. Epcoritamab, mosunetuzumab, tisagenlecleucel (tisa-cel), and axicabtagene ciloleucel (axi-cel) have demonstrated efficacy in separate key clinical trials. However, it is difficult to know which therapy works better since they have not been compared against each other in the same study. To better understand how the efficacy of these treatments compare, we looked at the types of patients who were included in the clinical trials for epcoritamab, mosunetuzumab, tisa-cel, and axi-cel, asking whether patient populations differed across the different trials. Trials that are more restrictive in their selection of study participants may end up with populations that do not reflect the types of people treated in an everyday practice environment. Therefore, we also looked at real-world patient data to see how similar the patients included in these trials were to patients in real-world clinical practice. Overall, the populations in the 4 trials differed substantially. The epcoritamab trial included a broader, more clinically diverse population compared with the mosunetuzumab, tisa-cel, and axi-cel trials. Notably, 37% of epcoritamab trial patients would have been excluded from the mosunetuzumab trial, 30% from the tisa-cel trial, and 29% from the axi-cel trial. Because of this, the epcoritamab trial (EPCORE NHL-1) may better reflect real-world clinical practice compared with trials of similar therapies, and the results are more generalizable to patients in clinical practice. Differences in the trial populations should be considered when comparing these treatments.