Non-response and disease relapse
When a patient is able to be treated at an institution that offers
tisagenlecleucel, another challenge lies in the failure for them to
either achieve remission or to maintain a sustained remission. Although
tisagenlecleucel has the potential to be definitive therapy for patients
with r/r B-ALL who achieve long-term CAR T cell persistence,
approximately 10-20% of patients fail to enter remission after
receiving anti-CD19 CAR T cell therapy, and 30-50% of patients who
achieve remission will have either antigen-positive or -negative disease
relapse, the majority within 1 year of infusion21,51,54. Specifically, in the ELIANA trial, 38% of
patients who initially achieved a CR after CAR T cell infusion when on
to relapse within 24 months 22 21.
Of those 19 patients who relapsed in that timeframe, 14 (74%) showed
evidence of CD19 escape. Other institutions across the country have also
reported similar antigen negative relapse rates with other CD19 CAR T
cell constructs 47,51,55,56.