The incidences of CRS and neurotoxicity were 42% and 7%, respectively; no patient experienced grade 3-4 CRS or grade 3-4 neurotoxicity. Conclusions IM19 treatment of patients with relapsed or refractory aggressive non-Hodgkin's lymphoma can achieve a high rate of durable responses, with an extremely low incidence of grade 3 or more severe CRS and neurotoxicity.
However, the median progression-free survival (mPFS) of 4-1BB-based product Kymriah was shorter than that of CD28-based Yescarta (2.9 monthsvs. 5.9 months), suggesting that Kymriah was limited in the long-term efficacy. Only one patient (4.5%) experienced grade 3 CRS and grade 3 neurotoxicity. These results demonstrated the safety and durable efficacy of a 4-1BB-based CD19 CAR-T, IM19, which is promising for further development and clinical investigation.