Successful Phase 1 ZUMA-3 trial of KTE-C19 (axicabtagene ciloleucel) in r/r/acute lymphoblastic leukemia- Kite Pharma

Kite Pharma, Inc., announced that 73 percent of patients achieved complete remission, including those with incomplete or partial recovery of bone marrow, in an updated analysis of the Phase 1 ZUMA-3 trial of KTE-C19 (axicabtagene ciloleucel) in adults with high burden relapsed/refractory acute lymphoblastic leukemia (r/r ALL). All responders tested negative for minimal residual disease (MRD).

The data were presented in a poster session at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, IL . (Abstract #3024)and follow previously reported results from the American Society of Hematology (ASH) Annual Meeting in December 2016. In the Phase 1 trial, 11 patients were treated with KTE-C19 at two target dose levels (2.0�106/kg and 1.0x106/kg). No dose-limiting toxicities (DLT) occurred in the trial. Both doses were tolerable and responses were achieved at each level. Ongoing complete remissions have been observed at 2.0+ to 7.4+ months.Three of 11 (27 percent) patients had grade 3 or higher cytokine release syndrome (CRS) and six of 11 (55 percent) had grade 3 or higher neurologic events. These adverse events were generally reversible. As previously reported at ASH 2016, one patient experienced fatal CRS. In order to further improve the safety profile of KTE-C19, ZUMA-3 is also evaluating additional patients who will receive tocilizumab within 36 hours post-KTE-C19 infusion, and a lower dose of 0.5�106 CAR T cells/kg.

KTE-C19 was successfully manufactured in this multi-center trial for all patients in six days across a range of absolute lymphocyte and blast counts in a centralized and streamlined process. Responses were observed across a wide range of CD4:CD8 ratios and T-cell phenotypes.

Kite plans to initiate Phase II of the ZUMA-3 trial in 2017.