Gilead Sciences Inc. said its KTE-C19 gene therapy for a type of leukemia had a 71% response rate in an ongoing phase 1/2 trial.
The ongoing Zuma-3 trial, conducted by Gilead unit Kite Pharma Inc., is evaluating the safety and efficacy of KTE-C19 in acute lymphoblastic leukemia patients whose disease is refractory to or has relapsed following standard chemotherapy or hematopoietic stem cell transplantation. At the time of data cutoff, 24 patients were evaluable for a response.
Seventeen of the 24 patients being treated with the chimeric antigen receptor T-cell therapy saw complete tumor remission, with a minimum of eight weeks of follow-up, according to results presented at the American Society of Hematology conference in Atlanta.
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None of the patients had any detectable minimal residual disease at the time of data cutoff, including in those with high tumor burden and high-risk genetic abnormalities.
The safety results were consistent with the known toxicities of KTE-C19. One patient died due to a cerebrovascular accident unrelated to KTE-C19 while a second patient experienced fatal cytokine release syndrome, a toxic reaction to the reinfused cells that can sometimes be deadly.
Acute lymphoblastic leukemia is an aggressive type of blood cancer which can also involve the lymph nodes, spleen, liver, central nervous system and other organs.

