A deletion variant of epidermal growth factor receptor (EGFRvIII) is a known driver mutation in a subset of primary and secondary glioblastoma multiforme. Adoptive transfer of genetically modified chimeric antigen receptor (CAR) lymphocytes has demonstrated efficacy in hematologic malignancies but is still early in development for solid cancers. The surface expression of the truncated extracellular ligand domain created by EGFRvIII makes it an attractive target for a CAR-based cancer treatment. Patients with recurrent glioblastoma expressing EGFRvIII were enrolled in a dose escalation phase I trial, using a third-generation CAR construct derived from a human antibody. Transduced cells were administered after lymphodepleting chemotherapy and supported posttransfer with intravenous interleukin-2. The dose escalation proceeded at half-log increments from 107 to >1010 cells. Primary endpoints were safety and progression-free survival. Eighteen patients were treated with final infusion products ranging from 6.3×106 to 2.6×1010 anti-EGFRvIII CAR+ T cells. Median progression-free survival was 1.3 months (interquartile range: 1.1–1.9), with a single outlier of 12.5 months. Two patients experienced severe hypoxia, including one treatment-related mortality after cell administration at the highest dose level. All patients developed expected transient hematologic toxicities from preparative chemotherapy. Median overall survival was 6.9 months (interquartile range: 2.8–10). Two patients survived over 1 year, and a third patient was alive at 59 months. Persistence of CAR+ cells correlated with cell dose, but there were no objective responses. Administration of anti-EGFRvIII CAR-transduced T cells did not demonstrate clinically meaningful effect in patients with glioblastoma multiforme in this phase I pilot trial.
§Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD
†Editas Medicine, Cambridge, MA
‡Stanford Center for Cancer Cell Therapy, Stanford Cancer Institute, Palo Alto, CA
∥Sandra and Edward Meyer Cancer Center, Weill Cornell Medical College, New York, NY
Reprints: Stephanie L. Goff, Surgery Branch, National Cancer Institute, NIH, 10 Center Drive, Room 3-3940, Bethesda, MD 20892-1201 (e-mail: firstname.lastname@example.org).
Received December 12, 2018
Accepted January 29, 2019