Greater chemotherapy-induced lymphopenia enhances tumor-specific immune responses that eliminate EGFRvIII-expressing tumor cells in patients with glioblastoma.

Published

Journal Article

Epidermal growth factor receptor variant III (EGFRvIII) is a tumor-specific mutation widely expressed in glioblastoma multiforme (GBM) and other neoplasms, but absent from normal tissues. Immunotherapeutic targeting of EGFRvIII could eliminate neoplastic cells more precisely but may be inhibited by concurrent myelosuppressive chemotherapy like temozolomide (TMZ), which produces a survival benefit in GBM. A phase II, multicenter trial was undertaken to assess the immunogenicity of an experimental EGFRvIII-targeted peptide vaccine in patients with GBM undergoing treatment with serial cycles of standard-dose (STD) (200 mg/m(2) per 5 days) or dose-intensified (DI) TMZ (100 mg/m(2) per 21 days). All patients receiving STD TMZ exhibited at least a transient grade 2 lymphopenia, whereas those receiving DI TMZ exhibited a sustained grade 3 lymphopenia (<500 cells/μL). CD3(+) T-cell (P = .005) and B-cell (P = .004) counts were reduced significantly only in the DI cohort. Patients in the DI cohort had an increase in the proportion of immunosuppressive regulatory T cells (T(Reg); P = .008). EGFRvIII-specific immune responses developed in all patients treated with either regimen, but the DI TMZ regimen produced humoral (P = .037) and delayed-type hypersensitivity responses (P = .036) of greater magnitude. EGFRvIII-expressing tumor cells were also eradicated in nearly all patients (91.6%; CI(95): 64.0%-99.8%; P < .0001). The median progression-free survival (15.2 months; CI(95): 11.0-18.5 months; hazard ratio [HR] = 0.35; P = .024) and overall survival (23.6 months; CI(95): 18.5-33.1 months; HR = 0.23; P = .019) exceeded those of historical controls matched for entry criteria and adjusted for known prognostic factors. EGFRvIII-targeted vaccination induces patient immune responses despite therapeutic TMZ-induced lymphopenia and eliminates EGFRvIII-expressing tumor cells without autoimmunity.

Full Text

Duke Authors

Cited Authors

  • Sampson, JH; Aldape, KD; Archer, GE; Coan, A; Desjardins, A; Friedman, AH; Friedman, HS; Gilbert, MR; Herndon, JE; McLendon, RE; Mitchell, DA; Reardon, DA; Sawaya, R; Schmittling, R; Shi, W; Vredenburgh, JJ; Bigner, DD; Heimberger, AB

Published Date

  • March 2011

Published In

Volume / Issue

  • 13 / 3

Start / End Page

  • 324 - 333

PubMed ID

  • 21149254

Pubmed Central ID

  • 21149254

Electronic International Standard Serial Number (EISSN)

  • 1523-5866

Digital Object Identifier (DOI)

  • 10.1093/neuonc/noq157

Language

  • eng

Conference Location

  • England