Background: Extending a previous Phase I study, we report the results of a second Phase I autologous tumor cell vaccination trial for patients with recurrent glioblastomas (IND 14379-101, NCT01550523).

Methods: Following surgery, subjects were treated by 24 hour implantation in the rectus sheath of ten biodiffusion chambers containing irradiated autologous tumor cells and IGF-1R AS ODN with the objective of stimulating tumor immunity. Patients were monitored for safety, clinical and radiographic as well as immune responses.

Results: There were no Grade 3 toxicities related to protocol treatment and overall median survival from initial diagnosis was 91.4 weeks. Two protocol survival cohorts with median survivals of 48.2 and 10 weeks were identified and predicted by our pre-treatment assessments of immune function, corroborated by post-vaccination pro-inflammatory cytokine profiles. Longer survival subjects had imaging findings including transient elevations in cerebral blood volume (rCBV) and sustained elevations of apparent diffusion coefficient (ADC) interpreted as transient hyperemia and cell loss.

Conclusions: The vaccine paradigm was well-tolerated with a favorable median survival. Our data support this as a novel treatment paradigm that promotes anti-tumor immunity.