Therapeutic vaccination with Epidermal Growth Factor (EGF) in advanced lung cancer: Analysis of pooled data from three clinical trials

Abstract

We have undertaken the analysis of pooled data from three pilot clinical trials of vaccination with Epidermal Growth Factor (EGF) in patients with advanced non small cell lung cancer (NSCLC), addressing particularly the issue of the relationship between immunization and survival. Eighty-three patients with advanced disease were included in three pilot clinical trials and vaccinated with the EGF Vaccine. The trials were designed to evaluate the immunogenicity and safety of the vaccine using different adjuvants, cyclophosphamide pretreatment or not, and different dosage levels of the vaccine. The vaccine elicited specific anti-EGF antibody titers in 83% of subjects, and 49% developed a good anti-EGF antibody response. The adjuvant, the vaccine dose, and cyclophosphamide pretreatment significantly influenced immunogenicity. Patients that seroconverted survived significantly longer than patients who did not. Good antibody responders survived significantly longer than poor responders. Pooled results from these trials confirm that vaccination with EGF is safe and immunogenic in advanced NSCLC patients. The association between good antibody responses and survival consistently appeared in every single trial independently of the specific trial designs. Although these were small pilot nonrandomized clinical trials not intended to confirm therapeutic effect, the survival of the pooled patient population was statistically greater compared with 163 control patients receiving standard treatment.