Vaccination with epidermal growth factor (EGF) for non small cell lung cancer (NSCLC) therapy: Preliminary results from a randomized phase II clinical trial

Abstract

2514 Background: Epidermal growth factor (EGF) plays an important role in the regulation of tumor growth. Our approach consists of active immunization with human recombinant EGF coupled to a carrier protein and adjuvanted in Montanide to induce EGF deprivation. Here we report the preliminary results of a randomized Phase II trial designed to test the efficacy of the EGF cancer vaccine in stage IIIb/IV NSCLC patients. Methods: Two groups of 40 unresectable NSCLC patients were compared. All patients received first line chemotherapy and then were randomized to receive the EGF cancer vaccine (group 1) or best supportive care (group 2). Patients were vaccinated on days 0, 7, 14, 21, 51 and then monthly. Anti-EGF antibody titers and EGF concentration ([EGF]) in sera were measured. Results: Fifty patients have been included in the trial (25 vaccinated and 25 controls). Seventy (70) % of the vaccinated patients have shown seroconversion, defined as at least 2X the original antibody titer while 40 % of controls have shown a 2X increase of the natural anti-EGF antibody titers in the follow-up time. However, 50% of the vaccinated subjects developed a good antibody response (GAR), defined at least 4 times above baseline and 1:4000 titer while none of the controls did. The geometric mean of maximal antibody titers was 1: 3500 for group 1 and 1:462 for Group 2. Mean minimal [EGF] was 20 pg/ml for group 1 and 60 pg/ml for group 2. A significant increase in survival was obtained for GAR patients as compared with poor responders. A trend to increase in survival was observed for group 1 (median 8.47 months) as compared with group 2 (median 5.47 months). Conclusions: Preliminary results from a randomized Phase II trial corroborate the immunogenicity and safety of EGF cancer vaccine and the relationship between anti-EGF response and survival of advanced NSCLC patients. No significant financial relationships to disclose.