MAGE-A3 cancer immunotherapeutic in resected stage IB-III NSCLC patients with or without sequential or concurrent chemotherapy

7013 Background: Previous trials with the MAGE-A3 recombinant (rec) protein formulated with an immunostimulant have shown induction of specific immune responses and signals of clinical activity in different cancer diseases. In this phase I/II study (NCT 00455572), we evaluated the safety profile of the MAGE-A3 cancer immunotherapeutic (CI), formulated with the rec MAGE-A3 protein and the AS15 immunostimulant, and the induction of specific immune response with or without adjuvant chemotherapy (CT). Methods: MAGE-A3 CI was administered i.m. 8q3w in resected MAGE-A3+ stage IB-III NSCLC patients (pts). Three cohorts (C) were evaluated: Immunization with concurrent cisplatin plus vinorelbine (C1), sequentially after the same CT (C2) or with no CT (C3). The anti-MAGE-A3 humoral and cellular immune responses were evaluated by ELISA and intracellular cytokine staining (T cells producing both IFNg and TNF) respectively. Adverse Events (AEs) were graded according to CTCAE v. 3.0. Results: A total of 38/55 treated pts received the 8 doses schedule (15/19 in C1, 14/18 in C2, 9/18 in C3). Almost all pts reported at least one AE, mostly general constitutional disorders and administration site reactions. Six patients reported related grade 3 AEs. No related grade 4-5 AE or related SAE were reported. Immunogenicity results in the total treated population are reported in the table below. Conclusions: In this trial, patients in cohorts 2 and 3 correspond to the two populations enrolled in the Phase III MAGRIT trial evaluating the same MAGE-A3 CI. The phase I/II results suggest that this CI is well tolerated and induces in all treated pts specific antibodies against MAGE-A3 after 4 doses in presence or not of concurrent or sequential adjuvant CT. About 25% of the treated pts are considered as CD4 responders in presence or not of concurrent or sequential adjuvant CT. [Table: see text]