A Phase I Study of a Therapeutic Vaccine Candidate in Patients With Localized Breast Cancer at High-Risk of Relapse

This study is a three dose level open-label, non-randomized, dose-escalation study Phase I of the safety of the vaccine candidate MAG-Tn3 + AS15 administered to patients with HER2 negative, high-risk localized breast cancer in remission. A maximum of 30 patients will be included in the study: * 3 or 6 patients in the 1st dose level (30 µg) * 6 or 12 patients in the 2nd dose level (100 µg) * 6 or 12 patients in the 3rd dose level (300 µg) The clinical study phase I is composed of a vaccination period of about 4 months (16 weeks) and a follow-up period of 36 months (3 years). Each patient will receive one of the three escalating doses of MAG-Tn3 in combination with a fixed dose of AS15 adjuvant. The subject will receive 6 vaccine injections, administered by intramuscular injection with a 3-weeks interval between injections. Each patient will be followed 36 months after the last injection. The follow-up period is composed of a short-term follow-up period of 6 months and a long-term follow-up period of 30 months. A total of 20 visits will be required for each patient. Clinical data and blood samples will be collected for analysis for each patient. Clinical study data will be recorded for each patient on source documentation and then entered on electronic CRFs (eCRFs) using a proprietary Electronic Data Capture (EDC) Clinical Data Base Software System. The eCRF data are to be entered by site personnel trained in EDC data entry. A monitor will visit the site regularly to check the completeness of patient records, the accuracy of entries on the e-CRFs, the adherence to the protocol and to Good Clinical Practice, the progress of enrollment, and to ensure that study drug is being stored, dispensed, and accounted for according to specifications. Institut Pasteur or designated CRO will conduct data management. Data entered into EDC will be housed in a central database. Changes will be tracked to provide an audit trail. Interactive data checks will be carried out as applicable during the data entry process. Additional data checks are programmed to identify errors in the SAS datasets. Applicable queries based on the SAS datasets will be added to EDC for resolution by data management personnel. At the conclusion of the study, when all data have been entered and source document verified, with no outstanding queries remaining, the Investigator of each site will be required to electronically sign each patient's casebook to confirm that the data for each patient are complete and accurate and consistent with the patient's source documents. The data will then be locked to prevent further editing. Concomitant medications entered into the database will be coded using the WHO Drug Reference List, which employs the Anatomical Therapeutic Chemical classification system. Medical history/current medical conditions and adverse events terminology will be coded using the Medical dictionary for regulatory activities.The newest version of the dictionary at data base lock will be used.