Inclusion Criteria:

• Written informed consent signed.
• Male or female patient with histologically proven stage IIIB or IIIC cutaneous melanoma presenting with macroscopic lymph node involvement suitable for surgery.
• The patient must have been surgically rendered free of disease before the randomization.
• Patient is ≥ 18 years old at the time of signing the informed consent form.
• The patient's lymph node tumor shows expression of the MAGE-A3 gene.
• The patient has fully recovered from surgery.
• ECOG performance status of 0 or 1 at the time of randomization.
• The patient must have adequate organ functions as assessed by standard laboratory criteria.
• If the patient is female, she must be of non-childbearing potential, or practice adequate contraception.
• In the opinion of the investigator, the patient can and will comply with all the requirements of the protocol.

Exclusion Criteria:

• The patient suffers from a mucosal or ocular melanoma.
• The patient has or has had any history of in-transit metastases
• The patient has been treated or is scheduled to be treated with an adjuvant anticancer therapy after the surgery that qualifies the patient for inclusion in the present trial.
• The patient requires concomitant chronic treatment with systemic corticosteroids or any other immunosuppressive agents.
• Use of any investigational or non-registered product (drug or vaccine) other than the study treatment.
• The patient has a history of autoimmune disease.
• The patient has a family history of congenital or hereditary immunodeficiency.
• The patient is known to be positive for Human Immunodeficiency Virus (HIV) or has another confirmed or suspected immunosuppressive or immunodeficient condition.
• History of allergic disease or reactions likely to be exacerbated by any component of the treatments.
• The patient has psychiatric or addictive disorders that may compromise his/her ability to give informed consent or to comply with the trial procedures.
• The patient has concurrent severe medical problems, unrelated to the malignancy, that would significantly limit full compliance with the study or expose the patient to unacceptable risk.
• The patient has previous or concomitant malignancies at other sites, except effectively treated non-melanoma skin cancers or carcinoma in situ of the cervix or effectively treated malignancy that has been in remission for over 5 years and is highly likely to have been cured.
• The patient has an uncontrolled bleeding disorder.
• For female patients: the patient is pregnant or lactating.