Assessing the HERV-W Env ANtagonist GNbAC1 for Evaluation in an Open Label Long-term Safety Study in Patients With Multiple Sclerosis

Main Inclusion Criteria: * Patients must have completed Period 2 of study GNC-003 and must meet all eligibility criteria for the GNC-004 study * Patients (male or female with reproductive potential) must agree to use highly effective methods of birth control * Provision of written informed consent to participate prior to any trial procedure as shown by signature on the subject consent form. Main Exclusion Criteria: * Patients not having completed the study GNC-003 * Pregnancy * The emergence of any disease diagnosis during the course of study GNC-003 that is not MS and could better explain the patient's neurological signs and symptoms