Study to Compare the Clinical and Radiological Efficacy of 625 mg Versus 1250 mg of Oral Methylprednisolone in Patients With Multiple Sclerosis in Relapse

DESIGN: Phase IV clinical trial, multicentre, randomized and double blind, active drug controlled and parallel groups. Patients will be randomised to a high dose of oMP vs a lower-high dose of oral Methylprednisolone (oMP). SETTING: 9 MS Units from 9 hospitals of the public health system with extensive experience in treating patients with MS and design and participation in clinical trials. PROCEDURES: After signing the informed consent, the inclusion and exclusion criteria specific to the study will be checked. The diagnostic test will take place prior to administration of study medication and will include medical history, neurological examination (EDSS measurement) taking of vital signs (blood pressure, heart rate and body temperature) and MRI. Concomitant medication will be checked. Patients will be instructed about the requirements during the study. The trial medication will be provided to the patient in the medical office (day 1 of the study), where the patient will remain until the intake. This action will be repeated the following 2 days. The latency period from the beginning of the relapse until the start of treatment will be registered. The questionnaires of tolerance will be completed. Day 1 will be defined as the first day on which first dose of oMP is administered. Once given the treatment under study, the adverse events reported spontaneously or after question will be collected. There will be follow-up visits at 7 and 28 days, and 3 months after initiation of treatment. At baseline, prior to drug administration, and on days 7 and 28 after initiation of treatment, a brain MRI with and without contrast will be performed. In case of adverse events or laboratory abnormalities, the patients could have an accessory follow-up visits until resolution. Randomization will be performed on the day of administration (day 1) The treatments are: Group A: Methylprednisolone 1250 mg / day orally for 3 days Group B: Methylprednisolone 625 mg / day orally for 3 days