Safety and Efficacy Study of Doxycycline in Combination With Interferon-B-1a to Treat Multiple Sclerosis

Inclusion Criteria: age 18-55 Relapsing-Remitting Multiple Sclerosis (RRMS) Avonex therapy for 6 months prior continuous annualized relapse rate >2 during Avonex therapy most recent relapse within 60 days of baseline entry Expanded Disability Status Scale (EDSS) 1.5-4.5 one or more gadolinium (Gd+) MRI lesions on a baseline MRI no history of immune modulator or immunosuppressant therapy used in combination with Avonex (other then GSC administer for clinical relapses) not participating in any other study of ms therapeutics Serum neutralizing antibodies (NABs) titer to Avonex <20 Exclusion Criteria: Medical or Psychiatric conditions that will affect patients ability to provide informed consent inability to undergo MRI clinically serious medical conditions or significantly abnormal labs no use of these medications or procedures within six months prior to study: *monoclonal antibodies,total lymphoid radiation,systemic steroids,cytotoxic or immunosuppressive medications such as mitoxantrone or cyclophosphamide or any other investigational drugs Interferon neutralizing antibody titers >20 no breast feeding or pregnant no patients with any systemic illness,psychiatric condition or other disorder that would concern safety of patient to complete procedures of protocol abnormal blood test clinically significant abnormality on chest x-ray (CXR)