Safety of Long-term Intrathecal Methotrexate Therapy in Progressive Forms of Multiple Sclerosis

Progressive forms of multiple sclerosis (MS) are characterized by gradual worsening of disability with a relative lack of acute clinical and radiographic changes. Although poorly understood, the pathophysiology of progressive disease may be primarily restricted to the central nervous system with less contribution from peripheral immune cells. Few systemic treatment options have been shown to successfully treat progressive MS and even fewer drugs have been examined in the most severely disabled patients (EDSS > 6.0). In 2010, we reported results of intrathecal (IT) administration of methotrexate (MTX) in the treatment of progressive MS for up to 8 treatments. However, the long-term safety of this regiment has not been reported. This study is a retrospective chart analysis of patients who have had 18 IT MTX or more treatments (3- 6 years) at our center in order to further examine the long-term safety and tolerability of IT MTX in this select cohort of advanced MS patients.