Effect of open label pulse cyclophosphamide therapy on MRI measures of disease activity in five patients with refractory relapsing-remitting multiple sclerosis

Objective. To evaluate the response to cyclophosphamide (CTX) of five patients who failed an average three treatments with multiple other therapeutic agents, using serial monthly MRI measures. Methods. Five patients with relapsing-remitting multiple sclerosis (MS) and documented MRI disease activity were started on monthly pulse intravenous CTX at a dose of 1 g/m². CTX was administered without an induction phase according to the protocol similar to the treatment of lupus nephritis. The five patients were followed with monthly MRI and clinical evaluation for a mean of 28 months. Results. All the patients showed a rapid reduction in the contrast-enhancing lesion frequency and in three patients there was a decrease in the T2 lesion load within the first 5 months after starting CTX treatment. The administration of CTX during overnight hospitalization was safe and well tolerated. Conclusions. These findings suggest that aggressive immunosuppressive therapy may be useful in some rapidly deteriorating refractory patients and further controlled study should be considered in order to full evaluate this type of treatment as a potential therapy in MS.