PLASMA-EXCHANGE COMBINED WITH AZATHIOPRINE IN MULTIPLE-SCLEROSIS USING SERIAL GADOLINIUM-ENHANCED MRI TO MONITOR DISEASE-ACTIVITY - A RANDOMIZED SINGLE-MASKED CROSS-OVER PILOT-STUDY

We enrolled 11 patients with secondary progressive MS in a randomized single-masked cross-over study of plasma exchange (PE) in combination with azathioprine 2 mg/kg. PE was performed once a week for 4 weeks an d thereafter every second week for 20 weeks (14 treatments). Eight pat ients completed the whole trial, and three patients discontinued the t rial, two during the run-in period of azathioprine treatment and one a t the introduction of PE. The primary efficacy variables were the numb er of gadolinium-enhancing lesions and the occurrence of new enhancing lesions on-serial MRT performed every 3 weeks during the PE-and the c ontrol period. Secondary efficacy variables were the total MS lesion l oad on T-2-weighted MRI, multimodal evoked potentials, and clinical ne urologic ratings. No significant differences were found regarding the number of enhancing lesions or occurrence of new enhancing lesions in the two periods. Although the total MS lesion load on MRI was signific antly lower (p < 0.02) and central motor conduction times decreased si gnificantly (p < 0.05) during PE, this small study did not provide suf ficient evidence for a significant beneficial effect of PE or encourag e a subsequent large randomized parallel group study.