Augmenting Cerebral Blood Flow to Treat Established Multiple Sclerosis

Cerebral perfusion is altered in many disease states, including MS. Altered perfusion has been seen in patients with all multiple sclerosis (MS) phenotypes and is well established as occurring early in relapsing-remitting disease. Previous research in our laboratory has shown that reduced cerebral perfusion in MS patients is a precursor to the formation of chronic lesions. In addition, studies have suggested that "virtual hypoxia", resultant from the combination of diminished cerebral perfusion and increased energy demand, contributes to tissue damage that strongly correlates with clinical disability in persons with MS. Our preliminary studies have already shown short-term increases in global and regional cerebral perfusion in MS patients after therapy with acetazolamide (ACZ). The central hypothesis is that if cerebral perfusion is important in tissue injury, then MS lesions within hypoperfused areas are more likely to develop permanent tissue damage, and medications that improve cerebral perfusion might beneficially alter the evolution of MS plaques, enhance remyelination and repair and diminish clinical disability progression. Sixty MS patients will be enrolled in this single-center exploratory RCT. Half of the patients will be randomly assigned to get ACZ treatment in phase 1 consisting of 24 weeks on ACZ, followed by another 24 weeks on ACZ during phase 2. The other half of the patients will be assigned to placebo for 24 weeks in phase 1 and then switched to ACZ and followed for 24 weeks in phase 2. This study will utilize various imaging techniques to determine the degree to which cerebral blood flow is improved in MS subjects after administration of ACZ.