The integrase strand transfer inhibitor raltegravir, which is used for the treatment of HIV, had no impact on multiple sclerosis disease activity in a 12-week study published in Multiple Sclerosis and Related Disorders.
The open-label trial began with a pretreatment observation period from day 0 to day 84, during which 23 participants attended testing visits at baseline, then at days 28 and 56. Magnetic resonance imaging scans of the brain and blood tests were performed during visits to determine the baseline number of gadolinium-enhancing lesions and the subsequent rate of lesion development.
Three patients were withdrawn before the treatment phase, which began on day 84, at the fourth visit. The remaining 20 participants received treatment with twice-daily oral raltegravir 400 mg and attended 3 more testing visits at day 112, day 140, and day 168 (the end of the trial period).
Raltegravir had no significant impact on any markers of multiple sclerosis disease activity. Study investigators theorize that this could be due to the short, 12-week study duration or because impact would only be possible with a combination of antiretroviral agents, like those standardly used for HIV infection treatment.
“In conclusion, the INSPIRE trial was the first clinical study on using an HIV antiretroviral therapy to treat [relapsing remitting multiple sclerosis]. While the results did not demonstrate a statistically significant improvement in either the primary or secondary outcomes, it did provide another step in the search for an aetiology of multiple sclerosis.”
Gold J, Marta M, Meier UC, et al. A phase II baseline versus treatment study to determine the efficacy of raltegravir (Isentress) in preventing progression of relapsing remitting multiple sclerosis as determined by gadolinium-enhanced MRI: The INSPIRE study. Mult Scler Relat Disord. 2018; 24:123-128.