Concomitant treatment with recombinant Interferon beta 1a (rIFNb-1a) may prolong the beneficial effect of Steroids on Blood-Brain Barrier (BBB) disruption in Relapsing/Remitting Multiple Sclerosis.
In this study, researchers assessed MR images from 19 patients who were treated only with Intravenous MethylPrednisolone (IVMP; 1 g/day for 6 days) for a clinical relapse, as well as images from 10 patients who had a clinical relapse and were treated with IVMP (1g/day for 6 days) while receiving rIFNb-1a.
The authors evaluated the number and volume of enhancing lesions on 4 consecutive, monthly MR images (including one scan prior to and 3 scans following treatment with IVMP).
In the first scan performed after treatment with IVMP, all patients demonstrated a significant reduction in the mean number and volume of enhancing lesions.
However, while patients receiving rIFNb-1a had persistently low enhancement in the subsequent scans, those not receiving rIFNb-1a showed a "rebound effect," or an increase in the number and volume of enhancing lesions.
"The prolonged effect on the BBB as a result of the association between [rIFNb-1a] and Steroids, as shown in this study, may be relevant in the design of clinical trials in which enhancing lesions on monthly MR images are used as outcome measures," the investigators noted.
"Until now it has been thought that the transient effect of Steroids could be avoided by excluding from the statistical analysis the first scan after treatment. However, in future studies the longer effect due to the combined therapy should be considered in the evaluation of treatment efficacy."