Temporal evolution of new T1-weighted hypo-intense lesions and central brain atrophy in patients with a first clinical demyelinating event treated with subcutaneous interferon β-1a

Objective Evaluate the effect of subcutaneous interferon ss-1a (sc IFN ss-1a) versus placebo on the evolution of T1-weighted MRI lesions and central brain atrophy in in patients with a first clinical demyelinating event (FCDE). Methods Post hoc analysis of baseline-to-24 month MRI data from patients with an FCDE who received sc IFN ss-1a 44 mu g once- (qw) or three-times-weekly (tiw), or placebo, in REFLEX. Patients were grouped according to treatment regimen or conversion to clinically definite MS (CDMS) status. The intensity of new lesions on unenhanced T1-weighted images was classified as T1 iso- or hypo- intense (black holes) and percentage ventricular volume change (PVVC) was assessed throughout the study. Results In patients not converting to CDMS, sc IFN ss-1a tiw or qw, versus placebo, reduced the overall number of new lesions ( P < 0.001 and P = 0.005) and new T1 iso-intense lesions (P < 0.001 and P = 0.002) after 24 months; only sc IFN ss-1a tiw was associated with fewer T1 hypo-intense lesions versus placebo ( P < 0.001). PVVC findings in patients treated with sc IFN ss-1a suggested pseudo-atrophy that was similar to fivefold greater versus placebo in the first year of treatment (placebo 1.11%; qw 4.28%; tiw 6.76%; P < 001); similar findings were apparent for non-converting patients. Conclusions In patients with an FCDE, treatment with sc IFN ss-1a tiw for 24 months reduced the number of new lesions evolving into black holes.

Automated summary

A post hoc analysis found that subcutaneous interferon ss-1a (sc IFN ss-1a) treatment can reduce the number of new lesions and the likelihood of these lesions evolving into black holes in patients with a first clinical demyelinating event (FCDE), compared to placebo.