Peginterferon beta-1a reduces the evolution of MRI lesions to black holes in patients with RRMS: a post hoc analysis from the ADVANCE study.

The presence of chronic black holes, i.e., chronic lesions that are hypointense on T1-weighted images and are indicative of more severe tissue injury, has been increasingly utilized as a surrogate marker of therapeutic outcome in multiple sclerosis. The ADVANCE study was a 2-year, double-blind, pivotal trial evaluating the safety and efficacy of subcutaneous peginterferon beta-1a 125 mcg in 1512 patients with relapsing-remitting multiple sclerosis (RRMS). This report describes the correlation of clinical outcomes with the evolution of acute lesions into chronic black holes in ADVANCE, and the efficacy of peginterferon beta-1a in reducing this evolution. Treatment with peginterferon beta-1a significantly reduced the mean number of new/enlarging T2-weighted (NET2) lesions (0.76 vs. 1.03 from week 24, p = 0.0037; 0.44 vs. 0.99 from week 48, p < 0.0001) and new gadolinium-enhancing (Gd+) lesions (0.15 vs. 0.32 from week 24, p < 0.0001; 0.09 vs. 0.19 from week 48) that evolved into chronic black holes by 2 years. Patients with NET2 or Gd+ lesions at 24 weeks that evolved into chronic black holes showed significantly worse clinical outcomes, including a greater proportion with 12-week (14.9 vs. 8.4%; p = 0.0167) and 24-week (12.3 vs. 7.0%; p = 0.0333) confirmed disability worsening and higher mean annualized relapse rate (0.62 vs. 0.43; p = 0.0118), compared with patients with lesions that did not evolve into black holes. The correlation was independent of treatment. Reduced risk of evolution of new lesions into chronic black holes with peginterferon beta-1a treatment suggests potential to reduce long-term disability in RRMS by preventing irreversible tissue damage.