OBJECTIVE: To formally validate metrics derived from conventional MRI as surrogate endpoints for relapse rate in MS. BACKGROUND: Although metrics derived from MRI are used widely in clinical trials of MS, a formal statistical validation of MRI metrics as surrogate endpoints for clinical outcome in MS is lacking. METHODS: A validation procedure was applied to clinical and MRI data collected in the context of a randomized, double-blind, placebo-controlled trial of glatiramer acetate in patients with relapsing-remitting MS. The four Prentice operational criteria were applied to assess surrogacy for the number of new enhancing lesions, the percentage change of T2 lesion volume, and a composite MRI score based on these two metrics. RESULTS: The results of this analysis show that all three MRI measures considered by the authors had a behavior compatible with the Prentice criteria for valid surrogates. The composite MRI score correlated with relapses and accounted for much of the treatment effect on relapse rate. CONCLUSIONS: This preliminary study suggests that conventional MRI metrics might serve as valid surrogate endpoints in MS trials with glatiramer acetate or treatments thought to have a similar mode of action.
RCT Entities:
OBJECTIVE: To formally validate metrics derived from conventional MRI as surrogate endpoints for relapse rate in MS. BACKGROUND: Although metrics derived from MRI are used widely in clinical trials of MS, a formal statistical validation of MRI metrics as surrogate endpoints for clinical outcome in MS is lacking. METHODS: A validation procedure was applied to clinical and MRI data collected in the context of a randomized, double-blind, placebo-controlled trial of glatiramer acetate in patients with relapsing-remitting MS. The four Prentice operational criteria were applied to assess surrogacy for the number of new enhancing lesions, the percentage change of T2 lesion volume, and a composite MRI score based on these two metrics. RESULTS: The results of this analysis show that all three MRI measures considered by the authors had a behavior compatible with the Prentice criteria for valid surrogates. The composite MRI score correlated with relapses and accounted for much of the treatment effect on relapse rate. CONCLUSIONS: This preliminary study suggests that conventional MRI metrics might serve as valid surrogate endpoints in MS trials with glatiramer acetate or treatments thought to have a similar mode of action.
Authors: Frederik Barkhof; Jack H Simon; Franz Fazekas; Marco Rovaris; Ludwig Kappos; Nicola de Stefano; Chris H Polman; John Petkau; Ernst W Radue; Maria P Sormani; David K Li; Paul O'Connor; Xavier Montalban; David H Miller; Massimo Filippi Journal: Nat Rev Neurol Date: 2011-12-06 Impact factor: 42.937
Authors: T Tourdias; P Renou; I Sibon; J Asselineau; L Bracoud; M Dumoulin; F Rouanet; J M Orgogozo; V Dousset Journal: AJNR Am J Neuroradiol Date: 2010-10-21 Impact factor: 3.825
Authors: D J Rigotti; M Inglese; J S Babb; M Rovaris; B Benedetti; M Filippi; R I Grossman; O Gonen Journal: AJNR Am J Neuroradiol Date: 2007-09-24 Impact factor: 3.825