No structural, functional benefit seen in phase III trial Erythropoietin added to methylprednisolone did not improve structural or functional outcomes in visual pathways after optic neuritis, the phase III TONE trial found. Mean 26-week peripapillary retinal nerve fiber layer (pRNFL) atrophy, a structural measure, was 15.93 μm for erythropoietin add-on and 14.65 μm for placebo add-on (adjusted mean treatment difference 1.02 μm, 95% CI –5.51 to 7.55; P =0.76), reported Wolf Lagrèze, MD, of the University of Freiburg in Germany, and co-authors, in Lancet Neurology . Mean low contrast letter acuity score, a functional measure, was 49.60 for erythropoietin and 49.06 for placebo (adjusted mean treatment difference –4.03, 95% CI –13.06 to 5.01). “We obtained clear results indicating that erythropoietin confers neither structural nor functional benefits in the visual system,” Lagrèze and colleagues wrote. “Treatment estimates did not approach clinically relevant effect sizes, were not ...