TTR and neuropathy: Patisiran 0.3 mg/kg every 3 weeks decreased serum transthyretin levels by 81% and improved neuropathy, as measured by the modified Neuropathy Impairment Score + 7 in 225 patients with hereditary transthyretin amyloidosis enrolled in the randomized, double-blind, placebo-controlled APOLLO study (N = 225)33.