Over 12 months, patients on patisiran displayed a reduction in decline from baseline in 6MWD (P = .02) and in Kansas City Cardiomyopathy Questionnaire overall summary (KCCQ-OS) score (P = .04) compared with those on placebo; however, the clinical relevance of these statistically significant but relatively small differences was not clear.32 As a result, patisiran was denied approval for treatment of ATTR-CM by the US Food and Drug Administration (FDA).33 Vutrisiran is a TTR-specific siRNA with enhanced stabilization chemistry that is administered subcutaneously every 12 weeks. The gene discussed is TTR; the disease is cardiomyopathy.