Evaluation of Mortality During Long-Term Treatment with Tafamidis for Transthyretin Amyloidosis with Polyneuropathy: Clinical Trial Results up to 8.5 Years

INTRODUCTION: The effects of tafamidis on mortality in Val30Met and non-Val30Met patients with transthyretin amyloidosis with polyneuropathy (ATTR-PN) were evaluated. METHODS: The analyses were based on cumulative data from the Val30Met patients in the 18-month double-blind registration study and its 12-month open-label extension study, the non-Val30Met patients of the 12-month open-label study, and both patient groups in the ongoing 10-year extension study. Kaplan–Meier analyses of time to death from first treatment dose were performed. For the Val30Met group, two treatment groups were analyzed: those who received tafamidis in both the parent and extension studies (T–T) and those who received placebo in the parent study and switched to tafamidis in the extension studies (P–T). RESULTS: Kaplan–Meier estimates (95% confidence interval [CI]) were available up to 9 years for the Val30Met group, at which time 85.9% (53.1–96.4) and 91.1% (77.9–96.6) of the patients in the T–T and P–T groups, respectively, were alive. For the non-Val30Met group, estimates were available up to 8 years from the first dose, and the percentage of patients alive was 75.9% (47.7–90.2). CONCLUSION: Long-term tafamidis treatment may confer survival benefit in patients with ATTR-PN. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00409175, NCT00791492, NCT00630864, and NCT00925002.