OBJECTIVES: Familial Amyloidotic Polyneuropathy (FAP) is a rare, inherited, progressively debilitating disease with a high unmet medical need. The purpose of this analysis is to assess the impact of FAP on healthcare resource utilization, quality of life, employment status, and activities of daily living (ADLs). METHODS: A Phase 2 open-label extension study of patisiran in FAP patients was utilized to collect patient-reported outcomes, including EQ-5D, Rasch-built Overall Disability Scale (R-ODS), and a healthcare resource utilization questionnaire. RESULTS: The study included 27 patients, 18 males and 9 females, 29-77 years of age. Baseline data are presented for 14 patients with a Polyneuropathy Disability (PND) Score I and 13 patients with a PND Score ≥ II. Characterized by FAP Stage, 24 patients are FAP Stage 1 and 3 patients are FAP Stage 2. Two patients (PND Score ≥ II) reported a total of six hospitalizations due to FAP in the past 12 months, each for 3 or more nights in duration. Mean EQ-5D scores were 0.82 (PND Score I) and 0.74 (PND Score ≥ II). Patients reported their perceived health status on the EQ-VAS with mean scores of 75 (PND Score I) and 60 (PND Score ≥ II). Ten patients (8/10 PND Score ≥ II) reported they cannot work because of FAP. Patients also reported inability to perform various ADLs. Most commonly, 77% of patients with PND Score ≥ II cannot stand for hours (14% in PND Score I) and 69% cannot run (21% in PND Score I). CONCLUSIONS: FAP patients experience considerable burden of illness early in the course of disease and this burden increases with disease progression. The factors described will be influential in the development of a comprehensive FAP cost-consequence analysis. Additional parameters may also be needed to fully capture the totality of burden.