P0811 : Sofosbuvir-based direct-acting antivirals treatment for elderly chronic hepatitis C patients: A cost-effectiveness analysis

Background and Aims: A relevant proportion of patients affected by Chronic Hepatitis C (CHC) is older than 65 years. In the interferon era, comorbidities and a higher susceptibility to interferon/ribavirin adverse events have historically limited treatment in these patients. Recent approval of interferon-free regimens, characterized by high efficacy and limited toxicity, provide unprecedented chances for these patients to receive curative treatments. However, the costeffectiveness of all-oral Direct-Acting Antivirals (DAAs) has not been addressed in the elderly population. We have performed a cost-effectiveness analysis taking into account the severity of liver disease, the age of the patient and the geriatric (frailty) status. Methods: A semi-Markov model of CHC natural history was built. The study focuses on CHC patients older than 65 years, stratified according to liver fibrosis (METAVIR F3 and F4), age (65 to 85 years old) and frailty phenotype defined by Fried’s (not frail, pre-frail and frail) for a total of 30 cohorts simulated. Treatment with sofosbuvir plus simeprevir (SOF/SMV) combination versus no treatment was assessed for each cohort population. The model estimated costs, Life Years and Quality Adjusted Life Years (QALY) using a lifetime time horizon and the Health System perspective. Results are presented as incremental cost-effectiveness ratios (ICERs) per QALY gained. Cost-effectiveness was defined as an ICER under the willingness-to-pay threshold of €37,000 per QALY gained. Results: At each fibrosis score, ICER increased with age and frailty index. Among patients with F3 fibrosis, ICER ranged from €13,934/QALY in not-frail 65 years old and €79,354 in frail 85 years old patients. Among F4 patients ICER ranged from €13,873/QALY in not frail 65 years old and €115,965 in frail 85 years old patients. In both F3 and F4 cohorts ICER was below €37,000/QALY up to age 80 in non-frail pts, up to age 75 in pre-frail patients, up to age 70 in frail patients. Adopting an alternative scenario with a 20% discount of SOF/SMV treatment, the number of cohort population simulated with an ICER below € 37,000/QALY increased. Conclusions: SOF/SMV treatment is cost-effective in most CHC patients older than 65 years, however a careful assessment of the patient geriatric status is mandatory. This cost-effectiveness analysis should promote a prospective clinical study to verify efficacy and side effects in elderly HCV patients.