OBJECTIVES New Direct Antiviral Agents (DAAs) to treat hepatitis C virus (HCV) are innovative but expensive. Real-world evidence is scarce on how much new DAAs reduce downstream service spending (cost impacts) and improve health outcomes. We examined the relation between use of new DAAs, total care spending, and patient outcomes in Medicare (the federal insurance program for the elderly and disabled) in the United States.

METHODS The study population was Medicare beneficiaries with chronic hepatitis C between 2014 and 2016. The outcomes were hospitalizations, total health care spending, and death. We used ICD codes from Medicare claims data to identify HCV patients and construct outcomes. We obtained information on patient mortality from Medicare beneficiary files. We compared the outcomes in two ways: 1) between new DAA users and non-users; and 2) between those who completed therapy and those who did not after initiating a new DAA. We followed patients up to 30 months from the date of HCV diagnosis for the first analysis, and from the last date of drug use for the second analysis. We used propensity-score matching regressions adjusting for a comprehensive set of patient characteristics and individual patient fixed effects.

RESULTS New DAA users had 2.3 percentage point lower mortality during the follow-up period (p<0.01). We found significant differences in hospital admissions and total health care spending between users and non-users. Patients who completed new DAA therapy had lower mortality than incompleters during the follow-up period; however, among those who survived, completing DAA therapy did not reduce hospitalizations or health care spending.

CONCLUSIONS New DAAs prevented adverse health outcomes among chronic HCV patients who were at imminent health risks. Continuing assessment is needed to identify patient sub-groups that are most cost-effective (lowest costs needed to avert one death) to treat with new DAAs.