The Value of Direct-Acting Antivirals for the Treatment of Chronic Hepatitis C In An Integrated Healthcare System

Problem: Hepatitis C (HCV) affects over 3 million people in the United States. The disease is now curable with new all-oral direct-acting antiviral (DAA) therapies with clinical trial efficacy rates between 90%-100%. However, because the list prices of these drugs are prohibitively high, treatment has not been universally prescribed to all patients with chronic HCV for reasons that vary across payer and healthcare system. This dissertation explores the utilization and value of the new DAAs in the Kaiser Permanente Mid-Atlantic States (KPMAS) health care system by determining predictors of treatment initiation, effects of treatment on resource utilization and cost-effectiveness of different triaging treatment policies. Methods: The association between patient and provider characteristics and treatment initiation was evaluated with a cox-proportional hazards model. Due to the non-randomized treatment assignment and variations in treatment timing, we created a propensity score matched sample and conducted a time series analysis to assess the effect of treatment of subsequent resource utilization. Cost-effectiveness of triaging treatment approaches was evaluated using a Markov model using probabilistic sensitivity and value of information analyses. Results: Fibrosis score was not associated with the likelihood of being treated with a DAA. Older patients were more likely to be treated, while those with a history of a substance use disorder were less likely to be treated in our study sample. We did not find any differences in likelihood of treatment across race or insurance type. While we found a downward effect on the rate of post-treatment resource utilization, these effects were not statistically significant. Universal access to treatment, for patients across all fibrosis scores, was the optimal treatment strategy at the $150,000/QALY threshold. Sensitivity analyses showed these results were robust to parameter variations. Conclusions: KPMAS is providing equitable access to care across characteristics that typically induce disparities, but is uniquely positioned to enhance their linkage to care for some vulnerable patient subgroups. Longer follow-up may demonstrate more significant spillover effects as more advanced disease develops over many years. Expanding access to treatment seems to be the most efficient treatment strategy for chronic HCV from both perspectives