Cost-effectiveness of partial reimbursement for hepatitis B anti-viral drugs in Beijing, China: an analysis based on a retrospective cohort study

Abstract Background Partial reimbursement of antivirals for hepatitis B virus (HBV) was implemented in Beijing, China, on July 1, 2011. In previous studies, we found that partial reimbursement significantly improved antiviral drug use among insured patients with chronic HBV infection but not among patients who paid out-of-pocket. Also, after the new policy entecavir, a suggested first-line agene have replaced with adefivor, a predominantly used agents before reimbursement and become the most widely used drug. The aim of this study was to assess the effectiveness and cost-effectiveness of the reimbursement among patients with chronic HBV infection. Methods This retrospective cohort was based on electronic claims from Beijing You'an Hospital between Jan 14, 2008, and Dec 30, 2012. Age, sex, insurance status, antiviral drug claims, and on-study laboratory test of a retrospective cohort of 92 776 outpatients and 2774 inpatients with non-cirrhotic chronic HBV infection of Beijing residents were retrieved. We enrolled patients with chronic HBV infection who received adefovir, which was the most common used for patients with chronic HBV infection before the reimbursement, or entecavir, which was the most frequently used among insured patients after the reimbursement. Patients were not included if they were coinfected with other virus infection or severe diseases. The antiviral drug use data during an 18 month period prior to the enrollment were used to define naive patients. Medication possession ratio (MPR) was used to assess adherence, defined as the proportion of days within an observation period for which antiviral drugs were supplied. We used naive patients and applied the Markov model to assess cost-effectiveness for specific antivirals with different adherence rates. The study was approved by the Ethical Review Committee of the Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Beijing You'an Hospital of Capital Medical University. Findings Between Jan 1, 2009 and Dec 31, 2012, we enrolled 7665 outpatients who received adefivor and 5439 patients who received entecavir. MPR of adefivor remained constant in insured patients (84·4% [SD 23·1%] before reimbursement vs 85·8% [20.8%] after reimbursement), whereas the MPR of entecavir increased greatly from 79·7% (28·7%) before reimbursement to 89·1% (20·9%) after reimbursement among insured patients. The policy significantly improved adherence among insured patients compared with patients who paid out-of-pocket (odds ratio 1·6 [95% CI 1·2–2·4), even after adjusting for age, sex, disease severity, and antiviral drugs. Compared with MPR less than 0·5, naive patients with MPR of 0·8 or more had the highest HBV DNA response rate, with hazard ratio of 2·0 (95% CI 1·4–2·9) for HB e antigen positive patients and 1·6 (95% CI 1·2–2·1) for HB e antigen negative patients. Patients who adhered to entecavir treatment gained the longest quality-adjusted life years, and entecavir treatment was identified as the most cost-effectiveness option. Compared with patients who received adefovir or patients who adhered poorly to entecavir treatment, treatment among patients who adhered well to entecavir treatment had an incremental cost-effectiveness ratio, which was less than the common reference thresholds based on GDP per person (¥87 091). Interpretation For patients with chronic HBV infection, the partial reimbursement of drugs to an acceptable cost might effectively improve antiviral treatment outcomes by increasing antiviral use, especially the use of first-line drugs, as well as adherence. Funding Ministry of National Science and Technology of China (2012ZX10004904, 2013ZX10002002006002).