Hepatitis C: an economic evaluation of extended treatment with interferon.
OBJECTIVE
To re-evaluate the cost effectiveness of treating hepatitis C virus (HCV) infection with interferon alfa (IF alpha) in Australia, taking into account changes in clinical practice.


METHODS
A decision-analytic method (Markov model) was used to simulate the costs and effects of 6 months and 12 months of treatment with IF alpha versus no treatment (conventional management). Both costs and effects were modelled over 30 years.


METHODS
Published meta-analysis of the effectiveness of treatment, professional judgement about treatment protocols, scheduled medical fees, diagnosis-related costs for hospital admission, and a literature search for quality-of-life weights.


METHODS
A hypothetical cohort of 1000 patients with chronic HCV infection aged 40 years at the start of treatment.


METHODS
Incremental costs per life-year gained and per quality-adjusted life-year (QALY) gained.


RESULTS
Compared with no treatment, IF alpha treatment for 6 months results in an extra 94.2 life-years or 320.1 QALYs at an extra cost of $1.8 million (after discounting at 3%) in a cohort of 1000 patients. Discounted cost per life-year gained is $19,110, which is about a quarter of the cost reported in 1994. The discounted cost per QALY gained is $5625. Extended treatment for another 6 months results in an additional 89.0 life-years saved or 170.8 QALYs gained at an incremental discounted cost of $15,835 per life-year gained and $8250 per QALY gained.


CONCLUSIONS
The cost effectiveness of IF alpha treatment for HCV infection has improved as a result of better patient selection, cost reductions and enhanced effectiveness of extended treatment. The results are sensitive to assumptions made about quality of life and the discount rate.
Shiell
A
A
Department of Public Health and Community Medicine, University of Sydney, NSW. alans@pub.health.usyd.edu.au
Brown
S
S
Farrell
G C
GC
D000998:Antiviral Agents / Q000191:economics* / Q000627:therapeutic use*; D001315:Australia; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000191:economics*; D006801:Humans; D016898:Interferon-alpha / Q000191:economics* / Q000627:therapeutic use*; D008390:Markov Chains; D011788:Quality of Life; D019057:Quality-Adjusted Life Years
D000998:Antiviral Agents; D016898:Interferon-alpha