Economic evaluation of direct-acting antivirals for the treatment of genotype 3 hepatitis C infection in Singapore

Background and aim: The prohibitively high cost of direct-acting antivirals (DAA) for hepatitis C virus (HCV) infection remains a barrier to treatment access in Singapore. We aimed to evaluate whether DAA as first-line therapy would be cost-effective for genotype 3 (GT3) HCV patients compared with pegylated interferon and ribavirin (PR).

Methods: A decision tree analysis was used to compare the costs and outcomes of DAA and PR as first-line therapy. Treatment effectiveness, defined as sustained virological response, was assessed using a retrospective cohort of treated GT3 HCV patients. Direct medical costs were estimated from the payer's perspective using billing information. We obtained health utilities from published literature. We performed extensive one-way sensitivity analyses and probabilistic sensitivity analyses to account for uncertainties regarding the model parameters.

Results: In base case analysis, first-line therapy with DAA and PR yielded quality-adjusted life years (QALYs) of 0.69 and 0.62 at a cost of USD 54 634 and USD 23 857, respectively. The resultant incremental cost-effectiveness ratio (ICER) (USD 449 232/QALY) exceeded the willingness-to-pay threshold (USD 53 302/QALY). The ICER was robust for uncertainties regarding the model parameters. The cost of DAA is the key factor influencing the cost-effectiveness of HCV treatment. At current price, DAA as first-line therapy is not cost-effective compared with PR, with or without consideration of retreatment. Threshold analysis suggested that DAA can be cost-effective if it costs less than USD 17 002 for a 12-week treatment course.

Conclusion: At current price, DAA as first-line therapy is not cost-effective compared with PR in GT3 HCV patients in Singapore.