Early treatment for hepatitis C is highly cost-effective in Scotland when compared to treatment initiated at the stages of advanced fibrosis or cirrhosis, according to a cost-effectiveness analysis presented on Friday at the 2018 International Liver Congress in Paris.
The high cost of a course of direct-acting antiviral treatment and the large number of people in need of treatment has resulted in budget pressures and, in some countries, rationing of treatment to people with hepatitis C who have more advanced liver fibrosis.
Advocates for people living with hepatitis C and liver specialists have argued that although this policy may control costs in the short term, it could result in higher long-term medical costs owing to avoidable disease progression in people denied treatment when they have less advanced liver disease.
- decompensated cirrhosis
The later stage of
cirrhosis, during which the liver cannot perform some vital functions and
complications occur. See also ‘cirrhosis’ and ‘compensated cirrhosis’.
Furthermore, earlier treatment would permit the use of shorter treatment courses, so reducing the cost of treating each patient.
To test these assumptions, Medicus Economics and AbbVie, the manufacturer of the direct-acting antivirals glecaprevir/pibrentasvir (Maviret) developed a model of disease progression based on published natural history studies and applied it to the known characteristics of the population of people with diagnosed hepatitis C infection in Scotland, including demographics, disease stage and genotype. The results of clinical trials of glecaprevir/pibrentasvir were then used to simulate the effects of treatment at different stages, and the costs of treatment and medical care of liver-related conditions were used to calculate the cost-effectiveness of treatment initiated at different stages of liver disease.
These costs included the annual costs of management at different disease stages, the costs of treating decompensated cirrhosis and hepatocellular carcinoma and the cost of liver transplantation.
The model assumed that three-quarters of people were previously untreated at the time they began direct-acting antiviral treatment and that 89% of these people had F0-F2 fibrosis. Of the treatment-experienced people, 77% were assumed to have F0-F2 fibrosis. The remainder in both populations were assumed to have advanced liver disease (F3 or F4 fibrosis).
Assuming that treatment is started when liver disease is at stage F0 or F1, the lifetime risk of developing decompensated cirrhosis is just 4% but that lifetime risk rises to 11.6% for people who do not begin treatment until reaching F4 fibrosis. Even delaying treatment until F2 fibrosis is present increases the lifetime risk of decompensated cirrhosis to 8.9%.
The lifetime risks of hepatocellular carcinoma and liver-related death rise spectacularly for people who start treatment with F4 fibrosis. The lifetime risk of hepatocellular carcinoma is 35.2% and the risk of dying from any liver-related cause is 41.1% in this group of people, the model showed.
As a result, even though people with F3 and F4 fibrosis form a small proportion of the entire population with hepatitis C, the medical costs incurred by treatment deferral are large. The lifetime medical cost incurred by starting treatment at stages F0-F1 is £32,966. Waiting until stage F4 increases the cost to £60,963.
Early treatment would be highly cost-effective if initiated at either stages F0-F1 or at stages F2-F3 (incremental cost-effectiveness ratios (ICER) -£4542 and -£6777 respectively). The National Institute for Clinical Excellence in England considers an intervention to be cost-effective if the ICER is in the range £20,000 to £30,000 per quality-adjusted life year. If interventions have a negative ICER and are dominant, as in this study, they are especially cost-effective.