The cost of treating chronic hepatitis C with sofosbuvir/ledipasvir (Harvoni) is lower than the cost of prior interferon-based therapy with first-generation direct-acting antivirals (DAAs), in part because the newer drugs are well tolerated and require less management of side-effects, according to a Kaiser Permanente study presented at the 2016 Digestive Disease Week meeting last month in San Diego.
The advent of next-generation DAAs that can be used in interferon-free regimens has revolutionised treatment for chronic hepatitis C, making it shorter, better tolerated and much more effective. But the high cost of the new drugs has hampered widespread access, as some public payers and insurance companies have restricted treatment to sicker people. Yet despite its high cost several studies have found that treatment is cost-effective, and it may compare favourably with older options.
Lisa Nyberg of Kaiser Permanente in San Diego and colleagues used detailed cost mapping to determine the cost per cure for people with genotype 1 chronic hepatitis C treated with sofosbuvir/ledipasvir, with or without ribavirin.
The usual recommended sofosbuvir/ledipasvir treatment duration is 12 weeks, but some previously untreated people without liver cirrhosis are eligible for 8 weeks. Prior non-responders and people with cirrhosis may benefit from adding ribavirin. The researchers considered sustained virological response rates at 4 weeks post-treatment (SVR4) – a good predictor of sustained response at 12 weeks post-treatment (SVR12), which is considered a cure.
The prior standard of care – pegylated interferon, ribavirin and the first-generation HCV protease inhibitors telaprevir (Incivo) or boceprevir (Victrelis) – could cost around US$189,000 per SVR, the researchers noted as background. This was due in part to expenses associated with managing side-effects, for example erythropoietin or blood transfusions for anaemia. In addition, interferon-based therapy was not as effective as the newer DAAs so treatment costs were sometimes wasted without achieving a cure.
Dr Nyberg's team conducted a retrospective cohort study of 1262 adults treated for hepatitis C at Kaiser Permanente Southern California between November 2014 and July 2015. Cost estimates were based on current Medicare rates for services, lab tests and medical equipment and supplies. Prescription dispensing records were used to determine wholesale acquisition costs for the drugs.
They found that the overall average cost per SVR was $75,502 for people without cirrhosis and $100,518 for people with cirrhosis, but this varied by specific regimen.
For the 288 people without cirrhosis treated with sofosbuvir/ledipasvir alone for 8 weeks, the SVR rate was 97.0% and the average cost per SVR was $55,674. The small number of people with cirrhosis (n = 37) treated with this short regimen had an SVR rate of 92.5% and about the same average cost, $55,226. The five people with cirrhosis treated with sofosbuvir/ledipasvir plus ribavirin for 8 weeks had an SVR rate of 83.3% and a cost per SVR of $80,518; no participants without cirrhosis received this regimen.
For the 316 people without cirrhosis treated with sofosbuvir/ledipasvir for 12 weeks, the SVR rate was 96.9% and the average cost per SVR was $86,663. For 182 people with cirrhosis on the same regimen the SVR rate was 97.3% and the average cost was $92,873. For people with cirrhosis treated for 12 weeks with ribavirin, the SVR rate was 98.8% and the average cost was highest, at $94,531. Only a small number of people without cirrhosis (n = 48) received this regimen, with an SVR rate of 98.0% and an average cost of $80,854.
"Because of the better tolerability of the new agents and the high SVR [rate], cost per SVR using sofosbuvir/ledipasvir with and without ribavirin for the treatment of genotype 1 chronic hepatitis C in both cirrhotics and non-cirrhotics is lower than that previously reported using interferon-based treatment with and without first generation direct acting antiviral agents," the researchers concluded.
Nyberg LM et al. Cost per sustained virological response 4 (SVR4) in genotype 1 patients treated with sofosbuvir and ledipasvir with and without ribavirin. A detailed cost-mapping study. Digestive Disease Week 2016, abstract 232, 2016.