The availability of direct-acting antivirals is reducing disparities in the uptake of hepatitis C treatment

Improvement in treatment access for people with HIV co-infection

An analysis from British Columbia, Canada shows that older people, individuals with HIV co-infection, people with cirrhosis and – to some extent – people who inject drugs have been significantly more likely to receive direct-acting antiviral (DAA) treatments, compared to the older interferon-based treatments. The findings show that in the current era, treatment uptake has improved for groups who tended not to receive interferon-based treatments, Naveed Janjua and colleagues write in the August issue of the Journal of Viral Hepatitis.

However, individuals living in economically deprived neighbourhoods remained significantly less likely to receive treatment, although healthcare is publicly funded and free of charge to patients in British Columbia.

In the era of interferon-based treatments for hepatitis C, the rate of treatment uptake was low (below 15%) and especially so for certain population groups, including people living with HIV and people who inject drugs. Some of the barriers to treatment included increased side-effects and healthcare providers’ expectations of poor adherence. The availability of short course, highly effective and well-tolerated DAAs could be expected to remove barriers and increase treatment rates.

Glossary

adjusted odds ratio (AOR)

Comparing one group with another, expresses differences in the odds of something happening. An odds ratio above 1 means something is more likely to happen in the group of interest; an odds ratio below 1 means it is less likely to happen. Similar to ‘relative risk’. 

direct-acting antiviral (DAA)

Modern drugs for the treatment of hepatitis C, which work directly against the hepatitis C virus. They stop the virus from reproducing by blocking certain steps in its lifecycle.

pegylated interferon

Pegylated interferon, also known as peginterferon, is a chemically modified form of the standard interferon, sometimes used to treat hepatitis B and C. The difference between interferon and peginterferon is the PEG, which stands for a molecule called polyethylene glycol. The PEG does nothing to fight the virus. But by attaching it to the interferon (which does fight the virus), the interferon will stay in the blood much longer. 

multivariable analysis

Statistical technique often used to reduce the impact of confounding factors, in order to attempt to identify the real association between a factor of interest and an outcome. 

cirrhosis

Severe fibrosis, or scarring of organs. The structure of the organs is altered, and their function diminished. The term cirrhosis is often used in relation to the liver. 

Data come from a cohort of all people reported as having hepatitis C in British Columbia between 1990 and 2013, with data on drug prescriptions up to 2015. A total of 11,886 people received treatment:

  • 86.4% received an interferon-based regimen, including people receiving telaprevir or boceprevir with pegylated interferon/ribavirin.
  • 3.8% received a combination of DAAs with ribavirin or pegylated interferon/ribavirin.
  • 9.8% received DAAs only (in most cases, ledipasvir/sofosbuvir).

The main analysis compared individuals receiving DAAs only with individuals receiving older interferon-based regimens. In multivariable analysis, the odds of being treated were increased for people between 45 and 54 years (adjusted odds ratio 2.7, 95% confidence interval 1.7-4.4) and people over 55 years (aOR: 15.2, 95% CI: 9.5-24.2).

People with HIV co-infection had three times the odds of receiving DAAs (aOR: 3.0, 95% CI: 2.3-3.8). To a lesser extent, the odds of receiving DAAs were also higher for those with cirrhosis (aOR: 1.8, 95% CI: 1.5-2.2) and diabetes (aOR: 1.3, 95% CI: 1.1-1.5).

Similarly, those with a history of injection drug use had slightly higher odds of receiving DAAs (aOR: 1.3, 95% CI: 1.1-1.7), as did individuals on opioid substitution therapy (aOR: 1.3, 95% CI: 1.0-1.7).

The authors note that these findings contrast with studies from other settings, in which people with a history of substance use were less likely to receive DAA treatment. Although research has shown good adherence and virological outcomes in people who inject drugs, clinicians and policy makers may be concerned about the potential for reinfection if a person continues to inject drugs. “Changes in the cost of treatment and developing treatment programs that reduce the risk of reinfection will be needed to overcome barriers to HCV treatment with DAAs among PWIDs [people who inject drugs],” they say.

Finally, compared to patients from the most-privileged neighbourhoods, the odds of receiving DAAs were lower for patients in materially deprived neighbourhoods. Whereas the aOR for those in the second quintile was 1.0 (95% CI: 0.8-1.2), for those in the fifth quintile (the most deprived) it was 0.7 (95% CI: 0.6-0.9). This is despite free access to healthcare in British Columbia. The researchers call for interventions to reduce these inequalities.

“These findings indicate an improvement in treatment uptake in the DAA era for population groups who were traditionally not treated with interferon-based treatments,” the authors conclude. 

References

Janjua NZ et al. Shift in disparities in hepatitis C treatment from interferon to DAA era: A population-based cohort study. Journal of Viral Hepatitis 24: 624-630, 2017. (Abstract).