Among people who start direct-acting antiviral (DAA) treatment for hepatitis C virus (HCV), a substantial proportion do not maintain all their follow-up appointments.

Publishing their findings in the Journal of Viral Hepatology, Canadian researchers analyzed data from the British Columbia Hepatitis Testers Cohort on 4,777 people who started DAAs.

The study included people with genotype 1 of HCV who were treated with Harvoni (ledipasvir/sofosbuvir), with or without ribavirin, or the Viekira regimen (ombitasvir/paritaprevir/ritonavir; dasabuvir), with or without ribavirin, and people with genotype 3 who were treated with Sovaldi (sofosbuvir) plus ribavirin through the end of 2017.

The most commonly prescribed DAA regimen was Harvoni, with or without ribavirin. Ninety-five percent of those who received this regimen achieved a sustained virologic response 12 weeks after completing therapy, considered a cure.

The highest cure rate, of 99.5%, was seen among those who received the Viekira regimen.

Four hundred fifty-three (10.1%) of the cohort members were lost to follow-up, including 17.8% of those treated with the Viekira regimen and 15.7% of those with genotype 3.

The rate of being lost to follow-up was higher among those younger than 60 years old compared with people 60 years old and older as well as among those with a history of injection drug use and cirrhosis and those on medication-assisted treatment for opioid use disorder.

“Our findings indicate that loss to follow-up exceeds viral failure in HCV DAA therapy, and its rate varies significantly by genotype and treatment regimen,” the study authors concluded. “Depending on the etiology of lost to follow-up, personalized case management for those with medical complications and supporting services among [people who inject drugs] are needed to achieve the full benefits of effective treatments.”

To read the study abstract, click here.