Unsuccessful Direct Acting Antiviral Hepatitis C Treatment Among People With HIV: Findings From an International Cohort.

Background: Historically, hepatitis C virus (HCV) was difficult to treat among people with HIV. However, treatment with direct-acting antivirals (DAAs) results in 90%-95% of people being cured. There is a need to understand why a proportion of people are not cured. We aimed to examine characteristics that may indicate an increased probability of unsuccessful DAA HCV treatment.

Methods: Data were from the International Collaboration on Hepatitis C Elimination in HIV Cohorts. People who commenced DAA HCV treatment between 2014 and 2019 were included. Unsuccessful treatment was defined as a positive HCV RNA test at a person's first RNA test at least 4 weeks (SVR4+) following the end of treatment. Multivariable mixed-effects logistic regression was used to examine characteristics associated with unsuccessful treatment.

Results: Of 4468 people who commenced DAA treatment, 4098 (91.7%) had an SVR test 4+ weeks following the end of treatment, 207 (5%) of whom were unsuccessfully treated. Compared to a CD4+ cell count > 500 cells/mm, cell counts < 200 (aOR 1.81, 95%CI 1.00-3.29) and between 200 and 349 (aOR 1.95, 95%CI 1.30-2.93) were associated with increased odds of unsuccessful treatment. Among 1921 people with data on injection drug use in the 12 months prior to treatment, there was some evidence that recent injection drug use was associated with increased odds of unsuccessful treatment; however, this was not statistically significant (aOR 1.67, 95%CI 0.99-2.82).

Conclusions: The overwhelming majority of people were successfully treated for HCV. Overall, 5% of those with an SVR4+ test were unsuccessfully treated; this was more likely among people with evidence of immunodeficiency and those who reported recently injecting drugs.