For patients infected with hepatitis C virus (HCV), loss to follow-up (LTF) exceeds the viral failure rate among those who initiate direct-acting antiviral (DAA) therapy, according to a study published in the Journal of Viral Hepatitis. The investigators found that rates of LTF varied significantly based on HCV genotype (GT), treatment regimen, and most notably patient characteristics, establishing an argument for improved patient selection strategies.
The study, which was authored by researchers affiliated with the BC Centre for Disease Control in Vancouver, British Columbia, Canada, included data from 4477 patients from the British Columbia Hepatitis Testers Cohort, which includes information on medical visits, hospitalizations, and prescription drug use for patients tested for HCV infection since 1992. Patients who initiated DAA regimens for HCV GT1 (n=4024) and HCV GT3 (n=453) through December 31, 2017, were included in the study. The researchers used multivariable logistic regression models to assess factors associated with sustained virologic response (SVR) and LTF.
The most commonly prescribed DAA was sofosbuvir/ledipasvir with or without ribavirin (SOF/LDV±RBV), which had an SVR of 95%. The researchers observed the highest SVR (99.5%) among those treated with ombitasvir/paritaprevir/ritonavir plus dasabuvir with or without ribavirin (OBV/PTV/r+DSV±RBV).
An overall 10% LTF rate was observed, with the highest rates seen among patients with HCV GT1a treated with OBV/PTV/r+DSV±RBV (17.8%) and patients infected with HCV GT3 treated with SOF+RBV (15.7%).
Multivariate analysis revealed increased LTF rates in patients younger than 60 years, those with a history of injection drug use, those on opioid substitution therapy and/or statin therapy, and those with cirrhosis. The study authors noted that “despite the rapid advances in DAA treatments and their high effectiveness, LTF remains a significant barrier in the HCV treatment cascade and could impact the overall effectiveness of treatment.” The researchers called for further study of the psychosocial and socioeconomic factors that influence LTF in these HCV-positive subpopulations, particularly patients dealing with injection drug use problems. For patients with cirrhosis, the authors recommended further study into the impact of polypharmacy and treatment intolerance on LTF.
“Optimal patient selection and personalized case management for those with medical complications and additional supports … are needed to achieve the full benefits of effective treatments and to reduce LTF,” the researchers concluded.
The study included several limitations, including restriction of antiviral treatment for HCV infection in British Columbia during the study period to patients with fibrosis level ≥F2.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Darvishian M, Wong S, Binka M, et al. Loss to follow-up: a significant barrier in the treatment cascade with direct-acting therapies [published online October 30, 2019]. J Viral Hep. doi: 10.1111/JVH.13228