Clinical Management of HCV - Special Populations and Remaining Gaps

With the advent of highly effective, oral direct-acting antivirals (DAAs), the type of patient with hepatitis C (HCV) infection that warrants special consideration has evolved substantially. For most patient populations, DAA treatment leads to HCV cure in most individuals who adhere to therapy, including people with compromised immune systems, acute hepatitis C virus infection, and active substance use disorder. Treatment of persons with HIV or organ transplantation typically requires attention to potential drug-drug interactions (DDIs) between DAAs and antiretrovirals or immunosuppressive agents. Tools like the Liverpool® HEP Drug Interaction Checker enable clinicians to anticipate and manage DDIs relatively easily. In some settings, clinicians debate whether to treat or wait for possible spontaneous clearance in persons with acute HCV infection; however, when prescribed, DAAs nearly uniformly prevent progression to chronic infection, rendering the individual incapable of onward HCV transmission. Similarly, active alcohol and illicit drug use do not, in and of themselves, impact the effectiveness of DAA therapy; however, substance use disorder may interfere with engagement in HCV cure and treatment adherence. Despite this potential challenge, current DAA regimens can lead to HCV cure in the setting of missed doses and early treatment discontinuation. Given the benefit of preventing HCV transmission, treating individuals with active injection drug use is an essential element of programs designed to eliminate HCV as a public health risk. Due to increased injection drug use in some regions, like the United States, the prevalence of HCV infection in children is growing due to relatively high rates of HCV infection in women of child-bearing potential. Fortunately, clinical trials demonstrate the safety and efficacy of currently recommended DAAs in children as young as three years old, providing curative therapeutic options. To prevent mother-to-child transmission of HCV, researchers are investigating the treatment of pregnant women during the third trimester, adopting strategies similar to those used to avoid the hepatitis B virus transmission. In 2022, the treatment of pregnant women represents perhaps the last remaining gap in clinical trials for hepatitis C and, in most regions, the unmet needs focus on the identification and linkage to care of infected individuals.