On-treatment monitoring

In contrast to IFN-based treatment regimens, intense monitoring of people undergoing DAA therapy is usually unnecessary. This simplification recognises the high efficacy of these regimens, the lack of a role for response-guided therapy and the considerably improved side effect profile. During treatment, follow-up intervals need to be established on a case-by-case basis to optimise adherence, assess adverse events and potential drug–drug interactions and monitor blood test results necessary for patient safety (see Table 4 below). All patients should be provided with contact details for a clinician to contact if problems arise in between appointments. For many people, no assessment will be required during treatment, and review at 12 weeks after completion of therapy can be organised to document SVR.

More intensive monitoring may be required in certain populations. On-treatment and end-of-treatment virological assessments may be considered if there are concerns about adherence to therapy, particularly if there are risk factors for reinfection. Low levels of HCV RNA in plasma or whole blood can be detected in up to 20% of people using sensitive PCR assays at Week 4 of treatment, but this does not predict treatment failure, nor does it require treatment extension.

Management of dose interruptions should be individualised according to duration of the interruption and the DAA therapy completed. There is limited evidence to guide treatment decisions. A practical approach is outlined in Table 4 (see below). For people with dose interruptions of ≤ 7 days, we recommend resuming DAA therapy and completing the prescribed course. This applies to multiple dose interruptions of ≤ 7 days; DAAs should be continued until all pills have been taken. For people with dose interruption of > 7 days, we make the recommendations shown in Table 4 (see below) based on the duration of DAA therapy completed. People in whom dose interruption has been identified will require more intensive monitoring and support during the remainder of their treatment course.

Patients treated with ribavirin (see Special Populations: Treatment of Decompensated Liver Disease) require monitoring of haemoglobin levels. People with hepatic decompensation should commence at a reduced dose of ribavirin (600 mg daily) and require more intensive monitoring. In this setting, more frequent liver function tests are advisable to monitor for medication adherence and early evidence of hepatic decompensation related to drug reaction. Calculation of MELD and Child–Pugh scores, as well as measurement of body weight, is useful for detecting deteriorating liver function or ascites in people with cirrhosis.

Screening for HCC is recommended at baseline for all people living with cirrhosis. We recommend ongoing surveillance with liver ultrasound every 6 months, with or without estimation of α-fetoprotein level. HCV treatment should not suspend HCC screening programs. We recommend a liver ultrasound be performed before starting DAA treatment (within 1 month before starting treatment) for all patients with cirrhosis to ensure that HCC screening remains up to date during the treatment and follow-up period.

People with HCV–HBV coinfection are at risk of HBV reactivation during DAA therapy for HCV (see Special Populations: Treatment of HCV in the setting of HBV coinfection). Specific monitoring for HBV reactivation is required. It is recommended that these people be treated by a specialist with experience in treating HCV and HBV infection.