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 (Table 6).
All patients should be provided with contact details for a clinician to contact if problems arise in between appointments. For many people, one assessment at Week 4 of treatment will be sufficient during an 8-week or 12-week treatment course. The product information for the regimen of elbasvir plus grazoprevir recommends that liver function tests be performed at Week 8 for people treated for 12 weeks’ duration, and at Week 8 and Week 12 for those receiving 16 weeks of treatment. In people treated with elbasvir plus grazoprevir, it is reasonable to perform liver function tests at Week 8 as an alternative to Week 4.40
Patients treated with ribavirin require monitoring of haemoglobin levels. More intensive monitoring is warranted for people in whom adherence is a concern, those with risk factors for ribavirin intolerance (eg, cardiac disease) or who develop ribavirin-induced anaemia, or people with advanced liver disease (portal hypertension or hepatic decompensation). 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.
Almost all people treated with DAA regimens attain undetectable HCV RNA levels during therapy. There are no response-guided DAA treatment protocols. Therefore, routine on-treatment and end-of-treatment virological assessments are not required, but may be considered if there are concerns regarding adherence to therapy, particularly if there are risk factors for reinfection. Note that low levels of plasma HCV RNA at Week 4 of treatment can be detected in up to 20% of people using sensitive PCR assays, but this does not predict treatment failure, nor does it require treatment extension. Failure to achieve an SVR with DAA therapy is rare but may be due to poor adherence to therapy, viral relapse or, rarely, post-treatment reinfection.
Screening for HCC is recommended at baseline for all people living with cirrhosis. We recommend ongoing surveillance with liver ultrasound every 6 months. The impact of DAA treatment on HCC risk is not yet clear (see Section Direct-acting antiviral therapy and risk of hepatocellular carcinoma in people with cirrhosis). HCV treatment should not suspend HCC screening programs. We recommend a liver ultrasound be performed within 1 month of starting DAA 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 Section Special poulations: 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.