Published: 12 May 2017
Safety Information
Early Warning System - Monitoring Communication
Direct-acting antiviral (DAA) regimens and liver failure
12 May 2017
Direct-acting antiviral (DAA) regimens are used for the treatment of chronic hepatitis C infection. These medicines are relatively new and their safety is being closely monitored by Medsafe.
Assessing the role of DAA regimens in liver failure in patients with chronic hepatitis C is complex, particularly because patients often have advanced liver disease and/or cirrhosis before starting DAA treatment even if they are not experiencing symptoms. In addition, some DAAs such as Harvoni and Sovaldi are indicated for use in patients with advanced liver disease and decompensated cirrhosis. Therefore, it is difficult to know if any change in a patient’s liver disease is related to the natural course of hepatitis C virus (HCV) infection or due to HCV treatment. It is possible that potential hepatotoxicity of DAAs is related to a specific DAA or DAA regimen rather than a class effect.
The Centre for Adverse Reactions Monitoring (CARM) has received five case reports of liver failure where the reported suspect medicine included a DAA regimen. All five cases were in patients with cirrhosis. The DAA regimen reported in these cases was Viekira Pak-RBV. Viekira Pak and Viekira Pak-RBV are the most easily accessible DAA regimens in New Zealand.
Products Affected
There are a number of DAAs approved for use (Table 1). DAAs work by blocking viral reproduction of HCV. All DAAs are taken orally and treatment duration usually ranges from 12 to 24 weeks.
DAAs have cure rates of about 90% and have fewer side effects compared to previous hepatitis C treatment regimens containing interferon[1]
Table 1: Direct-acting antivirals approved and available for use in New Zealand (as at 1 March 2017)
| Product name | Active ingredients | Sponsor |
|---|---|---|
| Viekira Pak | ombitasvir/paritaprevir/ritonavir copackaged with dasabuvir | AbbVie |
| Viekira Pak-RBV | ombitasvir/paritaprevir/ritonavir copackaged with dasabuvir and ribavirin | AbbVie |
| Harvoni | ledipasvir/sofosbuvir | Gilead |
| Sovaldi | sofosbuvir | Gilead |
| Daklinza | daclatasvir | Bristol-Myers Squibb |
| Sunvepra | asunaprevir | Bristol-Myers Squibb |
| Zepatier | elbasvir/grazoprevir | Merck Sharp & Dohme |
Additional Information
HCV causes both acute and chronic hepatitis. Approximately 50,000 people in New Zealand have chronic hepatitis C and only 50% of these people know that they have it because many people have no symptoms[2]. Without treatment, patients with chronic hepatitis C can develop liver cirrhosis, liver failure and liver cancer[1].
Patients with chronic hepatitis C can have liver disease that ranges from mild fibrosis to compensated cirrhosis, decompensated cirrhosis and liver cancer[1]. Between 15% and 30% of patients with chronic hepatitis C will develop cirrhosis within 20 years and some will progress to liver cancer[1].
There are restrictions on which DAA regimens can be used in patients with liver impairment depending on whether the impairment is mild, moderate or severe. Patients with cirrhosis who are being treated with Viekira Pak or Viekira Pak-RBV should:
- be monitored for clinical signs and symptoms of hepatic decompensation such as ascites (swelling especially of the abdomen), hepatic encephalopathy (changes in behaviour or thinking) and variceal haemorrhage (bringing up blood in cough or spit)
- have hepatic laboratory testing before starting treatment and regularly during treatment
- have their treatment discontinued if they develop evidence of hepatic decompensation.
Patients should be warned to consult their healthcare professional immediately if they have onset of fatigue, weakness, lack of appetite, nausea and vomiting, jaundice or discoloured faeces.
Detailed prescribing information can be found in data sheets. Advice on how to take DAAs and the known side effects can be found in the consumer medicine information (CMI) and data sheets.
Search for medicine information and data sheets
The overall benefit-risk balance of DAA regimens remains positive.
Regulator Actions
Medsafe is continuing to monitor reports of adverse reactions to DAAs. Medsafe will publish an updated communication if any change in the rate and pattern of occurrence of this issue is identified.
Reporting
Consumers and healthcare professionals are encouraged to send reports of suspected adverse reactions to the Centre for Adverse Reactions Monitoring (CARM)
Medsafe cannot give advice about an individual's medical condition. If you have any concerns about a medicine you are taking Medsafe encourages you to talk to your healthcare professional.
References
- World Health Organization. Guidelines for the Screening Care and Treatment of Persons with Chronic Hepatitis C Infection: Updated Version. 2016 Apr [Accessed 20 July 2016]; Available from: www.who.int/hepatitis/publications/hepatitis-c-guidelines-2016/en/ .
- Hepatitis Foundation of New Zealand. Hepatitis C. [Accessed 12 April 2017]; Available from: www.hepatitisfoundation.org.nz/hepatitis-c/.
