What is Hepsera?
Hepsera is a medicine that contains the active substance adefovir dipivoxil. It is available as white round tablets (10 mg).
What is Hepsera used for?
Hepsera is used for the treatment of chronic hepatitis B (infectious disease of the liver due to an infection with hepatitis B virus) in adult patients with:
- compensated liver disease (in which the liver functions normally, despite being damaged) with signs of active viral replication and signs of liver damage (indicated by high levels of the hepatic enzyme alanine aminotranferase (ALT) and detected by hepatic tissue examination at microscope);
- decompensated liver disease (in which the liver is damaged and does not function normally).
The medicine can only be obtained with a prescription.
How is Hepsera used?
Treatment with Hepsera should be started by a physician experienced in the treatment of chronic hepatitis B. The recommended dose is 10 mg once a day, taken with or without food. The duration of treatment varies depending on the patient's condition and the response to treatment, which must be checked every six months. In patients with kidney problems it is necessary to reduce the frequency of taking Hepsera.
Hepsera is not recommended in patients with severe kidney disease or dialysis (blood purification method); for these patients it should be used only if its potential benefits are greater than its potential risks.
Patients whose disease is caused by a resistant (unresponsive) virus to lamivudine (another antiviral medicine) should not be used alone to reduce the risk of Hepsera resistance developing. Hepsera should be given to these patients in combination with lamivudine or another treatment should be given. It is also advisable to make a change in therapy if the virus levels remain high after one year of treatment with Hepsera alone.
For more information, see the summary of product characteristics included in the EPAR.
How does Hepsera work?
The active ingredient in Hepsera, adefovir dipivoxil, is a "prodrug" that is converted into adefovir in the body. Adefovir is an antiviral that belongs to the class called "nucleoside analogues". Adefovir interferes with the action of a viral enzyme called DNA polymerase, which is involved in the formation of virus DNA. Adefovir interrupts the production of DNA by the virus, thus preventing it from multiplying and spreading.
What studies have been carried out on Hepsera?
Hepsera has been the subject of two main studies in which it was compared with a placebo (a dummy treatment). The first study involved 511 "HBeAg-positive" patients (infected with the common type hepatitis B virus), while the second involved 184 "HBeAg-negative" patients (infected with a mutated virus, which caused a form of chronic hepatitis B more difficult to treat). In both studies, efficacy was measured by evaluating the evolution of liver damage after 48 weeks of treatment by biopsy (which consists in taking a sample of liver tissue and in its microscopic analysis).
What benefit has Hepsera shown during the studies?
Hepsera was more effective than placebo in slowing the progression of liver disease. Of the patients treated with Hepsera, 53% of HBeAg-positive patients and 64% of HBeAg-negative patients had an improvement in liver damage detected by biopsy compared with 25% and 33% respectively of patients treated with placebo.
What is the risk associated with Hepsera?
The most common side effects associated with Hepsera treatment (seen in more than one in 10 patients) are an increase in creatinine (an indication of kidney problems) and asthenia (weakness). For the full list of all side effects reported with Hepsera, see the Package Leaflet.
Hepsera should not be used in patients who may be hypersensitive (allergic) to adefovir dipivoxil or any of the other ingredients.
Why has Hepsera been approved?
The Committee for Medicinal Products for Human Use (CHMP) decided that Hepsera's benefits are greater than its risks for the treatment of chronic hepatitis B patients with compensated liver disease and signs of active viral replication, persistently high serum ALT levels and histological evidence of active inflammation and liver fibrosis as well as in adult patients with decompensated liver disease. The Committee recommended that Hepsera be given marketing authorization.
More information on Hepsera:
On 6 March 2003, the European Commission issued a marketing authorization valid for Hepsera, valid throughout the European Union, to Gilead Sciences International Limited. The marketing authorization was renewed on 6 March 2008.
The full EPAR for Hepsera can be found here.
Last update of this summary: 01-2009.
