Originally used for management of human immunodeficiency virus (HIV) infection, research studies subsequently found lamivudine to be 98% effective against the hepatitis B virus (HBV). Particularly indicated for chronic cases, especially for patients who do not respond to interferon therapy, lamivudine for hepatitis B is not recommended for the purpose of initial treatment. This medication is not a cure; it only slows the progression of liver damage. Lamivudine was approved by the U.S. Food and Drug Administration (FDA) in 1998.
Hepatitis B is a liver disease characterized by fatigue, nausea, and jaundice, which, in its acute form, lasts for a short period, causing liver cancer and failure in those affected chronically. A highly infectious disease transmitted primarily through sexual contact and intravenous drug use, HBV is up to 100 times as contagious as HIV spreading through contact with biological fluids such as blood, semen, saliva, and vaginal secretions. Over one million people have the chronic form of this disease in the United States as of 2009, while 350 million suffer worldwide, causing over 600,000 deaths each year. Although presently there is no cure, it is preventable through vaccination.
Minimizing and slowing down liver cell destruction is the chief goal of treatment for hepatitis B sufferers. Lamivudine for hepatitis B falls under the classification of antiviral drugs referred to as nucleoside reverse transcriptase inhibitors (NRTIs), developed to stop or to interfere with the replication of HBV and HIV. Typically taken orally in tablet form for a minimum of one year and often longer, effectiveness is determined by amount of hepatitis B antigen present in the blood, liver scarring, and inflammation, as well as detectable HBV levels.
While more effective drugs do exist, doctors find success with lamivudine for hepatitis B particularly for patients who do not respond well to standard interferon treatment. Lamivudine is tolerated well, as most patients do not tend to experience unpleasant side effects as they do with interferon or some of the other drugs used for HBV treatment. In addition, it is also only one of two drugs approved by the FDA for treating children infected with hepatitis B.
Development of HBV-resistance is common with lamivudine for hepatitis, rendering it ineffective in those who take it over the long-term, generally two-thirds of cases for treatment lasting over one year and 70% for five years. Due to a genetic mutation, the virus changes, becoming capable of surviving despite growth previously being inhibited by the medication. As most people are able to go into remission, relapse and recurrence of symptoms is likely once lamivudine is discontinued. Approximately 50% of patients relapse after three years of stopping the drug, causing serious complications and symptoms.