Adefovir (Hepsera) Therapy for Chronic Hepatitis B
Adefovir is a nucleotide analogue that received FDA approval for treatment of chronic hepatitis B in September 2002. The standard dose is one 10 mg pill each day. Studies have shown that treating HBeAg-patients for one year with adefovir results in an approximately 12 percent seroconversion rate (eradication of HBeAg and formation of HBeAb). And HBVDNA will drop to less than 400 copies/mL in approximately 21 percent of people. Significant improvement in liver inflammation and scarring (on liver biopsy specimens) has also been demonstrated. It appears that adefovir alone may be as effective as adefovir in combination with lamivudine. Efficacy has also been demonstrated as to HBeAg negative patients. Within this patient group after 48 weeks of therapy with adefovir, ALT levels normalize in approximately 72 percent of people, HBVDNA becomes nondetectable in 51 percent of people and inflammation and scarring of the liver improve in 64 percent of patients. For treatment of HBV, adefovir appears to have the same advantages over interferon as lamivudine. For example, adefovir treatment achieves results similar to lamivudine for both HBeAg positive and HBeAg negative (pre-core mutants) people. Furthermore, neither race nor hepatitis B genotype have a significant impact on the efficacy of adefovir.
A major advantage of adefovir over lamivudine is that adefovir does not lead to the development of drug-resistant mutations. Adefovir has the ability to eradicate HBV DNA in people who have developed lamivudine-resistant mutations. This applies even to those people who developed these mutations after liver transplantation.
Once treatment with adefovir is discontinued, most people will relapse. Thus, going forward, long-term adefovir treatment will probably become the standard of care. So far, studies of people using adefovir for approximately three years have not noted any adverse consequences such as drug-resistant HBV mutant formation, severe side effects or damage to other organs. The major side effect of adefovir is kidney damage, but this appears to be associated with dosages higher than 10 mg/day.
Lamivudine and Adefovir Combination Therapy
Studies combining lamivudine and adefovir are currently ongoing. Preliminary results appear promising. Patients who develop lamivudine-resistant HBV should not be treated with a combination of lamivudine and adefovir, but should discontinue lamivudine and be treated with adefovir alone.
All contents of this article are Copyright © Melissa Palmer, MD
Melissa Palmer, MD is the author of " Dr. Melissa Palmer's Guide of Hepatitis and Liver Disease". (Published 2004. Penguin Putnam).
Dr. Palmer is an internationally renowned hepatologist who has been practicing medicine since 1985. Prior to 2012, she maintained perhaps the largest medical practice devoted to liver disease in the United States. Dr. Palmer is Clinical Professor of Medicine at New York University Medical Center. Dr. Palmer graduated from Columbia University with a B.A. and was trained in hepatology (as well as medical school) at the Mount Sinai School of Medicine in New York City.
Dr. Palmer is Board Certified in Gastroenterology and in Internal Medicine.
She has authored numerous scientific publications in the field of hepatology in such peer-reviewed journals as Hepatology, Gastroenterology, Seminars of Liver Disease, Transplantation and Archives of Internal Medicine.
She is frequently called upon by the media for her opinion on various topics related to liver disease. Dr. Palmer has appeared many times on television as a liver disease expert and has been quoted in such publications as TIME magazine, Cosmopolitan magazine, Prevention magazine, the Los Angeles Times, and Newsday. She also has appeared in numerous videos and CD-Roms aimed at educating doctors and the public about hepatitis C and other liver diseases, such as primary biliary cirrhosis. Dr. Palmer lectures to the medical and general public on liver disease-related topics on a regular basis.
Dr. Palmer has performed numerous clinical trials on various experimental medications for the treatment of hepatitis.
Dr. Palmer is currently available for lecturing, investor and hedge-fund consultations, consultations to industry, and media interviews and appearances-- including television. For such matters, she can be contacted through hepatitismedia@gmail.com.