More people respond to telbivudine compared to lamivudine, study finds
WEDNESDAY, Dec. 19 (HealthDay News) -- New research suggests that a newer medication approved for treating hepatitis B is more effective than the standard treatment, lamivudine.
Additionally, the Chinese scientists found that a significantly smaller number of people developed resistance to the newer drug, known as telbivudine (Tyzeka, Sebivo).
The study, which is published in the Dec. 20 issue of the New England Journal of Medicine, found that about 8 percent more people responded to telbivudine than lamivudine, and the risk of resistance was at least halved for people taking telbivudine.
"The multiple therapeutic choices now available for hepatitis B will enhance the ability of clinicians to maintain long-term control of HBV replication, ultimately improving clinical outcomes for more patients. These results support telbivudine as an effective therapy for patients with chronic hepatitis B," the study authors wrote.
Hepatitis B is a viral infection that attacks the liver. It can be spread in many ways, including through the exchange of blood and other bodily fluids when having sex, from sharing needles, or from a mother to her baby during pregnancy, according to the U.S. Centers for Disease Control and Prevention.
As many as one third of people infected have no symptoms, according to the CDC. When symptoms do occur, they may include jaundice, fatigue, abdominal pain, loss of appetite, nausea, vomiting and joint pain. For most people, the infection is transient, lasting no more than six months or so. However, the infection can become chronic. This occurs in only about 6 percent of people over 5 who are infected with the hepatitis B virus, in about 30 percent of infected children between 1 and 5 years old, and in as many as 90 percent of babies who are infected with the virus. Chronic hepatitis B can cause scarring of the liver, which can lead to liver cancer or liver failure.
The goal of treatment is to keep levels of the hepatitis B virus as low as possible. Even if hepatitis B levels become so low that they're undetectable, long-term treatment is still required to prevent recurrence. People with hepatitis B are tested to see if they are positive or negative for E-antigens. A positive result on the E-antigen test often indicates a stronger infection, according to the Hepatitis B Foundation. Someone with a positive result is referred to as HBeAg-positive.
While there are several treatment options available to suppress the virus, one problem is that people can develop resistance to these drugs. Two new drugs, entecavir (Baraclude) and telbivudine, have been approved to treat hepatitis B since 2005.
The current study looked at how effective telbivudine is compared to the standard first-line treatment, lamivudine.
The researchers randomly assigned 1,370 people with chronic hepatitis B to receive either 600 milligrams of telbivudine or 100 milligrams of lamivudine once daily.
After a year of treatment, 75.3 percent of HBeAg-positive people taking telbivudine showed a therapeutic response versus 67 percent of those on lamivudine. In HBeAg-negative people, 64.7 percent of those on telbivudine had a response compared to 56.3 percent of those on lamivudine.
The number of study volunteers who had undetectable levels of hepatitis B virus by the end of the treatment year were much greater for those on telbivudine. In HBeAg-positive people, 60 percent achieved undetectable levels on telbivudine versus 40.4 percent for those taking lamivudine. For HBeAg-negative study participants, telbivudine brought viral levels down to undetectable for 88.3 percent compared to 71.4 percent for lamivudine. Telbivudine also got those viral levels down about five to six weeks faster, on average, than lamivudine.
Resistance developed in 5 percent of HBeAg-positive people taking telbivudine and in 11 percent of those on lamivudine. For those who were HBeAg-negative, the rates of resistance were 2.3 percent for those on telbivudine and 10.7 percent for those on lamivudine.
According to the study's authors, both medications have a similar side effect profile, and no significant differences were found in the current study volunteers.
"Telbivudine seems to work and be safe. It seems to have shown a better therapeutic and histological response," said Dr. Marc Siegel, an internist at New York University Medical Center.
"It decreases the risk of cirrhosis. It's well-tolerated, and it prevents the progression of hepatitis B better than the standard treatment right now," said Siegel.
The study authors pointed out that telbivudine hasn't yet been compared to the other new hepatitis B medication, entecavir, in a randomized clinical trial. Entecavir has also been shown to be more effective than lamivudine and creates less resistance as well.
To learn more about available treatments for hepatitis B, visit the Hepatitis B Foundation.
SOURCES: Marc Siegel, M.D., internist, New York University Medical Center, associate professor, medicine, New York University School of Medicine, and author, False Alarm: The Truth About the Epidemic of Fear; Dec. 20, 2007, New England Journal of Medicine
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