Newer hepatitis drug more effective: studies

By Gene Emery

BOSTON (Reuters) – Entecavir, a new drug designed to battle
frequently fatal hepatitis B, is more effective than a rival
drug, according to a pair of research studies financed by the
drug’s manufacturer Bristol-Myers Squibb Co.

The two studies on long-term liver disease were published
in this week’s New England Journal of Medicine and found that
entecavir does a better job than GlaxoSmithKline’s drug,
Epivir.

“Entecavir seems to be an outstanding agent for treating
chronic hepatitis B,” because of its effectiveness and the low
rate at which the hepatitis B virus becomes resistant to the
drug, Jay Hoofnagle of the National Institute of Diabetes and
Digestive and Kidney Diseases wrote in a Journal editorial.

The two drugs are among five approved in the United States
to treat the often deadly illness, which can destroy the liver
and lead to liver cancer. A vaccine that prevents hepatitis B
is also available, and is routinely given to newborns in Taiwan
and China, where the illness is common.

About 1.5 million Americans carry hepatitis B, which is
spread by contaminated needles or sexual contact.

In a new study on the form of chronic hepatitis known as
HBeAg-positive, a team led by Ting-Tsung Chang of the National
Cheng Kung University Medical College in Taiwan found that 72
percent of the 314 patients treated with entecavir showed
improvement after 48 weeks of treatment. Among the patients who
were treated with Epivir, known generically as lamivudine, only
62 percent of the 314 patients improved in the same time.

Hepatitis B virus particles dropped to undetectable levels
in 67 percent of the people in the entecavir group, compared
with 36 percent of the lamivudine recipients.

A second study of 583 HBeAg-negative patients, conducted by
many of the same researchers, showed similar results.

In the United States, a month’s supply of 0.5 milligram
tablets of entecavir, sold under the brand name Baraclude,
costs about $650, four times the cost of lamivudine.

Hoofnagle warned that although the drugs work well,
treatment can still be complicated because “it is still unclear
who should be treated, with which agent (or combination of
agents), for how long,” and the best way to monitor patients.

In addition, the virus can develop a resistance to one of
the drugs. For example, after four years of taking lamivudine,
70 to 80 percent of patients become resistant to it.

“Perhaps the most promising aspect of entecavir therapy has
been the low rate of antiviral resistance,” Hoofnagle said.

And if people stop taking anti-hepatitis drugs, the disease
tends to return with renewed vigor, which can lead to death.

“Once treatment with oral antiviral agents has begun, it is
difficult to stop,” he said.