Long-term
Efficacy and Safety of Adefovir (Hepsera) for the Treatment of Chronic Hepatitis
B in HBeAg Positive Patients By
Liz Highleyman  | Adefovir
(Hepsera) Tablet |
|
Several
oral antiviral agents exhibit good activity against hepatitis
B virus (HBV), but long-term treatment success may be limited by the emergence
of drug-resistant virus. As
reported in the September 2008 issue of Hepatology, an international team
of researchers analyzed the long-term safety and efficacy of the FDA approved
and widely used anti-HBV drug adefovir dipivoxil (Hepsera).
In
the initial stage of the study, 171 patients with hepatitis B "e" antigen
(HBeAg) positive chronic HBV infection were treated with 10 mg daily adefovir
for 48 weeks. At the end of the initial treatment period, adefovir produced significant
virological, serological, biochemical, and histological improvement compared with
placebo.
A subset of 65 patients treated with adefovir during the first
year continued on the drug and were followed for up to 5 years to assess long-term
safety and efficacy. These participants were mostly (83%) men, 74% were Asian,
23% were Caucasian, and the median age at enrollment was 34 years. The median
baseline serum HBV DNA level was 8.45 log10 copies/mL and the median baseline
alanine aminotransferase (ALT) level was 2 times the upper limit of normal.
Results
•
Among the 41 patients who remained on adefovir, at 5 years of follow-up the median
change from baseline in serum HBV DNA was 4.05 log10 copies/mL.
•
The median ALT decrease was 50 U/L.
•
58% of the continuing patients experienced HBeAg loss and 48% experienced seroconversion
by the end of the study.
•
Among 15 patients who underwent biopsies at baseline and at the end of follow-up,
67% exhibited improvement in necro-inflammation and 60% had improved fibrosis.
•
The adefovir resistance mutations A181V or N236T emerged in 13 patients undergoing
long-term follow-up; this was first observed at week 195.
•
No serious adverse events related to adefovir were observed during the follow-up
period.
Based
on these findings, the investigators concluded, "Treatment with adefovir
beyond 48 weeks was well tolerated and produced long-term virological, biochemical,
serological, and histological improvement."
Hopital Beaujon, Paris,
France; National Cheng Kung University Hospital, Tainan, Taiwan, Republic of China;
National University Health System, Singapore; Monash University and Monash Medical
Center, Melbourne, Australia; Phleger Liver Institute, Division of Gastroenterology,
David Geffen School of Medicine at UCLA, Los Angeles, CA; Gilead Sciences, Foster
City, CA.
10/03/08
Reference
P Marcellin, TT Chang,
SG Lim, and others. Long-term efficacy and safety of adefovir dipivoxil for the
treatment of hepatitis B e antigen-positive chronic hepatitis B. Hepatology
48(3): 750-758. September 2008. (Abstract). |
| |
FDA-approved
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