Clinical

Telbivudine better than adefovir at suppressing HBV DNA

Last Updated: 2007-10-01 17:00:13 -0400 (Reuters Health)

By Anthony J. Brown, MD

NEW YORK (Reuters Health) - As a treatment for chronic hepatitis B in e antigen-positive patients, telbivudine, a thymidine nucleoside analogue, produces greater viral DNA suppression than does adefovir, an adenosine nucleotide analogue, new research shows.

"A head-to-head comparison between telbivudine and adefovir...has never been done before," lead author Dr. Henry L. Y. Chan, from The Chinese University of Hong Kong, told Reuters Health.

"We have unequivocally shown that telbivudine is more potent than adefovir in terms of viral suppression in chronic hepatitis B. Furthermore, patients who responded suboptimally to adefovir after 24 weeks will benefit from switching to telbivudine in terms of viral suppression," he said.

The findings, which appear in the October 2nd online issue of the Annals of Internal Medicine and will be published in the December 4th print edition, stem from a study of 135 treatment-naive patients who were randomized to receive telbivudine or adefovir for 52 weeks or to receive adefovir for 24 weeks and then switch to telbivudine for 28 weeks. The main outcome measure was HBV DNA suppression at 24 weeks.

Patients who received telbivudine for the full 52 weeks showed a greater reduction in HBV DNA levels than did the other two groups. Moreover, these patients were also more likely to become polymerase chain reaction-negative.

At 52-week follow-up, HBV DNA levels were lower in both groups treated with telbivudine than in the group that received adefovir for the full study period.

The occurrence and nature of adverse events were similar across the groups, with upper respiratory symptoms being the most common, followed by headache, backache, and diarrhea.

The authors note that the study was open-label and was inadequately powered to compare clinical outcomes between the groups or assess long-term efficacy.

"The take home message is that telbivudine can offer a more potent viral suppression than adefovir. Both treatment-naive patients and patients who respond suboptimally to adefovir can benefit from telbivudine," Dr. Chan concluded.

Future research questions "include the long-term benefit of telbivudine vs. other antiviral agents and how to treat telbivudine suboptimal responders. As far as I know, these studies are only at the planning stage," he added.

Ann Intern Med 2007