Review article: Success and failure of nucleoside and nucleotide analogues in chronic hepatitis B.
BACKGROUND
Strong suppression of viral replication and normalization of alanine aminotransferase is feasible with nucleos(t)ide analogues. It is estimated viral replication and liver inflammation can be controlled in 90% of patients with chronic hepatitis B with the current available treatments.


OBJECTIVE
To review the studies currently available on the management of chronic hepatitis B with nucleos(t)ide analogues.


RESULTS
Although very potent, nucleos(t)ide analogues are not effective in every patient. Some factors are known to influence treatment outcome, but many host and viral factors are still unknown. Stopping rules have to be defined to assess treatment efficacy in an early stage and change the regimen. Discontinuation of nucleos(t)ide analogues is often followed by reactivation of HBV. Data on the risk factors for relapse are necessary in order to decide if treatment can be safely discontinued. Another major drawback of nucleos(t)ide analogues is the emergence of resistance. The efficacy of compounds for the treatment of mutant virus and the impact of cross-resistance is largely unknown. The use of combination therapy to prevent resistance looks promising, but has to be proven.


CONCLUSIONS
HBV has become a treatable disease, however much research is needed to optimize treatment for individual patients and treatment failures.
Leemans
W F
WF
Department of Gastroenterology & Hepatology, Erasmus Medical Center, University Medical Center, Rotterdam, The Netherlands.
Ter Borg
M J
MJ
de Man
R A
RA
D000225:Adenine / Q000031:analogs & derivatives / Q000627:therapeutic use; D000998:Antiviral Agents / Q000627:therapeutic use*; D024882:Drug Resistance, Viral; D006147:Guanine / Q000031:analogs & derivatives / Q000627:therapeutic use; D019694:Hepatitis B, Chronic / Q000188:drug therapy*; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use; D009705:Nucleosides / Q000627:therapeutic use*; D009711:Nucleotides / Q000627:therapeutic use*; D063065:Organophosphonates / Q000627:therapeutic use; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*; D012307:Risk Factors; D014779:Virus Replication
D000998:Antiviral Agents; D009705:Nucleosides; D009711:Nucleotides; D063065:Organophosphonates; D018894:Reverse Transcriptase Inhibitors; D019259:Lamivudine; C413685:entecavir; D006147:Guanine; C053001:adefovir; D000225:Adenine