A review of the one-year incidence of resistance to lamivudine in the treatment of chronic hepatitis B

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A review of the one-year incidence of resistance to lamivudine in the treatment

of chronic hepatitis B

Lamivudine resistance

Journal Hepatology International

Publisher Springer New York

ISSN 1936-0533 (Print) 1936-0541 (Online)

Category Review Article

DOI 10.1007/s12072-008-9105-y

Subject Collection Medicine

SpringerLink Date Tuesday, October 21, 2008

PDF (284.3 KB)HTML

Review Article

A review of the one-year incidence of resistance to lamivudine in the treatment

of chronic hepatitis B

Lamivudine resistance

Hie-Won Hann1 , Vicki L. 2 , S. Dixon3 and F. Barker3

(1) Division of Gastroenterology and Hepatology, Department of Medicine,

Jefferson Medical College, 1025 Walnut Street, Philadelphia, PA 19107, USA

(2) Writeology, 19 Riddy Lane, Bourn, Cambridge, CB23 2SP, UK

(3) GlaxoKline, 980 Great West Road, Brentford, Middlesex, TW8 9GS, UK

Received: 2 July 2008 Accepted: 14 September 2008 Published online: 21 October

2008

Abstract

Purpose The development of antiviral resistance is a recognized challenge to

successful treatment of chronic hepatitis B (CHB), but it has been difficult to

establish an accurate estimate of its incidence due to a number of factors: (a)

lack of an accepted definition of antiviral resistance; ( lack of a

standardized assay to assess resistance; and © lack of consensus on patient

selection criteria for resistance testing. Lamivudine, an effective and

well-established antiviral agent, has been reported to show one-year resistance

rates in CHB ranging from 6% to 32%, but methodologies used to calculate these

rates vary considerably. This article reviews the clinical, statistical, and

laboratory methodologies of clinical studies reporting one-year rates of

antiviral resistance to lamivudine in CHB.

Methods Studies reporting one-year resistance rates to lamivudine in CHB were

analyzed for methodologic differences and their influence on reported resistance

rates.

Results Studies using only a genotypic definition of resistance reported

one-year rates ranging from 14% to 32%. Studies assessing genotypic resistance

in patients with evidence of virologic breakthrough reported much lower one-year

resistance rates of 6.4–15.4%.

Conclusions It is important when comparing resistance rates to antiviral drugs

in CHB to consider the methodology and definition of resistance used because

this can dramatically influence the results.

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Hie-Won Hann (Corresponding author)

Email: Hie-Won.Hann@...

Vicki L.

Email: vicki.gregory@...

S. Dixon

Email: jon.s.dixon@...

F. Barker

Email: keith.f.barker@...

References

1. Lai C, Ratzui V, Yuen M-F, Poynard T. Viral hepatitis B. Lancet

2003;362:2089–2094