Does
SVR after Treatment with Pegasys/ribavirin Constitute a Cure for Chronic Hepatitis
C?
By
Ronald Baker, PhD The
current standard of care for treatment of chronic hepatitis C is combination therapy
with pegylated
interferon plus ribavirin, which produces a sustained
virological response (SVR) in up to 66% of patient
with HCV monoinfection (in HIV-HCV
coinfected patients, SVR rates are considerably
lower). SVR is defined
as undetectable HCV viral load
in the blood 6 months following completion of treatment, which typically lasts
24 weeks for patients with HCV genotypes 2 or 3 and 48 weeks for those with genotypes
1 or 4. It
is widely acknowledged that a small percentage of patients who achieve SVR may
relapse and experience a return
of detectable HCV RNA, but there are few data on this rare phenomenon. To gain
more information on the durability of SVR, researchers conducted a multi-national
trial of patients who participated in 9 randomized trials of pegylated
interferon alfa-2a (Pegasys) as monotherapy or Pegasys
in combination with ribavirin (Copegus). Patients
who were HCV RNA negative (< 50 IU/mL) at the final assessment of HCV viral
load in these trials were eligible for the long-term follow-up study. Serum HCV
RNA levels were then determined annually for 5 years from the date of last treatment.
Results to date were presented at the 42nd Annual Meeting of the European Association for the Study of the Liver this month in Barcelona, Spain. Results
- 997 patients are in long-term follow-up:
- 163 HCV monoinfected patients treated with Pegasys monotherapy;
- 741 HCV monoinfected patients treated with Pegasys plus
ribavirin;
- 93 HIV-HCV coinfected patients treated with either Pegasys
monotherapy or combination therapy.
- The overwhelming majority of patients (989 out of 997,
or > 99%) remained HCV RNA negative a mean of 4.1 (range 0.4-7) years after
stopping therapy, an outcome the researchers regard as a cure.
- 8 patients became HCV RNA positive between 1.1 and 2.9
(mean 2) years after completing treatment.
- There were no consistent patterns in baseline parameters,
age, sex, or HCV genotype among these 8 patients, and none
showed evidence of liver
cirrhosis.
- 2 of the relapsing patients had low baseline viral loads
(< 400,000I U/mL), while the rest had baseline viral loads ranging from 700,000-12
million IU/mL.
- It is unknown whether these incidents represent re-infection
or true “relapse.”
According to the study authors, “These results confirm the durability of an SVR
following treatment with peginterferon alfa-2a alone or in combination with ribavirin
in > 99% of patients with chronic hepatitis C, an outcome that may be considered
a cure.”
Table
 University
of Calgary, Calgary, Alberta, Canada; National Taiwan University Hospital, Taipei,
Taiwan-ROC.; Virginia Commonwealth University Medical Center, Richmond, VA; Royal
Brisbane Hospital, Herston, Queensland, Australia; Hopital Hotel Dieu, Clermont-Ferrand,
France; Hospital General De Valencia, Valencia, Spain; Roche, Nutley, NJ. Other
articles on Pegasys and Pegasys/Copegus) posted on HIV and Hepatitis.com 04/20/07
Reference
M
G Swain, M-Y Lai, M L Shiffman, and others. Durable Sustained Virological Response
after Treatment with Peginterferon Alfa-2 a (Pegasys) Alone or in Combination
with Ribavirin (Copegus): 5-year Follow-up and the Criteria of a Cure. 42nd Annual
Meeting of the European Association for the Study of the Liver. April
11 - 15, 2007, Barcelona,
Spain.
Abstract 1.
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