72-Week
Treatment More Effective than 48 Weeks for Patients with Detectable HCV Viral
Load at Week 4 By
Liz Highleyman A
majority of patients with chronic hepatitis C
who ultimately achieve sustained virological
response (SVR) to treatment experience an early decrease in HCV RNA and have
undetectable viral load by Week 4. Some studies suggest this response may be slower
in HIV/HCV coinfected individuals. Some
clinicians recommend discontinuing therapy to spare patients additional side effects
and expense if they have not achieved rapid virological response by Week 4, but
a subset of such patients do eventually achieve sustained response. As
reported in the August 2006 issue of Gastroenterology, Spanish researchers
conducted a study to explore whether prolonged treatment for 72 weeks can improve
the chances of achieving SVR in patients who still have detectable HCV RNA at
Week 4. The study
included 510 HIV negative (HCV monoinfected)
treatment-naive patients treated with 180
mcg/week pegylated interferon-alfa2a (Pegasys) plus 800 mg/day ribavirin.
After 4 weeks of therapy, 326 patients who still had detectable HCV RNA were randomly
assigned to continue treatment for a total of 48 weeks (the standard duration
of therapy for individuals with genotype
1 HCV; n = 165) or 72 weeks (n = 161). The
184 patients with undetectable HCV RNA at Week 4 were allocated into 2 groups
on the basis of genotype and baseline viral load, and were treated for a total
of 24 weeks (the standard duration for individuals with genotypes 2 or 3) or 48
weeks. Results 
The end-of-treatment response rates were similar in the Week 4 HCV RNA detectable
patients whether they were treated for a total of 48 or 72 weeks (about 60%).
However, the SVR rate (measured 24 weeks after the end of therapy) was higher
for those receiving treatment for 72 weeks compared with 48 weeks (45% vs 32%;
P = 0.01).
Looking only at the genotype 1 patients with detectable HCV RNA at Week 4, 44%
of those treated for 72 weeks achieved SVR, compared with 28% of those treated
for 48 weeks (P = 0.003).
Among the Week 4 HCV RNA undetectable patients, SVR rates were 79% in the arm
treated for 24 weeks (i.e., genotype
2 or 3) and 64% in the arm treated for 48 weeks (i.e., genotype 1).
The incidence of adverse
events was similar in all groups.
Among the Week 4 HCV RNA detectable patients, treatment discontinuation was more
frequent in the arm treated for 72 weeks compared with 48 weeks (36% vs 18%; P
= 0.0004).
Conclusion In
conclusion, the authors wrote, "Extension of treatment with peginterferon-alfa2a
plus ribavirin from 48 to 72 weeks significantly increases the rate of SVR in
patients with detectable viremia at Week 4 of treatment." This
study adds to the evidence that tailoring hepatitis C treatment on the basis of
early virological response can produce improved outcomes while minimizing unnecessary
side effects. More research is needed to determine optimal treatment duration
for HIV/HCV coinfected individuals. 08/29/006 Reference
J
M Sanchez-Tapias, M Diago, P Escartin, and others. Peginterferon-alfa2a plus ribavirin
for 48 versus 72 weeks in patients with detectable hepatitis C virus RNA at week
4 of treatment. Gastroenterology. 131(2): 451-460. August 2006. | 
