Asians
with Genotype 1 HCV Respond as Well as Whites to Interferon-based Therapy Research
has routinely shown that patients of African descent respond less well than Caucasians
to interferon-based therapy for
chronic hepatitis C, though the reasons for this are not fully understood.
There has been less extensive study -- and some conflicting data -- regarding
response rates in Hispanic and Asian patients. As
reported at the Digestive Disease Week 2007 meeting
last month in Washington, DC, researchers analyzed data from 3 Phase III registration
trials from the U.S., Europe, and Japan to clarify the role of ethnicity on rates
of response to 180
mcg/week pegylated interferon alfa-2a (Pegasys) plus ribavirin for
48 weeks. In the U.S. and Europe,
patients received 1000-1200 mg/day ribavirin, while
those in Japan
received 600-1000 mg/day. Pooled
data from treatment-naive, genotype 1b patients were analyzed to compare patient characteristics and determine factors
predicting sustained virological
response (SVR) using multivariate logistic regression analysis adjusted for
age, body weight, on-treatment response, and other known predictors. Results
- On average, Asian patients were
older and had lower body weight than Caucasian and black patients.
- SVR rates for Asian, Caucasian,
and black patients were 63%, 53%, and 29%, respectively.
- Multivariate logistic regression
analysis showed that ethnicity was not significantly associated with SVR (P =
0.14).
- However, rapid virological response (RVR; undetectable HCV RNA at week
4) was more strongly predictive of SVR in Caucasian and blacks than in Asians.
- Independent factors significantly
associated with SVR were:
- younger age (P = 0.0001);
- lower baseline HCV RNA (P = 0.0006);
- higher ALT (P = 0.0054).
|
|
Asian
(n=123)
|
Caucasian
(n=252)
|
Black
(n=14)
|
| Mean age,
years |
51 |
46 |
47 |
|
Men, % |
64 |
68 |
64 |
|
Mean body
weight, kg |
63 |
78 |
86 |
|
Mean ALT
quotient |
3.8 |
3.0 |
1.6 |
|
Mean log10
HCV RNA, IU/mL |
6.1 |
6.0 |
6.0 |
|
Cirrhosis,
% |
6 |
25 |
17 |
|
RVR, n (%)
|
33 (27) |
43 (17) |
1 (7) |
|
SVR, n (%)
|
77 (63) |
134 (53)
|
4 (29) |
|
SVR in patients
with RVR, n/N (%) |
26/33 (79)
|
41/43 (95)
|
1/1 (100)
|
|
SVR in patients
without RVR, n/N (%) |
51/90 (57)
|
91/204 (45)
|
3/13 (23)
|
Conclusion
“In
patients with HCV genotype 1b, SVR rates following treatment with [Pegasys] and ribavirin are higher
in Asian than in Caucasian and Black patients,” the investigators concluded. “However,
after adjusting for age and other factors, ethnicity itself does not impact treatment
response in Asians and Caucasians.” They
added that, “These results support extrapolation of clinical trial results in
Caucasians to the Asian population.” Department
of Gastroenterology and Hepatology, Musashino
Red Cross Hospital, Tokyo, Japan; Japanese Red Cross Musashino
Junior College of Nursing, Tokyo, Japan; Henry Dunant
Hospital, Athens, Greece; Roche, Nutley, NJ and Basel, Switzerland. 06/01/07 Reference
N
Izumi, SJ
Hadziyannis, A Lin, and others. Effect of Ethnicity
on Higher Sustained Virologic Response Rates in Pts
Receiving Peginterferon alfa-2a (40KD) and Ribavirin for HCV Genotype 1 Infection. Digestive
Disease Week 2007. Washington,
DC. May 19-24, 2007. Abstract
M1868. <----
DDW 2007 Main Page
|
