Latino Hepatitis C Patients Have a Lower Rate of Sustained Response to Pegylated interferon plus Ribavirin than Whites

By Liz Highleyman

It is well established that people of African descent generally do not respond as well as whites to interferon-based therapy for chronic hepatitis C, but outcomes for other racial/ethnic groups have not been extensively studied.

In the January 15, 2009 issue of the New England Journal of Medicine, Maribel Rodriguez-Torres and colleagues with the LATINO Study Group reported findings from the largest study to date comparing treatment response in Latino and non-Latino white patients.

Latinos are the fastest-growing minority group in the U.S., expected to reach 15% of the total population by 2010, the authors noted as background. Studies indicate that they have a higher prevalence of HCV infection, a mortality rate nearly twice that of non-Latino whites, and appear to experience more rapid liver fibrosis progression.

This prospective open-label multicenter study included 269 white Latino patients (parents and grandparents spoke Spanish as their primary language; most were from Mexico or Puerto Rico) and 300 non-Latino white treatment-naive patients with genotype 1 chronic hepatitis C; non-white Latinos were not included.

Baseline characteristics were similar overall in the Latino and non-Latino groups, but higher proportions of Latino patients were 40 years of age or younger, had a body-mass index (BMI) greater than 27 (overweight) or greater than 30 (obese), and had liver cirrhosis.

The study was non-randomized, and all participants were treated with 180 mcg/week pegylated interferon alfa-2a (Pegasys) plus 1000 or 1200 mg/day weight-adjusted ribavirin for 48 weeks.

The primary study end point was a sustained virologic response (SVR), or continued undetectable HCV RNA at 72 weeks (24 weeks after completion of therapy).

Results

The SVR rate was higher among non-Latino whites than among Latinos (49% vs 34%; P < 0.001).

Non-Latino white patients were more likely than Latinos to have undetectable serum HCV RNA at week 4 (P = 0.045) and throughout the treatment period (P < 0.001).

Latino vs non-Latino background was an independent predictor of sustained response after adjusting for differences in baseline BMI, cirrhosis, and other characteristics.

Adherence to treatment did not differ significantly between the 2 groups.

Treatment was generally well tolerated in both groups.

The most common adverse events were fatigue, fever, and flu-like symptoms.

Similar numbers of patients in both groups experienced adverse events or required dose modifications.

More than twice as many Latino patients withdrew from the study due to insufficient therapeutic response or loss to follow-up, but fewer Latinos discontinued due to adverse events.

Based on these findings, the study authors concluded, "Treatment with peginterferon alfa-2a and ribavirin for 48 weeks resulted in rates of sustained virologic response among patients infected with HCV genotype 1 that were lower among Latino whites than among non-Latino whites."

They added that, "Strategies to improve the sustained virologic response in Latinos are needed."

1/16/09

Reference
M Rodriguez-Torres, LJ Jeffers, MY Sheikh, and others (Latino Study Group). Peginterferon Alfa-2a and Ribavirin in Latino and Non-Latino Whites with Hepatitis C. New England Journal of Medicine 360(3): 257-267. January 15, 2009.

Other source
Roche. Pegasys Proven Effective as Hepatitis C Treatment for Latino Patients, According to Article in The New England Journal of Medicine. Press release. January 14, 2009 (http://www.rocheusa.com/newsroom).