African-American HCV patients face significantly lower SVR rates
African-American patients were significantly less likely to achieve sustained virologic response after hepatitis C treatment with direct-acting antivirals compared with white patients, according to recently published data.
“Historically, race has played a major role in chronic hepatitis C rates and treatment responses with African-Americans being disproportionately affected,” Jihane N. Benhammou, MD, from the University of California Los Angeles, and colleagues wrote. “The disproportionate HCV infection rates in African-Americans and higher risk of developing HCC independently of fibrosis underscores the importance of understanding why these differences exist.”
Benhammou and colleagues retrospectively reviewed the treatment outcomes of 1,068 patients who underwent DAA therapy at the Veterans Affairs Greater Los Angeles Healthcare System.
Mean age was 61.8 years, 97% were men and 37.8% were African-American. Most patients had genotype 1 (83.9%) and no patients had genotype 5. Most patients received Harvoni (sofosbuvir/ledipasvir, Gilead Sciences) with ribavirin (47.8%) and most were treatment-naive (79.5%).
Overall SVR rates by ethnicity were 85% for African-Americans, 89% for white patients and 83% for Hispanics. After older therapies were excluded — including combined sofosbuvir and simeprevir with or without ribavirin and Sovaldi (sofosbuvir, Gilead Sciences) with ribavirin — the SVR rates were 87.8% for African-Americans, 92.4% for white patients and 92.4% for Hispanics.
Adjusted analysis showed that African-American ethnicity (OR = 0.43; 95% CI, 0.27-0.69) and advanced liver disease determined by a Fibrosis-4 score higher than 3.25 (OR = 0.4; 95% CI, 0.26-0.68) were significant negative predictors of SVR.
“Given previously published data suggesting that African-American patients require 12 weeks of therapy regardless of baseline viral load, we further investigated SVR12 rates for African-Americans when stratifying by duration of treatment (8 weeks and 12 weeks),” the researchers wrote.
The OR for SVR for the 159 African-American patients who received treatment for 8 weeks was 0.34 (95% CI, 0.09-1.29) compared with 0.4 (95% CI, 0.25-0.63) among those who were treated for 12 weeks. A subanalysis of African-American patients with genotype 1 resulted in an adjusted odds ratio of 0.48 (95% CI, 0.29-8) for SVR.
“These data suggest potential underlying biological differences between white people and African-Americans in medication response,” the researchers concluded. “One potential biological explanation for these observations is differences in drug metabolism, driven by the patients’ genetic background. To address this, Large Genome Wide Association Studies (GWAS) or comparing genotypes in African-Americans and white people who reached and did not reach SVR are needed.” – by Talitha Bennett
Disclosure: The authors report no relevant financial disclosures.