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Published on: May 10, 2022
ITPA polymorphism effects on decrease of hemoglobin during sofosbuvir and ribavirin combination treatment for chronic
Kei Morio1, Michio Imamura1, Yoshiiku Kawakami1
1Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan.
Inosine triphosphatase (ITPA) gene variants affect anemia risk and ribavirin (RBV) dosing during sofosbuvir treatment for hepatitis C. ITPA genotype CC patients experienced more anemia but achieved similar sustained virological response rates.
Area of Science:
- Hepatology
- Pharmacogenetics
- Virology
Background:
- Polymorphisms in the inosine triphosphatase (ITPA) gene are linked to anemia during peg-interferon/ribavirin (PEG-IFN/RBV) therapy for chronic hepatitis C virus (HCV).
- The impact of ITPA polymorphism on sofosbuvir/RBV treatment outcomes remains unclear.
Purpose of the Study:
- To investigate the influence of ITPA gene polymorphism on anemia, RBV dose reduction, and treatment response in chronic HCV genotype 2 patients receiving sofosbuvir plus RBV.
- To identify predictors of sustained virological response (SVR) in this patient cohort.
Main Methods:
- A cohort of 244 patients with chronic HCV genotype 2 received 12 weeks of sofosbuvir plus RBV.
- ITPA (rs1127354) genotyping was performed using the Invader assay.
- Multivariate regression analysis assessed factors associated with SVR12.
Main Results:
- The overall SVR12 rate was 94.7%.
- Patients with ITPA genotype CC exhibited significantly greater hemoglobin reduction and higher rates of RBV dose reduction compared to CA/AA genotypes.
- SVR12 rates were comparable between ITPA CC and CA/AA genotypes (94.7% vs. 94.4%, P=0.933).
- FIB4 index ≥3.25 and higher body weight were independent predictors of SVR12.
Conclusions:
- ITPA polymorphism significantly affects hemoglobin levels and RBV dose requirements during sofosbuvir/RBV therapy.
- Despite increased anemia risk, ITPA genotype CC patients achieve SVR rates comparable to CA/AA patients, indicating equivalent efficacy for chronic HCV genotype 2 infection.
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