Increase in Platelet Count based on Inosine Triphosphatase Genotype during Interferon beta plus Ribavirin Combination Therapy
Journal of Gastroenterology and Hepatology, 05/24/2012
Clinical Article
Nomura H et al. – Natural interferon beta/ribavirin therapy is safe for patients with the inosine triphosphatase (ITPA)–CC genotype, even if their pretreatment platelet counts are low.
Methods- A total of 187 patients with chronic hepatitis C received pegylated interferon alpha/ribavirin or natural interferon beta/ribavirin therapy.
- Decreases in platelet counts based on ITPA genotype were investigated during treatment through 24 weeks.
- Platelet counts decreased during week 1 of pegylated interferon alpha/ribavirin therapy, but increased during week 2, after which platelet counts decreased gradually.
- Platelet counts decreased until week 4 of natural interferon beta/ribavirin therapy, after which platelet counts increased.
- Platelet counts after week 8 were higher relative to pretreatment platelet counts.
- Patients with the ITPA–CC genotype showed a smaller decrease in platelet counts during natural interferon beta/ribavirin therapy than those with the ITPA–CA/AA genotype; platelet counts after week 8 of this therapy were higher than pretreatment platelet counts, regardless of pretreatment platelet counts.
- Multivariate logistic regression analyses showed that natural interferon beta/ribavirin therapy was the only significant independent predictor for an increase in platelets through week 8.



