Berenguer et al found male sex, CD4 count <200 cells/mm3, HCV RNA viral load ≥800K IU/mL, compensated cirrhosis, and the use of sofosbuvir plus ribavirin were associated with treatment failure based on the analysis of patients in Madrid, Spain.[49] Del Bello et al found that patients receiving simeprevir/sofosbuvir/ribavirin therapy were more likely to have treatment failure.[34] Tapper et al found that presence of cirrhosis, prior treatment experience, treatment at an academic center, and treatment outside of the FDA recommendations were each associated with lower odds of achieving SVR.[50]. Here, CD4 is linked to Cirrhosis.