Currently, CHC is considered as a controllable disease since direct-acting antiviral agents (DAAs) for HCV were introduced into clinical practice. However, their commercial availability is sometimes limited. Therefore, prediction of sensitivity to various antiviral drug regimens is still important. The aim of our study was to address risk factors for the reduced treatment sensitivity in complicated CHC. Demographic characteristics, HCV genotype, polymorphism of IL-28, adiponutrin, inducible nitric oxide synthase, and endothelial receptor genes were analyzed. 432 CHC patients (i.e., naive patients, previously treated patients, patients with cirrhosis, hepatic steatosis, and chronic alcoholism) were enrolled. Treatment resistance was generally observed in patients who received pegylated interferon a plus ribavirin therapy (38% to 48%). The largest number of risk factors was demonstrated for patients with cirrhosis and chronic alcoholism. Triple treatment was unsuccessful in 25% of the patients; treatment failure was clearly genetically-basis. All but one CHC patients (n = 154) achieved SVR in DAA group.