Poly-pharmacy of cardiovascular drugs is a common cause of a few unexpected drug-drug interactions (DDI) which may lead to the occurrence of the adverse effects of the drugs co-administered. The High Performance Thin Layer Chromatography method was adopted for the analysis of apixaban and atorvastatin. The method validation for the individual drugs was carried out according to the ICH guidelines. The validated method was applied for the in vitro drug-drug interaction study is at the biological pH of stomach at 4.0, of blood at 7.4 and intestinal condition at 9.0. The aim of the study is to evaluate the effect of atorvastatin under the simulated conditions of the human body. The in vitro drug-drug interaction studies suggest that the drug apixaban does not have any profound change at pH 4 and 9 when present with atorvastatin. When apixaban and atorvastatin are present at a pH 7.4 the significant variation in the detector response is indicative of the decrease in the level of apixaban.