Background: Combined formulated  oral administration of Atorvastatin (ATVS) and Olmesartan (OLM) drugs to cardiovascular patients, reveals  negative results rather than its individual therapy. Which was sensitized on quantification of  bioanalytes of  plasma through LCMS/MS. Objective: Target was to trace  the marked bioanalytical variation in the blood plasma after administration of combined formulation, to investigate the post marketed rumor on its efficacy. Method:  For the study of this post marketing research, specific human patient volunteers were selected according to the required criteria along with ethics committee permission.  A sensitive, rapid and precise method was developed and validated to quantify  Aldosterone (ALD) , Angiotensin(ANG-II) and the Mevalonate (MVA) through LCMS/MS over twelve cardiovascular patients. Concentration of each bioanalytes were determined in three stages- Without drugs, with single drug (Olmesartan/Atorvastatin) and with their combination. The bioanalytical  levels were checked on correlating with patient’s physiological parameters. Result & Discussion: Comparative and correlative studies within these bioanalytes was established. The selectivity, specificity, linearity, precision, accuracy, extraction recovery, limit of detection (LOD) & limit of quantification (LOQ), stability were the necessary tools of validation of the developed methodology. And significance of each bioanalyte datas were estimated on p-values ≥ 0.001. Thus, lower value of Aldosterone and Angiotensin-II in single drug than its administered combination and equal concentration of Mevalonate in those stages, was estimated. Conclusion:  This concludes that the combined formulated cardiovascular drugs neither shows synergistic nor effective compared to a single drug. Thus, the combination of Atorvastatin & Olmesartan is non-effective. It might be reasons of competitive carrier receptor bindings in hepatic region.