RP-UPLC METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION AND FORCED DEGRADATION STUDIES OF ELVITEGRAVIR, COBICISTAT, EMTRICITABINE AND TENOFOVIR DISOPROXIL FUMARATE IN SOLID DOSAGE FORM

A stability indicating method was developed and validated for simultaneous estimation of Elvitegravir, Cobicistat, Emtricitabine, and Tenofovir Disoproxil Fumarate (Tenofovir D F) in solid dosage form using RP-UPLC method. Waters Acquity UPLC system with Column Endoversilo C18 (50 × 2.1 nm, 1.8 μm) having PDA detector at 252 nm wavelength was used. Mobile phase having a mixture of 700 ml of Acetonitrile and 300 ml 0.1% Ortho Phosphoric Acid (OPA) in the ratio 70:30 v/v was used. The flow rate was set to 0.3ml/min. The retention time was obtained at 0.59 min for Elvitegravir, 2.51 min for Cobicistat, 1.48 min for Emtricitabine, and 0.73 min for Tenofovir Disoproxil Fumarate respectively with a total run time of 4 min. The linearity was calculated with correlation coefficients (r²=0.999), which were found to be within limits. The percentage recoveries of Elvitegravir, Cobicistat, Emtricitabine, and Tenofovir Disoproxil Fumarate were within the acceptance criteria. The drugs were found to be stable at forced degradation conditions, and the net degradation was found to be within limits. The developed method can be used for the quality control of the combination in the pharmaceutical dosage form.