The Present work was to develop a simple, fast, accurate, precise, reproducible, Reverse Phase High Performance Liquid Chromatographic Method for simultaneous estimation for Zidovudine and Efavirenz in pharmaceutical dosage forms. Chromatographic separation was done using symmetry C18 column having dimension of 150×4.6mm, having particle size of 5 μm, with mobile phase consisting of Phosphate buffer (KH2PO4 and K2HPO4) pH 3.5. pH adjusted to 3.5 with orthophosphoric acid and methanol (70:30 %v/v), flow rate was adjusted to 1.0 ml/min and detection wavelength at 260nm. The retention times (RT) of Zidovudine and Efavirenz was found to be 2.463 and 3.762mins. The proposed method has been validated for accuracy, precision, linearity, robustness and range was within the acceptable limit according to ICH guidelines. Linearity for Zidovudine and Efavirenz was found in range of 20ppm-100ppm.The correlation coefficient was found to be 0.999 and 0.999(r2 ≤0.999%) ,intermediate precision was found to be 1.3 for Zidovudine and 0.4 for Efavirenz. The repeatability studies were recover as 0.3% for Zidovudine and Efavirenz, then %recoveries for Zidovudine 98.4% and Efavirenz 99.0%, The method was found to be robust even by change in the mobile phase ±10% and in less flow condition. The developed method can be successfully employed for the routine analysis of Zidovudine and Efavirenz in pharmaceutical dosage forms.
