Development and Validation of Stability Indicating RP-HPLC Method for the Simultaneous Estimation of Antiretroviral Drugs by Forced Degradation Studies

Valganciclovir and Darunavir are two antiretroviral drugs that have been approved for the treatment of HIV Infection. An
error-free, accurate, precise and valid reverse-phase liquid chromatography method was developed for the quantitation of
Valganciclovir and Darunavir in its bulk form as well as in dosage form by forced degradation studies. Chromatographic
separation of these two drugs Valganciclovir and Darunavir, was achieved with an CHEMSIL ODS-C18 column (250 mm
× 4.6 mm, 5 μm) reverse-phase analytical column with a 10 min analytical run time using a mixture of Acetonitrile : Ortho
Phosphate buffer of pH 4 (60:40%v/v) as mobile phase. The mobile phase was streamed at a flow rate of 1.0 mL min-1
with a column temperature of 250 °C, and detection wavelength was carried out at 257 nm. The retention time was found
to be 4.1 min for Valganciclovir and 3.1 min for Darunavir. The linearity limit of Valganciclovir and Darunavir was found
to be in the range of 0.997 and 0.997. The method validation was carried out in terms of accuracy, linearity, precision,
specificity, LOD, LOQ as per ICH Guidelines. The results obtained from the validation parameters show that the method
developed can be useful in the quality control test of bulk and dosage forms of Valganciclovir and Darunavir. Valganciclovir and Darunavir were exposed to different stress conditions like acidic, basic, neutral, thermal and peroxide. Amongst all,the drug was found to be more degraded under acidic as well as basic degradation conditions.