Development and validation for the simultaneous estimation of rilpivirine and dolutegravir in bulk and pharmaceutical dosage forms by RP-HPLC method

A simple new novel, accurate, robust and precise RP-HPLC method was developed and validated for the simultaneous quantification of Rilpivirine and Dolutegravir in bulk and marketed tablet formulations.

The method development was carried out by using INERTSIL ODS column (250×4.6mm, 5μm), by isocratic approach using a mixture of Phosphate Buffer (pH 6.8): Acetonitrile in the ratio of (35: 65) as mobile phase. The flow rate was 1.0 ml/min, 259 nm as detection wavelength.

The retention time of 3.285 min was observed for Dolutegravir and 4.635 min for Rilpivirine. Dolutegravir percentage purity was 99.97% and 100.63% for Rilpivirine. The system suitability parameters such as theoretical plate and tailing factor for Dolutegravir and Rilpivirine was observed in the range of 3209, 1.13 and 5210, 1.11and was found to be within the limit. The linear was observed in the concentration ranges of 50μg - 250μg for Dolutegravir and 30μg - 150μg for Rilpivirine and correlation coefficient (r²) value for Dolutegravir was 0.999 and 0.999 for Rilpivirine. The percentage RSD for repeatability was observed to be within the acceptance limit 0.1 and 0.7. The percentage RSD for intermediate precision was 0.4 and 0.8. The precision study was precise, robust, and repeatable. The LOD values were 3 and 3.02 and LOQ values were 9.98 and 10.01.

Hence the optimized RP-HPLC method can be used for simultaneous quantification and concurrent analysis of Dolutegravir and Rilpivirine in API and combined dosage formulations.