Should the Use of Acid Reducing Agents in Conjunction with Ribociclib be Avoided? An Integrated QbD Approach for Assessment of pH-Mediated Interaction

The objective of the study was to evaluate the possible pH-dependent interaction of ribociclib succinate with acid-reducing agents, which are concomitantly administered as supportive care medicines in cancer. Quality by Design-based analytical method development for a weakly basic drug ribociclib succinate supposedly having the characteristic ability of pH-dependent solubility was carried out for analyzing micro-dissolution experiment samples in biorelevant media to study pH-dependent interaction. An accurate and robust analytical method was developed using a three-level three-factorial box-behnken design for quantification of ribociclib succinate in micro-dissolution samples by the implementation of the Analytical Quality by Design approach. Here, pH of aqueous mobile phase and flow rate proved to be critical process parameters. The gastric compartment solubility was found to be 814.05 μg/mL, which dropped down to 494.71 μg/mL after a pH shift from pH 1.2-6.5. In the intestinal compartment, initial solubility was 717.58 μg/mL, which reduced to 463.20 μg/mL after a pH shift from 6.5 to 6.8. Concluded results state that pH shift does not impact the solubility or the absorption of the drug to a significant extent in the presence of acid-reducing agents. However, the study would prove to be a practical approach for examination of the behavior of the drugs at the initial stages.