Development and Validation of Simultaneous Quantitative Dissolution Analysis for the Two Active Pharmaceutical Ingredients in Dapagliflozin Propanediol Monohydrate–Sitagliptin Phosphate Monohydrate Multi-Layered Tablets

Background: Recently, a combination prescription with the main ingredients sitagliptin and dapagliflozin as dipeptidyl peptidase-4 andsodium–glucose cotransporter-2 inhibitors, respectively, for the treatment of type 2 diabetes has widely been issued in hospitals. However, the development of double-layered tablets requires simultaneous quantitative dissolution tests that are significantly efficient and cost-effective. Objective: Individual analysis of the two active pharmaceutical ingredients (APIs) incurs more than twice the time and cost. Consequently, this study aimed to develop a dissolution analysis method that simultaneously quantifies the APIs dapagliflozin and sitagliptin in multilayered tablets. This simultaneous quantitative dissolution analysis can dramatically reduce analysis time and cost. Methods: For reversed-phase high-performance liquid chromatography (RP-HPLC) analysis using ultraviolet detection, a Zorbax C18 column (4.6 × 150 mm, 5 μm) was used, and the flow rate was 1.5 mL/min, injection amount 20 μL, and maximum absorption wavelength set to 205 nm. Additionally, the analysis time was set to 1.5 times the retention time of dapagliflozin Results: The retention times of dapagliflozin and sitagliptin were 11.57 and 2.56 min, respectively. Further, their relative standard deviations were 0.11% and 0.05%, respectively. Quantitative analysis using RP-HPLC confirmed no peak interference between the APIs and excipients. Both APIs exhibited linearity at a 20–120% concentration. Conclusion: The dissolution method developed in this study can quantify both APIs simultaneously, thereby reducing analysis time and cost by more than 50% and increasing efficiency in the pharmaceutical industry.