Formulation and Evaluation of Self Emulsifying Drug Delivery System (SEDDS) of a Novel Pharmacokinetic Enhancer Cobicistat

The current study aimed to formulate and evaluate the Self Emulsifying Drug Delivery System (SEDDS) of Cobicistat. Based on the solubility study results of the drug, Lemon Oil, Capryol 90 and PEG 400 were chosen as oil phase, surfactant and co-surfactant, respectively. Pseudo Ternary Phase Diagrams were developed to find the optimum Smix ratio for the formulation. Smix ratio 3:1 was chosen for formulation (F1-F9). SEDDS were formulated successfully and were found to be miscible with excipients. Formulation F5 to F9 were thermodynamically stable. Cobicistat SEDDS F6 to F9 was easily self-emulsified and had no signs of drug precipitation. In Phase Separation studies, formulated SEDDS F7 to F9 didn’t show any phase separation and were robust during dilution. SEDDS of cobicistat was easily dispersible and droplet sizes were F7 165.4 d. nm, F8 150.3 d. nm and F9 112.6 d. nm with 0.287, 1, and 0.414 PDI, respectively. On dilution with differing pH, none of the formulated SEDDS displayed any drug precipitation. The drug content of the formulated SEDDS was found to be F7 68.31%, F8 77.24%, and F9 69.33%. The optimized formulations were able to increase the cobicistat aqueous solubility up to 10 folds.