Development of zolmitriptan transfersomes by Box-Behnken design for nasal delivery: in vitro and in vivo evaluation

The aim was to prepare an optimized zolmitriptan (ZT)-loaded transfersome formulation using Box-Behnken design for improving the bioavailability by nasal route for quick relief of migraine and further to compare with a marketed nasal spray. Here, three factors were evaluated at three levels. Independent variables include: amount of soya lecithin (X-1), amount of drug (X-2) and amount of tween 80 (X-3). The dependent responses were vesicle size (Y-1), flexibility index (Y-2) and regression coefficient of drug release kinetics (Y-3). Prepared formulations were evaluated for physical characters and an optimal system was identified. Further, in vivo pharmacokinetic study was performed in male wistar rats to compare the amount of drug in systemic circulation after intranasal administration. Optimized ZT-transfersome formulation containing 82.74mg of lecithin (X-1), 98.37mg of zolmitriptan (X-2) and 32.2mg of Tween 80 (X-3) and had vesicle size of 93.3nm, flexibility index of 20.25 and drug release regression coefficient of 0.992. SEM picture analysis revealed that the vesicles were spherical in morphology and had a size more than 1 mu m. The formulations were found to be physically stable upon storage at room temperature up to 2months period, as there were no significant changes noticed in size and ZP. The nasal bioavailability of optimized transfersome formulation was found to be increased by 1.72 times than that of marketed nasal spray (Zolmist((R))). The design and development of zolmitriptan as transfersome provided improved nasal delivery over a conventional nasal spray for a better therapeutic effect.