Formulation, Development and Evaluation of Pulsatile Tablets of Etoricoxib

Aim: This research aimed to develop a pulsatile drug delivery system (PDDS) for etoricoxib, selective COX-2 inhibitor analgesic, to address the limitations of conventional formulations by releasing the drug at specific intervals aligned with the circadian rhythm of pain. Method: Core tablets containing Etoricoxib were prepared by direct compression with varied concentrations of croscarmellose sodium as a superdisintegrant. The optimized core tablets were coated using hydrophilic (HPMC K4M) and hydrophobic (ethyl cellulose) polymers in different ratios to create press-coated pulsatile tablets with varying lag times. Physical properties hardness, thickness, friability, and disintegration, drug content uniformity, and in vitro release were evaluated. Results: The core tablets exhibited rapid drug release, with batch C3 showing 98.61% release within 60 minutes. Press-coated formulations with different polymer ratios exhibited varying lag times, with batch F3 achieving the optimal balance—providing a 4-hour lag time and 96.6% drug release over 8 hours. Stability studies confirmed the physical and chemical stability of the optimized formulation (F3) over 6 months under accelerated conditions. Conclusion: The developed press-coated pulsatile tablets of etoricoxib successfully achieved a controlled lag time and sustained drug release profile, making them suitable for chronopharmacological management of pain. Keywords: Etoricoxib, Pulsatile Drug Delivery System, Chronopharmacology, Press-Coated Tablets. etc