Abstract

DESIGN, FORMULATION AND EVALUATION OF BILAYER TABLETS CONTAINING ATORVASTATIN CALCIUM (IR) AND ATENOLOL (SR)

Chaithra R. P.*, Chethan Dixit*, Shankrayya M., Venkatesh. J. S., Pruthvi A. V., Arun Kumar M. K.

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Abstract

The present study involves the formulation and evaluation of regioselective bilayer tablets containing Atorvastatin Calcium as the immediate-release (IR) layer and Atenolol as the sustained-release (SR) layer for effective management of hyperlipidaemia and hypertension. The IR layer was developed using croscarmellose sodium to achieve rapid release of Atorvastatin, while the SR layer was optimized using a 3² factorial design incorporating varying concentrations of HPMC K100M and Xanthan gum to modulate the release of Atenolol. Preformulation studies including FTIR and DSC confirmed the absence of drug–excipient incompatibilities. Nine trial formulations (F1–F9) were evaluated for physicochemical parameters and in-vitro drug release profiles. The optimized formulation (F6) showed desirable results with drug release of 36.8% at 2 h, 73.7% at 6 h, and at 90% of 10.1 h. Drug release followed First-order and Higuchi models with non- Fickian diffusion, as indicated by the Korsmeyer–Peppas model. Stability studies confirmed the robustness of the formulation under ICH-recommended conditions. The developed bilayer tablets offer a promising approach for providing biphasic release and improving patient compliance in combination therapy.

Keywords: Atorvastatin calcium, Atenolol, Bilayer tablet, Sustained release, 3² factorial design, Drug release kinetics.