DEVELOPMENT AND CHARACTERIZATION OF TACROLIMUS TABLET FORMULATIONS FOR SUBLINGUAL ADMINISTRATION

Objective: The study aimed to prepare and characterize inclusion complexes of tacrolimus with β-cyclodextrin to improve its solubility and to formulate them into sublingual fast disintegrating tablets with a view to bypass the first-pass metabolism. Methods: Tacrolimus: β-cyclodextrin inclusion complexes (1:1 and 1:2 molar proportions) were prepared using the kneading method. Their characterization was accomplished by determining the drug content, solubility, Attenuated Total Reflection-Infrared Spectroscopy (ATR-IR), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), and powder X-Ray Diffraction analysis (pXRD). These were then formulated to fast disintegrating tablets and evaluated for precompression as well as post compressional characteristics. Results: SEM analysis showed the inclusion complexes as rough, non-porous, irregular surfaced aggregate particles. DSC and pXRD analyses confirm the crystallinity change and partial conversion to the amorphous form of the drug in the inclusion complexes. From the solubility studies, it was observed that both the inclusion complexes of 1:2 molar ratio (14.82±0.889 µg/ml) and 1:1 molar ratio (12.72±0.1004 µg/ml) improved the aqueous solubility to greater extents in comparison to that of the pure drug (3.05±0.121 µg/ml). All the tablet formulations showed good precompression and mechanical properties. The inclusion complex loaded tablets exhibited a superior drug release pattern when compared to tablets prepared with tacrolimus alone. The optimized formulation (TT3) showed an in vitro disintegration time of 34.33 s and a percent drug release of 97.87. Conclusion: The inclusion complex formulation combined with the sublingual route of administration can be expected to result in an improved bioavailability of tacrolimus by increasing its solubility and bypassing first-pass metabolism

PREPARATION AND CHARACTERIZATION OF TRIFLUOPERAZINE LOADED TRANSDERMAL PATCHES FOR SUSTAINED RELEASE

Objective: The purpose of the present study was to formulate and evaluate the polymeric transdermal delivery system of antipsychotic drug Trifluoperazine (TFP) for sustained drug release. Methods: A transdermal patch loaded with (TFP) was formulated by solvent casting technique. Polyvinyl pyrrolidone (PVP) K-30 and ethyl cellulose (EC) was used as a polymeric matrix with different ratios. Di n-butyl phthalate was used as a plasticizer. The parameters such as thickness, folding endurance and weight variation of the prepared patches were studied. The interaction study by attenuated total reflectance-infrared (ATR-IR) spectroscopy, X-ray diffraction and thermal analysis by differential scanning calorimetry (DSC) were performed. In vitro drug release study was performed by modified paddle over-disc technique. Results: The infrared spectroscopic study confirmed the absence of any chemical interaction between TFP and selected polymers. All the prepared formulations showed folding endurance values ranging from 130-162 and a satisfactory drug loading of 90-95%. In in vitro drug release study, formulations PE-3 and PE-4 exhibited a sustained and stable cumulative release of 54 % and 48% respectively, at the end of 24 h. The DSC and XRD analysis proved the partial conversion of the drug from crystalline to amorphous form when integrated into the polymeric matrix. Conclusion: The prepared transdermal formulations using polymers PVP and ethyl cellulose demonstrated their ability to sustain the release of TFP. The developed formulation could be exploited for multiday therapy of TFP for the effective treatment of schizophrenia with a simplified dosing regimen and enhanced patient compliance