Preparation of tofacitinib sustained-release tablets using hot melt extrusion technology

This study aimed to develop a tablet that shows a drug release profile similar to the tofacitinib sustained-release tablet (Xeljanz XR®; OROS™) using hot melt extrusion technology. Tofacitinib citrate was selected as the drug. HPMCAS, HPMCP, and Kollidon VA64 were used as thermoplastic polymers to prepare a hot-melt extrudate. The extrudate was obtained from a twin screw extruder and pelletizer. The granules were compressed using a single punch press machine and then coated. TGA, DSC, XRD, FT-IR, and SEM were performed on the hot melt extrudate to understand its physicochemical properties. Dissolution tests were performed using the paddle method (USP Apparatus II). The results showed that the crystallinity state of tofacitinib changed to amorphous after the hot melt extrusion process; however, no chemical change was observed. The drug release profile was similar to that of Xeljanz XR®, which has an initial lag time owing to its OROS™ formulation; a coating process was performed to obtain a similar drug release profile. The lag time was controlled by adjusting the thickness of the coating layer. Moreover, the extrudate size and compression force during tableting did not significantly affect drug release. In conclusion, the new tofacitinib sustained-release tablet prepared using hot melt extrusion showed a drug release behavior similar to that of Xeljanz XR®.

Pharmacokinetics and Food Effect Between a 100-mg Sustained-Release Tablet and a 50-mg Immediate-Release Tablet of Vildagliptin in Healthy Subjects

Vildagliptin is one of the dipeptidyl peptidase-4 inhibitors. This study aimed to compare vildagliptin exposure between 50-mg immediate-release (IR) and 100-mg new sustained-release (SR) tablets, and evaluate the food effect on the pharmacokinetics (PKs) of vildagliptin. A randomized, open-label, 3-period, 3-treatment, 6-sequence crossover study was conducted on healthy subjects. During each period, subjects received the SR tablet either in the fasted (T1) or high-fat fed (T2) state once a day, or IR tablets administered twice a day in the fasted state (R). Blood samples for PK analysis were obtained serially up to 24 hours after dosing. Thirty-four subjects completed the study. The geometric mean ratios for the Cmax and AUC0-24h of T1 to R were 1.15 and 0.89, respectively. The corresponding values of T2 to T1 were 0.94 and 1.07, respectively. Vildagliptin exposure over 24 hours was similar between the SR and IR tablets. In addition, the PK profiles of the SR tablets were not altered by food. The SR tablets can be administered without a food effect and be an alternative option to IR tablets.

In Vitro-In Vivo Correlation of Tianeptine Sodium Sustained-Release Dual-Layer Tablets

Tianeptine tablets are currently marketed to be designed for immediate-release tablets. The tianeptine has a short half-life, making it difficult to design for sustained-release tablets and achieve bioequivalence with the tianeptine immediate-release tablet (Stablon^®). We established the in vitro-in vivo correlation (IVIVC) of three formulations of tianeptine sustained-release tablets according to their granule size. To evaluate sustained drug release, in vitro tests were performed in pH 1.2 media for 24 h. In vivo pharmacokinetic analysis was performed following oral administration of reference drug and test drug to beagle dogs. The dissolution profile revealed delayed release as the size of the granules increased. The dissolution results were confirmed in pharmacokinetic analysis, showing that the half-life was delayed as granule size increased. The final formulation and reference drug showed an equivalent area under the curve (AUC). Through this, IVIVC was established according to the size of the tianeptine sodium granules, which is the purpose of this study, and was used to predict in vivo pharmacokinetics from the formulation composition. This approach may be useful for determining optimal formulation compositions to achieve the desired pharmacokinetics when developing new formulations.

Proniosomal Telmisartan Tablets: Formulation, in vitro Evaluation and in vivo Comparative Pharmacokinetic Study in Rabbits

Objective

The purpose of this study was to prepare proniosomal vesicles of Telmisartan (TEL) to be compressed into tablets which will be further evaluated in vitro and in vivo.

Materials and Methods

An experimental design was adopted using surfactants of different HLB values (span 40-brij 35), different cholesterol ratios (20–50%) and different phospholipid types (egg yolk-soyabean). Different responses were measured followed by tablet manufacturing. The highest EE was shown in F3 (85%) while the lowest value was obtained in F7 (8.4%). Finally, zeta potential results were in the range of −0.67 to −27.6 mv. Compressibility percent revealed that F5 showed an excellent flowability characteristic with a value of 9.74±1.61 while F3 and F6 showed good flowability characteristics. By the end of the release, F6 showed approximately 90% drug release.

Results

F6 was selected for the in vivo study; C_max was increased by 1.5-fold while AUC_0-∞ also increased significantly by 3-fold when compared with commercial tablet and finally, t_max was increased by 3-fold indicating sustained release pattern. The relative bioavailability was also increased by 3.2-fold.

Conclusion

The results of this study suggested that the formulation of compressed tablets containing more stable proniosomal powder extended the release of TEL and increased its bioavailability as well.

Statistical Design of Sustained-Release Tablet Garcinia cambogia Extract and Bioconverted Mulberry Leaf Extract for Anti-Obesity

Obesity is a major health concern worldwide, and it is leading to worsening disease morbidity and mortality. Herbal supplements and diet-based therapies have attracted interest in the treatment of obesity. It is known that Garcinia cambogia (GA) and mulberry leaf, which contain polyphenols, have anti-obesity activity. Herein, we developed a combined tablet consisting of GA extract and bioconverted mulberry leaf extract (BMUL) using a statistical design approach. The ratio and amount of sustained polymers were set as factors. In the cell study, the combination of GA and BMUL showed synergistic anti-obesity activity. In a statistical model, the optimized amounts of hydroxypropyl methylcellulose 2208 (HPMC 2208) and polyethylene oxide 303 (POLYOX 303) were 41.02% and 58.98%, respectively. Additionally, the selected ratio of microcrystalline cellulose (MCC) was 0.33. When the release, hardness, and friability of the GABMUL tablet were evaluated, the error percentages of the response were lower than 10%. This indicates that the GABMUL tablet was successfully prepared.

Cubosomal based oral tablet for controlled drug delivery of telmisartan: formulation, in-vitro evaluation and in-vivo comparative pharmacokinetic study in rabbits

A nanoparticulate system; cubosomes has been suggested to support the controlled release of Telmisartan (TEL), a poorly water-soluble medication. Four distinctive formulae were selected according to the results of three estimated responses. The liquid cubosomes were successfully adsorbed onto Aerosil 380 to form granules. The formulae were evaluated for their flow properties. The best granules were compressed into tablets suitable for oral administration. The tablets were evaluated for its performance. The in vivo study of the best selected cubosomal tablets was checked after oral administration in the blood of albino rabbits utilizing an HPLC method. Results revealed that the highest EE was shown in formulae C5 (59.68 ± 1.3). All the prepared formulae had particle size less than 500 nm with PDI < 0.5 and the highest zeta potential results were observed in C5, C7, C9, C11 and C12 (>30 mv). A7 and A9 prepared using Aerosil 380 showed a perfect flowability. After 1 h of dissolution testing, the commercial product showed a 66% drug release while the release of all cubosomal formulae didn't exceed 35% during the first hour reaching a 85% of the drug released at the end of 24 h. A7 was selected for the in vivo study; T_max of TEL absorption is increased for cubosomal formula by three folds indicating sustained release pattern. The relative bioavailability is also increased by 2.6 fold. The investigation proposed the rationality of cubosome to figure an effective controlled release tablets to improve its bioavailability and expand its activity.

Inhibition of proteases activity in intestine needs a sustainable acidic environment rather than a transient

α-Chymotrypsin (α-CT) and trypsin are important components of the enzymatic barrier. They could degrade the therapeutic proteins and peptides, inhibit their activity consequently, and thereby reduce their oral bioavailability. Acidic agents, as one type of indirect protease inhibitors, have shown proof of concept in clinical trials. We report here the inactivated proteases due to acid influence can be reactivated immediately by environmental pH recovery regardless of how long the inactivation last. To keep the inactivation time of proteases for 4-5 h, we designed and prepared a sustained-release tablet containing citric acid (CA) which can effectively reduce the pH below 5.0 and maintain it for 5 h in the dissolution-reaction medium. The activity of α-CT and trypsin was quantified by analyzing the residual amount of their respective substrates BTEE and TAME. More than 80% of the substrates were survived in 5.0 h of incubation, whereas the common tablet inhibited the proteases activity for only two hours in the same experimental medium. It indicates that the sustained-release tablet loaded with CA can efficiently inhibit the α-CT and trypsin activity longer than the common tablet. The results will be beneficial for designing and formulating the peroral administration of peptide and protein drugs.