Development and evaluation of orally disintegrating tablets of cilostazol-β-cyclodextrin inclusion complexes

Preclinical pharmacology and pharmacokinetics of curcumin tagged cilostazol nanodispersion for the management of diabetic nephropathy in wister rat model

To evaluate the therapeutic potential of curcumin tagged cilostazol solid nano dispersion in wistar rat streptozotocin-nicotinamide-induced diabetic nephropathy. Cilostazol (CLT), a Phosphodiesterase (PDE) inhibitor has an inhibitory effect on reactive oxygen species (ROS), and Curcumin (Cur), an antioxidant, and anti-inflammatory, are water-soluble. Solid Nano dispersions were developed using the "Box-Behnken Design" and emulsion solvent evaporation procedure to improve the solubility and bioavailability. Streptozotocin (SPZ) and Nicotinamide (NA) caused diabetes in Wistar rats. DN developed 30-45 days after disease induction. All rat groups underwent histological, biochemical and pharmacokinetic evaluation. The optimized batch of Cilostazol Loaded Novel Curcumin Tagged Solid Nanodispersion (CLT-15 SND) estimated renal, lipid, and cytokine profiles better than the conventional batch. CLT-15 SND, given orally to diabetic rats for 45 days, significantly lowered fasting BGL and IL-6 levels and improved lipid and kidney-profile markers and body weight compared to plain Cilostazol Loaded Solid Nanodispersion (CLT-15 WC SND). CLT-15 SND treatment groups showed decreased blood glucose by 3.38 and 9.71 percent, increased body weight by 2.81 and 5.27 percent, improved Interleukin-6 (IL-6) by 21.36 and 18.36 percent, improved urine albumin levels by 5.67 and 14.19 percent and creatinine levels by 3.125 and 37.5 percent, improved serum urea by 30.48 percent, increased serum albumin by 2.59 and 11.18 percent, and decreased creatinine and 5.03 and 8.12 percent, respectively as compared to CLT-15 WC and MP treatment animal groups. CLT and Cur reduced IL-6, kidney, and lipid markers, demonstrating their renoprotective and pancreas-protective effects. CLT and Cur's inhibition may be the mechanism.

Graphical abstract

Choc-Tadalafil Fusion: Unlocking Solubility and Taste Harmony with β-CD-Infused Medicated Chocolate

OBJECTIVE

The primary limitations of tadalafil in treating erectile dysfunction are its low solubility and unpleasant bitter taste, which ultimately result in inadequate patient adherence. The present study aimed to develop and characterize a medicated chocolate formulation containing Tadalafil and β-CD (solubility enhancer) employing the concept of Design of Experiment (DoE) using chocolate as a user-friendly excipient.

METHODS

An inclusion complex was formulated by incorporating the drug into β-CD using the kneading method for solubility improvement and also as a taste masker for Tadalafil. The ratio of drug: β-CD inclusion complex was selected based on a phase solubility study. The inclusion complex was molded into a chocolate base and optimized using the DoE approach. Further, drug excipient interaction was evaluated by DSC and FTIR study.

RESULTS

Phase solubility study suggested a 1:1 ratio of Tadalafil: β-CD for better solubility. DSC spectra suggested the conversion of crystalline structure into an amorphous state which indicates improvement of the drug solubility. DSC and FTIR studies revealed that there was no significant interaction between drug and excipients. Next, %CDR (cumulative drug release) at 30 min revealed the immediate effect of Tadalafil from chocolate formulation and free drug analysis (an unbound drug with β-CD) proved reduced bitterness of the drug in the complex. Additionally, the medicated chocolate was found to be stable at room temperature as per stability study.

CONCLUSION

β-CD was found to be a promising multifunctional excipient as a solubility enhancement carrier and taste masker for bitter-tasting drugs.

Novel bioequivalent oral disintegrating tablet of aripiprazole prepared by direct compression technique with shortened disintegration time

Herein, we aimed to formulate a novel oral disintegrating tablet (ODT) of aripiprazole (ARP) capable of rapid disintegration using a direct compression technique. Different ODTs were fabricated with directly compressible excipients, and their disintegration time, wettability (water absorption ratio and wetting time), and mechanical properties (hardness and friability) were evaluated. The optimized ODT comprised F-Melt® type C, Prosolv® SMCC HD90, and Na croscarmellose (10 mg of ARP in a 130 mg tablet). The ODT with 3.1-5.2 kp hardness exhibited rapid disintegration (14.1-17.2 sec), along with appropriate mechanical strength (friability < 0.24%). In a bioequivalent study in Korean healthy subjects (randomized, single-dose, two-period crossover design, n = 37), the novel ODT offered the equivalent pharmacokinetic profile to that of a conventional immediate release tablet (Otsuka, Abilify®, Japan), despite different disintegration and dissolution profiles. The 90% confidence intervals of the geometric mean test to reference ratios considering the area-under-the-curve and maximum plasma drug concentrations were 1.0306-11051 and 0.9448-1.1063, respectively, satisfying FDA regulatory criteria for bioequivalence. The novel ART ODT was physicochemically stable under the accelerated storage condition (40 °C, RH75%) for 24 weeks. Therefore, the novel ARP-loaded ODT is expected to be an alternative to oral ARP therapy, providing improved patient adherence.

Formulation and Quality Control of Orally Disintegrating Tablets (ODTs): Recent Advances and Perspectives

Orally disintegrating tablets (ODTs) rapidly disintegrate or dissolve in the oral cavity without using water. Demand for ODTs has increased, and the field has overgrown in the pharmaceutical industry and academia. It is reported that ODTs have several advantages over other conventional tablets. Since some of them are absorbed from the mouth, pharynx, and esophagus as the saliva passes down into the stomach, in such cases, the bioavailability of the drug improves meaningfully. Furthermore, the immediate release property of ODTs makes them a popular oral dosage form in patients with swallowing challenges, children, and for cases with a need for rapid onset of action. The current review article explains the features of active ingredients and excipients used in the formulation of ODTs, discusses multiple ODT formulation and preparation techniques with their merits and demerits, and also, offers remedies for problems associated with ODTs. Moreover, quality control steps and required considerations are presented.

Development and characterization of orodispersible film containing cefixime trihydrate

Patients suffering from dysphagia have trouble in swallowing conventional oral dosage forms and there is also risk of choking, which may cause patient noncompliance. This study aimed to develop an orodispersible film (ODF) containing cefixime trihydrate (CFX) to cope with the above-mentioned problems as well as to enhance water solubility and masking the bitter taste of the drug. The freeze-drying and kneading methods were used for the formation of inclusion complexes. The physicochemical evaluation revealed that T7 was the best film for the incorporation of pure drug and inclusion complexes. Films were further characterized for physical and mechanical properties. Drug content, dissolving time of the film and drug release tests were performed. In vivo taste and disintegration time studies were also conducted in healthy human volunteers. FTIR spectra of the individual ingredients and prepared formulations have confirmed the chemical compatibilities of the ingredients. The solubility of CFX was increased by complexation with β-CD and optimized freeze-dried inclusion complex (FD1) was selected for the formation of ODF. C4 was selected as an optimized film for the delivery of CFX as this film has released 95.52% drug at the end of 10 min. Dissolution kinetics of FD1 showed that it followed zero-order kinetics while drug release from films, exhibits first-order kinetics; however, both showed non-Fickian transport. In vivo taste evaluation revealed that taste was masked by inclusion complexation with β-CD. However, selected ingredients and employed methodology enabled to formulate film, capable of delivering taste-masked CFX with improved solubility and better patient compliance.

Fabrication and evaluation of fast disintegrating pellets of cilostazol

The present study was designed to formulate and develop fast disintegrating pellets of poorly soluble model drug (cilostazol) by reducing the proportion of micro-crystalline cellulose with pre-gelatinized starch (PGS), lactose and chitosan. The bioavailability enhancement of a model drug was achieved by preparing inclusion complex with Captisol® (Sulfobutyl Ether β cyclodextrin - SBE-β-CD). Extrusion-spheronization technique was used to formulate pellets. Placket-Burman design was used for the initial screening of most significant factors such as screen size (mm), ratio of micro crystalline cellulose: PGS + lactose + chitosan and % of HPMC which affects pellet properties. The inclusion complex of drug and Captisol^® (SBE-β-CD) was prepared by Solvent Evaporation method and were incorporated into pellets in a predefined proportion. Formulation was optimized by using 3² full factorial design, the optimized batch was selected on the basis of dependent variables such as % yield, pellet size, disintegration time and % Cumulative drug release (%CDR), the obtained results were 87.15%, 0.75 mm, 13 min and 91.024% respectively. Differential scanning calorimetry (DSC) and Fourier transform infrared spectrometry (FTIR) study revealed no significant interaction between drug and polymer. Scanning electron microscopy (SEM) confirmed uniform and spherical shaped pellets having pores on the surface which facilitates wicking action and fast disintegrating property of pellets. A design space was constructed to meet the desirable target and optimized batch. The scope of study can further extended to hydrophobic molecules which may useful due to rapid disintegration and enhanced dissolution rate.

Development and optimization of levodopa and benzylhydrazine orally disintegrating tablets by direct compression and response surface methodology

The number of Parkinson's disease (PD) patients with the advanced phase and motor fluctuations is increasing. The objective of this study is developing levodopa/benzylhydrazine orally disintegrating tablets (L/B ODTs), which would provide greater convenience and ease of use than conventional tablets for these patients. In the present study, the L/B ODTs were developed successfully with an optimized formulation using response surface methodology (RSM). The direct compression technology was employed for the preparation of L/B ODTs. Considerably shorter disintegration time and faster dissolution profile were obtained under the optimum formulation with microcrystalline cellulose 25.7%, cross-polyvinylpyrrolidone 6.22% and Sodium carboxymethyl starch 5.36%. The content uniformity (%) of levodopa and benzylhydrazine was 50 ± 1.4% and 14.25 ± 0.6%, respectively. Thickness, friability, hardness and wetting time were 2.8 ± 0.05 mm, 0.46 ± 0.21%, 5.42 ± 1.1 kp and 31.2 ± 2.1 s, respectively, and all of data well comply with the General Principles of the Chinese Pharmacopeia. Mannitol of 22% in formulation could bring a pleasant taste: sweet, cool and refreshing. Almost all the volunteers felt that the ODTs had good taste, no roughness, and no gritty feeling, indicating that the ODTs prepared had good palatability, so patients will have good compliance when taking medicine.

Comparison of a revaprazan-loaded solid dispersion, solid SNEDDS and inclusion compound: Physicochemical characterisation and pharmacokinetics

The aim of this research was to compare three strategies for enhancing the solubility of poorly water-soluble revaprazan hydrochloride: solid dispersion, solid SNEDDS and inclusion compound. The influence of polymers, surfactants and oils on the drug solubility was assessed, and via the chosen carriers, the three types of formulations were prepared utilising spray drying technique. Their physicochemical properties, solubility, dissolution and pharmacokinetics in rats were performed compared with revaprazan powder. Among the liquid SNEDDS formulations assessed, the compositions of revaprazan, peceol, Tween 80 and Labrasol (10:15:55:30, weight ratio) provided the smallest emulsion size. Moreover, this liquid SNEDDS and dextran were suspended/dissolved in distilled water, and spray-dried, producing an optimal revaprazan-loaded solid SNEDDS. The appropriate solid dispersion and inclusion compound were composed of revaprazan, hydroxypropylmethylcellulose and cremophor A25 (5:1.4:5.6) and drug and hydroxyl-β-cyclodextrin (2.5:8.77), respectively. The crystalline drug was converted to an amorphous state in all formulations. In the solid dispersion, the drug was attached to the hydrophilic carrier. The solid SNEDDS and inclusion compound contained aggregate microspheres and separate microspheres, respectively. All formulations significantly increased the drug solubility, dissolution, plasma concentration and AUC compared with revaprazan powder. These properties were ranked in the order solid dispersion ≥ solid SNEDDS > inclusion compound. Particularly, the solid dispersion improved about 9500-fold drug solubility and 10-fold oral bioavailability. Thus, the improved properties were considerably dependent upon these techniques, although all of the techniques employed similar mechanisms. Among the strategies checked, the solid dispersion system would be recommended as an oral revaprazan-loaded pharmaceutical product.

Improved oral absorption of cilostazol via sulfonate salt formation with mesylate and besylate

Objective

Cilostazol is a Biopharmaceutical Classification System class II drug with low solubility and high permeability, so its oral absorption is variable and incomplete. The aim of this study was to prepare two sulfonate salts of cilostazol to increase the dissolution and hence the oral bioavailability of cilostazol.

Methods

Cilostazol mesylate and cilostazol besylate were synthesized from cilostazol by acid addition reaction with methane sulfonic acid and benzene sulfonic acid, respectively. The salt preparations were characterized by nuclear magnetic resonance spectroscopy. The water contents, hygroscopicity, stress stability, and photostability of the two cilostazol salts were also determined. The dissolution profiles in various pH conditions and pharmacokinetic studies in rats were compared with those of cilostazol-free base.

Results

The two cilostazol salts exhibited good physicochemical properties, such as nonhygroscopicity, stress stability, and photostability, which make it suitable for the preparation of pharmaceutical formulations. Both cilostazol mesylate and cilostazol besylate showed significantly improved dissolution rate and extent of drug release in the pH range 1.2–6.8 compared to the cilostazol-free base. In addition, after oral administration to rats, cilostazol mesylate and cilostazol besylate showed increases in C_max and AUC_t of approximately 3.65- and 2.87-fold and 3.88- and 2.94-fold, respectively, compared to cilostazol-free base.

Conclusion

This study showed that two novel salts of cilostazol, such as cilostazol mesylate and cilostazol besylate, could be used to enhance its oral absorption. The findings warrant further preclinical and clinical studies on cilostazol mesylate and cilostazol besylate at doses lower than the usually recommended dosage, so that it can be established as an alternative to the marketed cilostazol tablet.

Formulation development and systematic optimization of stabilized ziprasidone hydrochloride capsules devoid of any food effect

CONTEXT AND OBJECTIVE

The objective of the study was to develop a stable capsule formulation of ziprasidone hydrochloride which can be administered without regards to food intake.

MATERIALS AND METHODS

The unstable anhydrous form of ziprasidone hydrochloride was stabilized employing hot-melt extrusion and further optimized by 3² central composite design. The formulation was optimized after establishing acceptable ranges for response variables like disintegration time, dissolution and impurity profile. A crossover fasted and fed in vivo study was conducted in human volunteers to assess the food-effect of optimized formulation vis-à-vis the marketed brand.

RESULTS AND DISCUSSION

The optimized formulation met in-house specifications for various response variables. Further, high values of correlation coefficient vouch the adequate selection of experimental design and its high prognostic ability. In our study, no significant difference was observed between the C_max and AUC values after administration of the optimized formulation in fasted and fed states. On the contrary, there was a statistically significant increase in the C_max and AUC values after oral administration of Zeldox in fed state in comparison to fasted state.

CONCLUSIONS

The present study describes the successful development of a stable formulation of 20 mg of ziprasidone devoid of any food-effects.