The influence of HPMC concentration on release of theophylline or hydrocortisone from extended release mini-tablets

Apixaban and clopidogrel in a fixed-dose combination: Formulation and in vitro evaluation

Fixed-dose combination (FDC) products represent a novel, safe, and cost-effective formulation. Combined use of anticoagulant and antiplatelet medications is common among comorbid cardiovascular patients. This study aimed to formulate FDC tablets for Apixaban and Clopidogrel, as prophylaxis and treatment of thrombo-embolic events. FDC tablets were developed by combining small tablets of Immediate-Release Clopidogrel 75 mg and Extend-Release Apixaban 5 mg through direct compression and wet granulation. Particularly, Apixaban tablets were developed using design expert software, and various types and concentrations of polymers were entered. For Clopidogrel tablets, various diluents were used to develop the formulation. Then, the dissolution profile for each formula was studied. Finally, the optimized formulations were encapsulated within hard gelatin capsules. Apixaban formulation followed zero-order with super case Ⅱ transport mechanism as the dominant mechanism of drug release. The Apixaban drug release rate was affected by the type and concentration of the polymers in the formulation (P < 0.05). As the HPMC concentration was increased, Apixaban release was retarded. For, Clopidogrel, the formulated tablets with spray-dried lactose filler and sodium stearyl fumarate lubricant were found to be stable with good properties. In conclusion, the optimum formulation yielded Clopidogrel and extended-release Apixaban for 24 h with the desired in vitro drug dissolution.

Current State of Minitablet Product Design: A Review

Interest in minitablets (MTs) has grown exponentially over the last 20 years and especially the last decade, as evidenced by the number of publications cited in Scopus and PubMed. MTs offer significant opportunities for personalized medicine, dose titration and flexible dosing, taste masking, and customizing drug delivery systems. Advances in specialized MT tooling, manufacturing, and characterization instrumentation have overcome many of the earlier development issues. Breakthrough MT swallowability, acceptability, and palatability research have challenged the long-standing idea that only liquids are acceptable dosage forms for infants and young children. MTs have been shown to be a highly acceptable dosage form for infants, small children, and geriatric patients who have difficulty swallowing. This review discusses the current state of MT applications, acceptability in pediatric and geriatric populations, medication adherence, manufacturing processes such as tableting and coating, running powder and tablet characterization, packaging and MT dispensing, and regulatory considerations.

Development of a Novel Vaginal Drug Delivery System to Control Time of Farrowing and Allow Supervision of Piglet Delivery

The swine industry has evolved significantly in the recent decades, but this has come at considerable expense to piglet survival. Breeding sows for greater prolificacy has been accompanied by a greater proportion of piglets being born underweight, of lower vigor, and higher susceptibility to early mortality. Inducing sows to farrow during working hours has the potential to increase piglet survivability, but non-therapeutic injectable products are often discouraged on farms. We aimed to design and develop a novel vaginal drug delivery system (NVDDS) that could reliably trigger luteolysis and induce parturition. To achieve this, two vaginal tablets containing the luteolytic agent cloprostenol were formulated to be inserted together: one would release constituents immediately on insertion (immediate release; IR) and the other would release cloprostenol in a controlled manner (controlled release; CR). The two formulations (IR and CR) were evaluated for drug release, swelling and bio-adhesion in conditions simulating the sow vaginal environment. The IR tablet released the drug completely for 5 min whereas the CR tablet took 5 h to release 50% of the drug. Furthermore, the release kinetics were evaluated by fitting the dissolution profiles into different mathematical models. Both IR and CR tablets were best fitted by the Makoid–Banakar model which assumes release by summation of different mechanisms. The performance of the optimized formulations was studied in vivo with 161 Large White x Landrace sows of varying parity (0–5). The sows were assigned to five groups. Group 1 (SI) received a single vulval injection of cloprostenol at 0700 h (n = 32), group 2 (SDI) received the same dose split in two parts, at 0700h and 1300h (n = 33). Group 3 (IRT) animals were administered an IR tablet at 0700h (n = 32), while group 4 (IRCRT) received both IR and CR tablets at 0700 h (n = 33). Group 5 was untreated and served as a control (n = 32). The interval to farrowing was longer (p < 0.001) for controls than for treated sows, but there were no differences among cloprostenol treatments for timing of farrowing. The finding confirms the efficacy of the NVDDS for induction of farrowing in sows.

Formulation development and in-vitro/ex-vivo evaluation for a polysaccharide-based colon targeted matrix tablet

OBJECTIVE

The objective of this study was to develop and optimize a microflora-triggered colon targeted sustained-release dosage form using gum ghatti (GG) and hydroxypropyl methylcellulose (HPMC K100).

METHODS

GG and HPMC K100 were used to prepare microflora triggered colon targeted sustained-release dosage form. For evaluation, two different tablets comprising metoprolol succinate and mesalamine as an active ingredient were used with the objective of developing a platform technology for various categories of drugs. The tablets were coated with Eudragit® L100 and Eudragit® S100 to provide enteric coating and evaluated for hardness, thickness, friability, weight variation, disintegration, and drug content. In vitro release studies for the prepared tablets were carried out mimicking the physiological transit time. Further, the effects of microflora were evaluated using rat cecal content.

RESULTS

The in vitro dissolution profile of coated matrix tablets showed that 86.03±0.43% of metoprolol succinate and 80.26±0.67% of mesalamine were released at the end of 12 h. The ex vivo dissolution profile of coated matrix tablets showed that 96.50±0.27% of metoprolol succinate and 92.58±0.39% of mesalamine were released at the end of 12 h in the presence of rat ceacal content. The developed formulation was stable when subjected to the standard ICH stability study conditions.

CONCLUSION

The result of this study showed that gum ghatti together with hydroxypropyl methylcellulose could be successfully used for the preparation of microflora triggered colon targeted matrix tablets.

Mini-Tablets versus Nanoparticles for Controlling the Release of Amoxicillin: In vitro/In vivo Study

Introduction

Controlling the drug release from the dosage form at a definite rate is the main challenge for a successful oral controlled-release drug delivery system. In this study, mini-tablets (MTs) and lipid/polymer nanoparticles (LPNs) of lipid polymer and chitosan in different ratios were designed to encapsulate and control the release time of Amoxicillin (AMX).

Methods

Physical characteristics and in vitro release profiles of both MT and LPN formulations were studied. Antimicrobial activity and oral pharmacokinetics of the optimum MT and LPN formulations in comparison to market tablet were studied in rats.

Results

All designed formulations of AMX as MTs and LPNs showed accepted characteristics. MT-6 (Compritol/Chitosan 1:1) showed the greatest retardation among all prepared minitablet preparations, releasing about 79.5% of AMX over 8 h. In contrast, LPN-11 (AMX: Cr 1:3/Chitosan 1 mg/mL) had the slowest drug release, revealing the sustained release of 80.9% within 8 h. The MIC of both optimized tablet formula (MT-6) and LPNs formula (LPN-11) was around two-fold lower than the control against H. pylori. The C_max of MT-6 and LPN11 were non significantly different compared with the marketed AMX product. While the bioavailability experiment proved that the relative bioavailability of the AMX was 1.85 and 1.8 after the oral use of LPN11 and MT-6, respectively, compared to the market tablet.

Conclusion

The results verified that both controlled-release mini-tablets and lipid/polymer nanoparticles can be used for sustaining the release and hence improve the bioavailability of amoxicillin.

A Raman imaging-based technique to assess HPMC substituent contents and their effects on the drug release of commercial extended-release tablets

In this study, we tried to assess the substitute contents of HPMC used in commercial extended-release tablets directly by an innovative Raman imaging-based analysis technique and find their effects on the in vitro performance of these pharmaceuticals. Twenty-seven batches of metformin hydrochloride extended-release tablets from various sources were collected in the Chinese mainland market. While Raman imaging was used to qualitatively analyze the composition of the tablets, the MeO and HPO contents of HPMC were quantitatively assessed by a newly proposed calculation method based on the Raman intensity of corresponding characteristic band. Additionally, the dissolution test was performed to evaluate the relationship between HPMC substitution pattern and in vitro behavior. In sum, our findings indicate that the drug release rate can be downregulated by increasing the MeO content of HPMC, while the high HPO content would largely eliminate the variation of drug release profiles among batches.

A Critical Review of Analytical Methods in Pharmaceutical Matrices for Determination of Corticosteroids

Corticosteroids are a class of hormones released by the adrenal cortex, which includes glucocorticoids and mineralocorticoids. Glucocorticoids have an important role in the metabolism of carbohydrates, proteins and calcium and effective anti-inflammatory and immunosuppressive activity. Due to their intense immunomodulatory and anti-inflammatory activity, glucocorticoids are used in the treatment of various inflammatory, malignant, allergic conditions such as rhinitis, asthma, dermatological, rheumatic, ophthalmic and neurological diseases, as well as after organ transplants. They are the most widely prescribed drugs in the world. The objective of this review is to provide an overview of the analytical methods in pharmaceutical matrices for determination of corticosteroids. In this study, the predominance of liquid chromatography methods for the analysis of corticosteroids from pharmaceutical products is evident for both liquid and semisolid dosage forms as well as for solids. The same can be said for topical, oral and parenteral formulations. Methods such as spectrophotometry are also used, but given the advantages of chromatographic methods such as better selectivity and sensitivity, they have become the choice for analysis of these drugs, however, most methods still do not meet the credentials of "green chemistry."

Glibenclamide Mini-tablets with an Enhanced Pharmacokinetic and Pharmacodynamic Performance

In an attempt to decrease the dose, anticipated side effects, and the cost of production of glibenclamide, GLC, a potent oral hypoglycemic drug, the enhancement of the dissolution and hence the oral bioavailability were investigated. Adsorption and co-adsorption techniques using carriers having a very large surface area and surface active agents were utilized to enhance the drug dissolution. Moreover, the Langmuir adsorption isotherms were constructed to identify the type and mechanism of adsorption. The optimized formulation showing the highest in vitro release was compressed into mini-tablet to facilitate drug administration to elderly patients and those having swallowing difficulties. The produced mini-tablets were tested for their mechanical strength and in vitro release pattern. In addition, the pharmacodynamic and pharmacokinetic studies in New Zealand rabbits were performed using the optimized mini-tablet formulation. Mini-tablets containing GLC co-adsorbate with Pluronic F-68 and Laponite RD showed 100 ± 1.88% of GLC released after 20 min. Pharmacodynamic studies in rabbits revealed significantly higher (p ≤ 0.05) hypoglycemic effect with the optimized mini-tablets at a lower GLC dose compared to mini-tablets containing the commercial GLC dose. Moreover, pharmacokinetic analysis showed significantly higher (p ≤ 0.05) AUC, C_max, and shorter T_max. The optimized mini-tablet formulation showed 1.5-fold enhancement of the oral bioavailability compared to mini-tablets containing untreated GLC. It could be concluded that the co-adsorption technique successfully enhanced the oral bioavailability of GLC. Furthermore, the produced mini-tablets have a higher oral bioavailability with a lower GLC dose, which could offer economic benefit for industry as well as acceptability for patients.

Sustained-release formulation of sarpogrelate hydrochloride

Sarpogrelate HCl (SGL) has been used clinically as an anti-platelet drug for the prevention of thrombus, proliferation of vascular smooth muscle cells and platelet aggregation. This study was to investigate the bioavailability of sustained-release solid dispersion (SR-SD) formulation of SGL to sustain the drug release for up to 24 h. The SR-SD formulations with various drug-to-polymer ratios were prepared by hot-melt coating method. Waxy material carriers such as Compritol 888 ATO and stearyl alcohol were added to SGL and different amounts of HPMC K 15 (HPMC) were mixed. Dissolution profile and bioavailability were compared to SGL powder. Compritol 888 ATO showed the controlling effect of the initial release rate of drug from the formulation and the controlling effect was increased for 24 h by addition of HPMC. As the amount of HPMC increased, the drug release rate from SR-SD decreased because HPMC formed gel layer in aqueous media. Pharmacokinetic study showed that the AUC and Tmax of SGL in SR-SD formulation increased as compared to the SGL powder. These data suggest that the SR-SD formulation effectively controls the drug release rate for 24 h, hoping to be useful for the development of once-a-day formulation of SGL.

The effect of HPMC particle size on the drug release rate and the percolation threshold in extended-release mini-tablets

The particle size of HPMC is a critical factor that can influence drug release rate from hydrophilic matrix systems. Percolation theory is a statistical tool which is used to study the disorder of particles in a lattice of a sample. The percolation threshold is the point at which a component is dominant in a cluster resulting in significant changes in drug release rates. Mini-tablets are compact dosage forms of 1.5-4 mm diameter, which have potential benefits in the delivery of drug to some patient groups such as pediatrics. In this study, the effect of HPMC particle size on hydrocortisone release and its associated percolation threshold for mini-tablets and tablets was assessed. For both mini-tablets and tablets, large polymer particles reduced tensile strength, but increased the drug release rate and the percolation threshold. Upon hydration, compacts with 45-125 μm HPMC particles formed a strong gel layer with low porosity, reducing hydrocortisone release rates. In comparison, faster drug release rates were obtained when 125-355 µm HPMC particles were used, due to the greater pore sizes that resulted in the formation of a weaker gel. Using 125-355 µm HPMC particles increased the percolation threshold for tablets and to a greater extent for mini-tablets. This work has demonstrated the importance of HPMC particle size in ER matrices, the effects of which are even more obvious for mini-tablets.