Design, Optimization, and Correlation of In Vitro/In Vivo Disintegration of Novel Fast Orally Disintegrating Tablet of High Dose Metformin Hydrochloride Using Moisture Activated Dry Granulation Process and Quality by Design Approach

Advances in metformin-delivery systems for diabetes and obesity management

Metformin is a medication that is commonly prescribed to manage type 2 diabetes. It has been used for more than 60 years and is highly effective in lowering blood glucose levels. Recent studies indicate that metformin may have additional medical benefits beyond treating diabetes, revealing its potential therapeutic uses. Oral medication is commonly used to administer metformin because of its convenience and cost-effectiveness. However, there are challenges in optimizing its effectiveness. Gastrointestinal side effects and limitations in bioavailability have led to the underutilization of metformin. Innovative drug-delivery systems such as fast-dissolving tablets, micro/nanoparticle formulations, hydrogel and microneedles have been explored to optimize metformin therapy. These strategies enhance metformin dosage, targeting, bioavailability and stability, and provide personalized treatment options for improved glucose homeostasis, antiobesity and metabolic health benefits. Developing new delivery systems for metformin shows potential for improving therapeutic outcomes, broadening its applications beyond diabetes management and addressing unmet medical needs in various clinical settings. However, it is important to improve drug-delivery systems, addressing issues such as complexity, cost, biocompatibility, stability during storage and transportation, loading capacity, required technologies and biomaterials, targeting precision and regulatory approval. Addressing these limitations is crucial for effective, safe and accessible drug delivery in clinical practice. In this review, recent advances in the development and application of metformin-delivery systems for diabetes and obesity are discussed.

Development of Losartan Orally Disintegrating Tablets by Direct Compression: a Cost-Effective Approach to Improve Paediatric Patient's Compliance

The development of suitable dosage forms is essential for an effective pharmacological treatment in children. Orally disintegrating tablets (ODTs) are attractive dosage forms that avoid swallowing problems, ensure dosage accuracy and are easy to administer as they disintegrate in the oral cavity. This study aimed to develop ODTs containing losartan potassium (LP) for the treatment of arterial hypertension in children. The ODTs, produced by the cost-effective manufacturing process of direct compression, consisted of a mixture of diluent, superdisintegrant, glidant and lubricant. Five superdisintegrants (croscarmellose sodium, two grades of crospovidone, sodium starch glycolate and pregelatinized starch) were tested (at two concentrations), and combined with three diluents (mannitol, lactose and sorbitol). Thus, thirty formulations were evaluated based on disintegration time, hardness and friability. Two formulations, exhibiting the best results concerning disintegration time (< 30 s), hardness and friability (≤ 1.0%), were selected as the most promising ones for further evaluation. These ODTs presented favourable drug-excipient compatibility, tabletability and flow properties. The in vitro dissolution studies demonstrated 'very rapid' drug release. Preliminary stability studies highlighted the requirement of a protective packaging. All quality properties retained appropriate results after 12 months of storage in airtight containers. In conclusion, the ODTs were successfully developed and characterised, suggesting a potential means to accomplish a final prototype that enables an improvement in childhood arterial hypertension treatment.

Application of Response Surface Methodology to Improve the Tableting Properties of Poorly Compactable and High-Drug-Loading Canagliflozin Using Nano-Sized Colloidal Silica

Designing a robust direct compression (DC) formulation for an active pharmaceutical ingredient (API) with poor flow and compaction properties at a high API load is challenging. This study tackled two challenges: the unfavorable flow characteristics and tableting problems associated with a high-drug-loading canagliflozin (CNG), facilitating high-speed DC tableting. This was accomplished through a single-step dry coating process using hydrophilic nano-sized colloidal silica. A 32 full-factorial experimental design was carried out to optimize the independent process variables, namely, the weight percent of silica nanoparticles (X1) and mixing time (X2). Flow, bulk density, and compaction properties of CNG-silica blends were investigated, and the optimized blend was subsequently compressed into tablets using the DC technique. A regression analysis exhibited a significant (p ≤ 0.05) influence of both X1 and X2 on the characteristics of CNG with a predominant effect of X1. Additionally, robust tablets were produced from the processed powders in comparison with those from the control batch. Furthermore, the produced tablets showed significantly lower tablet ejection forces than those from the control batch, highlighting the lubrication impact of the silica nanoparticles. Interestingly, these tablets displayed improved disintegration time and dissolution rates. In conclusion, a dry coating process using silica nanoparticles presents a chance to address the poor flow and tableting problems of CNG, while minimizing the need for excessive excipients, which is crucial for the effective development of a small-sized tablet and the achievement of a cost-effective manufacturing process.

Development and Optimization of Sildenafil Orodispersible Mini-Tablets (ODMTs) for Treatment of Pediatric Pulmonary Hypertension Using Response Surface Methodology

The availability of age-appropriate oral dosage forms for pediatric patients has remained a challenge. Orodispersible mini-tablets (ODMTs) are a promising delivery system for pediatric patients. The purpose of this work was the development and optimization of sildenafil ODMTs as a new dosage form for the treatment of pulmonary hypertension in children using a design-of-experiment (DoE) approach. A two-factor, three levels (32) full-factorial design was employed to obtain the optimized formulation. The levels of microcrystalline cellulose (MCC; 10–40% w/w) and partially pre-gelatinized starch (PPGS; 2–10% w/w) were set as independent formulation variables. In addition, mechanical strength, disintegration time (DT), and percent drug release were set as critical quality attributes (CQAs) of sildenafil ODMTs. Further, formulation variables were optimized using the desirability function. ANOVA analysis proved that MCC and PPGS had a significant (p < 0.05) impact on CQAs of sildenafil ODMTs with a pronounced influence of PPGS. The optimized formulation was achieved at low (10% w/w) and high (10% w/w) levels of MCC and PPGS, respectively. The optimized sildenafil ODMTs showed crushing strength of 4.72 ± 0.34 KP, friability of 0.71 ± 0.04%, DT of 39.11 ± 1.03 s, and sildenafil release of 86.21 ± 2.41% after 30 min that achieves the USP acceptance criteria for ODMTs. Validation experiments have shown that the acceptable prediction error (<5%) indicated the robustness of the generated design. In conclusion, sildenafil ODMTs have been developed as a suitable oral formulation for the treatment of pediatric pulmonary hypertension using the fluid bed granulation process and the DoE approach.

Study of Orally Disintegrating Tablets Using Erythritol as an Excipient Produced by Moisture-Activated Dry Granulation (MADG)

Moisture-activated dry granulation (MADG) is an eco-friendly granulation method that uses a small amount of water and insoluble excipients to absorb moisture. MADG is expected to improve productivity and reduce costs. Erythritol, an excipient used for preparing orally disintegrating tablets (ODTs), has poor tabletability and is difficult to form into tablets by conventional methods, such as high-shear granulation (HSG) and direct compression. In this study, we optimized the manufacturing conditions for ODTs to improve the tabletability of erythritol using MADG. The disintegration time of tablets made using the MADG method was approximately one-tenth that of those made using the HSG method, and the hardness was approximately 1.4 times higher. Moreover, MADG could delay disintegration and improve tabletability. We further attempted to optimize the manufacturing conditions using MADG, particularly in terms of the amount of water used. The disintegration time increased as the amount of added water increased. Moreover, water absorption tests revealed that capillary wetting decreased as the amount of water added increased, but the initial wetting did not change. These results suggested that the disintegration time was prolonged because of the increase in granule density and decrease in capillary wetting with the increase in the amount of added water. The hardness of the tablets increased because of the easy deformation of the granules after the addition of up to 3% water; however, when more than 3% water was added, the hardness decreased because of the aggregation of the granules with the excess water. Finally, two-dimensional maps of the effect of the amount of added water and water activity indicated that tablets with a hardness of ≥80 N and a disintegration time of ≤15 s could be produced by adjusting the amount of added water to within the range of 2.2–3.3% and water activity to 0.3–0.53. These results indicate that MADG can improve the tabletability of erythritol and be used for the granulation of ODTs. Tablets with appropriate hardness and disintegration properties can be produced by adjusting the water content to approximately 2.7% and the water activity to approximately 0.4 when producing ODTs with MADG.

Design Space Approach for the Optimization of Green Fluidized Bed Granulation Process in the Granulation of a Poorly Water-Soluble Fenofibrate Using Design of Experiment

In the pharmaceutical industry, the systematic optimization of process variables using a quality-by-design (QbD) approach is highly precise, economic and ensures product quality. The current research presents the implementation of a design-of-experiment (DoE) driven QbD approach for the optimization of key process variables of the green fluidized bed granulation (GFBG) process. A 3² full-factorial design was performed to explore the effect of water amount (X₁; 1–6% w/w) and spray rate (X₂; 2–8 g/min) as key process variables on critical quality attributes (CQAs) of granules and tablets. Regression analysis have demonstrated that changing the levels of X₁ and X₂ significantly affect (p ≤ 0.05) the CQAs of granules and tablets. Particularly, X₁ was found to have the pronounced effect on the CQAs. The GFBG process was optimized, and a design space (DS) was built using numerical optimization. It was found that X₁ and X₂ at high (5.69% w/w) and low (2 g/min) levels, respectively, demonstrated the optimum operating conditions. By optimizing X₁ and X₂, GFBG could enhance the disintegration and dissolution of tablets containing a poorly water-soluble drug. The prediction error values of dependent responses were less than 5% that confirm validity, robustness and accuracy of the generated DS in optimization of GFBG.

Development and Evaluation of Cannabidiol Orodispersible Tablets Using a 23-Factorial Design

Orodispersible tablets (ODTs) are pharmaceutical formulations used to obtain fast therapeutic effects, usually recommended for geriatric and pediatric patients due to their improved compliance, bioavailability, ease of administration, and good palatability. This study aimed to develop ODTs with cannabidiol (CBD) phytocannabinoid extracted from Cannabis sativa used in the treatment of Lennox–Gastaut and Dravet syndromes. The tablets were obtained using an eccentric tableting machine and 9 mm punches. To develop CBD ODTs, the following parameters were varied: the Poloxamer 407 concentration (0 and 10%), the type of co-processed excipient (Prosolv^® ODT G2—PODTG2 and Prosolv^® EasyTab sp—PETsp), and the type of superdisintegrant (Croscarmellose—CCS, and Soy Polysaccharides—Emcosoy^®—EMCS), resulting in eleven formulations (O1–O11). The following dependent parameters were evaluated: friability, disintegration time, crushing strength, and the CBD dissolution at 1, 3, 5, 10, 15, and 30 min. The dependent parameters were verified according to European Pharmacopoeia (Ph. Eur.) requirements. All the tablets obtained were in accordance with quality requirements in terms of friability (less than 1%), and disintegration time (less than 180 s). The crushing strength was between 19 N and 80 N. Regarding the dissolution test, only four formulations exhibited an amount of CBD released higher than 80% at 30 min. Taking into consideration the results obtained and using the Modde 13.1 software, an optimal formulation was developed (O12), which respected the quality criteria chosen (friability 0.23%, crushing strength of 37 N, a disintegration time of 27 s, and the target amount of CBD released in 30 min of 99.3 ± 6%).

An Industrial Procedure for Pharmacodynamic Improvement of Metformin HCl via Granulation with Its Paracellular Pathway Enhancer Using Factorial Experimental Design

Background

Sorbitan monostearate is a surfactant used in the food industry. It was proved as a penetration enhancer to metformin HCl via a paracellular pathway. It is solid at room temperature and has a low melting point. Therefore, it was selected, as a granulating agent for metformin HCl.

Methods

Multi-level factorial design was applied to determine the optimized formula for industrial processing. The selected formulations were scanned using an electron microscope. Differential scanning calorimetry was used to ascertain the crystalline state of a drug. A modified non-everted sac technique, suggested by the authors, was used to evaluate the in vitro permeation enhancement of the drug. To simulate the emulsification effect of the bile salt, a tween 80 was added to the perfusion solution. As a pharmacodynamic marker, blood glucose levels were measured in diabetic rats.

Results

The results showed that drug permeability increases in the presence of tween 80. Drug permeability from granules increased than that of the pure drug or pure drug with tween 80. The prepared granules decreased blood glucose levels of diabetic rats than the pure drug and drug plus tween 80. There was an excellent correlation between the results of the drug permeation percent in vitro and the dropping of blood glucose level percent in vivo.

Conclusion

Improving the drug permeation and consequently, the drug pharmacodynamic effect in addition to an excellent micromeritics property of the prepared drug granules showed the dual enhancement effect of the suggested industrial procedure. Therefore, we suggest the same industrial procedure for other class III drugs.

Formulation, Optimization and In Vitro Evaluation of Fast Disintegrating Tablets of Salbutamol Sulphate using a Combination of Superdisintegrant and Subliming Agent

AIM

The present research work was aimed to formulate fast disintegrating tablets (FDTs) of salbutamol sulphate (SBS) using a combination of superdisintegrant and subliming agent, optimize the formulation and evaluate the in vitro performance of the developed FDTs.

MATERIALS AND METHODS

A formulation of SBS FDT was developed using a combination of superdisintegrant - crospovidone and subliming agent - ammonium bicarbonate (AB) in which formulation variables, namely levels of crospovidone and microcrystalline cellulose (MCC):Mannitol (MNTL) ratio were evaluated for their effects on the response variables - disintegration time, hardness, friability and wetting time of the resulting FDTs. By employing a central composite design (CCD) methodology, the FDTs were optimized to achieve optimum levels of the formulation factors.

RESULTS

The desired optimum condition was obtained at 7.82% crospovidone and 70% of 1.56:1 MCC: MNTL ratio while maintaining AB at 5% level for aesthetic reasons. Under the optimized conditions, the disintegration time, hardness, friability and wetting time were 14.57±0.53 sec, 7.17±0.82 kg/cm2, 0.311% and 13.14±0.69 sec, respectively. The experimentally observed responses were found to be in close agreement with the predicted values for the optimized formulation. Moreover, the validity of the obtained optimal point was confirmed by the low magnitude of percent prediction error (<5%).

CONCLUSION

FDTs of SBS were successfully formulated and optimized using CCD employing a combination of superdisintegrant and subliming agents.

Exploitation of Design-of-Experiment Approach for Design and Optimization of Fast-Disintegrating Tablets for Sublingual Delivery of Sildenafil Citrate with Enhanced Bioavailability Using Fluid-Bed Granulation Technique

Sildenafil citrate undergoes first-pass metabolism, resulting in poor oral bioavailability at 25-41% of the administered dose. This study aimed to design and optimize fast-disintegrating tablets for the sublingual delivery of sildenafil citrate to improve bioavailability and facilitate rapid onset of action. The design-of-experiment (DoE) approach using 32 full factorial design was conducted to develop a new formulation of sildenafil fast-disintegrating sublingual tablets (FDSTs) using the fluid-bed granulation technique. The levels of partially pre-gelatinized starch (5-15%) and microcrystalline cellulose (10-60%) were selected as independent formulation variables. The prepared FDSTs were investigated for physical properties. Further, the optimum formulation was chosen for in vivo study in rabbits. Regression analysis showed that independent variables have a significant (p < 0.05) influence on critical attributes of FDSTs. The optimized formulation showed acceptable mechanical strength (friability < 1.0%) with very fast disintegration (14.561 ± 0.84 s) and dissolution (94.734 ± 2.76% after 15 min). Further, the optimized formulation demonstrated a significant increase (p < 0.01) in Cmax and AUC0-∞ with short tmax compared to the market product (Viagra®). Based on these results, using the DoE approach, a high level of assurance was achieved for FDSTs' product quality and performance.

Enhancing the Low Oral Bioavailability of Sulpiride via Fast Orally Disintegrating Tablets: Formulation, Optimization and In Vivo Characterization

Sulpiride (SUL) is a dopamine D₂-receptor antagonist used for management of GIT disturbance and it has anti-psychotic activities based on the administered dose. SUL undergoes P-glycoprotein efflux, which lead to poor bioavailability and erratic absorption. Therefore, the objective of this research was an attempt to enhance the oral bioavailability of SUL via formulation of fast disintegrating tablets (SUL-FDTs) with a rapid onset of action. A 3² full-factorial design was performed for optimization of SUL-FDTs using desirability function. The concentration of superdisintegrant (X₁) and Prosolv^® (X₂) were selected as independent formulation variables for the preparation and optimization of SUL-FDTs using direct compression technique. The prepared SUL-FDTs were investigated regarding their mechanical strength, disintegration time, drug release and in vivo pharmacokinetic analysis in rabbits. The optimized formulation has hardness of 4.58 ± 0.52 KP, friability of 0.73 ± 0.158%, disintegration time of 37.5 ± 1.87 s and drug release of 100.51 ± 1.34% after 30 min. In addition, the optimized SUL-FDTs showed a significant (p < 0.01) increase in C_max and AUC(_0-∞) and a relative bioavailability of about 9.3 fold compared to the commercial product. It could be concluded that SUL-FDTs are a promising formulation for enhancing the oral bioavailability of SUL concomitant with a fast action.