QbD-Enabled Development of Novel Stimuli-Responsive Gastroretentive Systems of Acyclovir for Improved Patient Compliance and Biopharmaceutical Performance

HSPiP and QbD Program-Based Analytical Method Development and Validation to Quantify Ketoconazole in Dermatokinetic Study

Ketoconazole (KTZ) is the most potential azole anti-mycotic drug. The quantification of KTZ from various layers of the skin after topical application of lipidic nanocarriers is critical. We addressed a sensitive, specific, simple, rapid, reproducible, and economic analytical method to quantify KTZ from the treated skin homogenate using the Hansen solubility parameter (HSP, HSPiP software)-based modeling and experimental design. The software provided various HSP values for KTZ and solvents to compose the mobile phase. The Taguchi model identified the significant sets of factors to develop a robust bioanalytical method with reduced variability. In the optimization, acetonitrile (ACN) concentration (X1 as A) and the pH of mobile phase (X2 as B) were two factors against two responses (Y1: peak area and Y2: retention time). The HPLC (high-performance liquid chromatography) method validation was carried out based on US-FDA guidelines for the developed KTZ formulations (suspension, solid nanoparticles, and commercial product) extracted from the treated rat skin. The experimental solubility of KTZ was found to be maximum in the two solvents (ACN and ethyl acetate), based on HSP values. Surface response methodology (SRM) identified remarkable impact of ACN concentration and the mobile phase pH on the peak area and retention time. Analytical limits (0.17 and 0.50 µg/mL) were established for KTZ-SLNs (extracted from the skin). The method was implemented with high reproducibility, accuracy, and selectivity to quantify KTZ from the treated rat skin.

QbD-Based Development of Cationic Self-nanoemulsifying Drug Delivery Systems of Paclitaxel with Improved Biopharmaceutical Attributes

The present studies describe quality-by-design-based design and characterization of cationic self-nanoemulsifying formulations of paclitaxel for improving its biopharmaceutical attributes. Solubility and phase titration experiments were designed to select the lipidic and emulsifying excipients. Two different types of lipidic nanoformulations were developed using medium-chain triglycerides (MCTs) and long-chain triglycerides (LCTs). The nanoformulations were optimized by mixture designs and subjected to evaluation for globule size, zeta potential, drug release, and intestinal permeability. Following apt mathematical modeling, the optimum nanoformulation was earmarked using numerical optimization. Further, cationic formulations were developed for both LCT- and MCT-containing formulations and subjected to performance evaluation. The optimized formulations were extensively evaluated, where an in vitro drug release study indicated 2.7-fold improvement in dissolution rate from optimized cationic nanoformulations over powder pure drug. Ex vivo and in situ evaluation performed on Wistar rats exhibited nearly six- to eightfold enhancement in permeation and absorption parameters of the drug for the optimized cationic nanoformulation as compared to the pure paclitaxel. Pharmacokinetic studies indicated nearly 13.4-fold improvement in AUC and C_max, along with 1.8-fold reduction in T_max of the drug from cationic nanoformulations as compared to the pure drug suspension. Moreover, nanoformulation containing long-chain lipids exhibited superior performance (1.18-fold improvement in drug absorption) over medium-chain lipids. Cytotoxicity evaluation of cationic nanoformulations on MCF-7 cells revealed significant reduction in growth vis-à-vis the pure drug. Overall, the current paper reports successful systematic development of paclitaxel-loaded cationic self-nanoemulsifying systems with distinctly improved biopharmaceutical performance.

Improving the biopharmaceutical attributes of mangiferin using vitamin E-TPGS co-loaded self-assembled phosholipidic nano-mixed micellar systems

The current research work encompasses the development, characterization, and evaluation of self-assembled phospholipidic nano-mixed miceller system (SPNMS) of a poorly soluble BCS Class IV xanthone bioactive, mangiferin (Mgf) functionalized with co-delivery of vitamin E TPGS. Systematic optimization using I-optimal design yielded self-assembled phospholipidic nano-micelles with a particle size of < 60 nm and > 80% of drug release in 15 min. The cytotoxicity and cellular uptake studies performed using MCF-7 and MDA-MB-231 cell lines demonstrated greater kill and faster cellular uptake. The ex vivo intestinal permeability revealed higher lymphatic uptake, while in situ perfusion and in vivo pharmacokinetic studies indicated nearly 6.6- and 3.0-folds augmentation in permeability and bioavailability of Mgf. In a nutshell, vitamin E functionalized SPNMS of Mgf improved the biopharmaceutical performance of Mgf in rats for enhanced anticancer potency.

Gastroretentive Cosolvent-Based In Situ Gel as a Promising Approach for Simultaneous Extended Delivery and Enhanced Bioavailability of Mitiglinide Calcium

Ion cross-linking in situ gels are novel liquid sustained-release drug delivery systems. These systems are unsuitable for poorly water-soluble drugs such as the novel antidiabetic drug mitiglinide calcium (MTG). Thus, our goal was to assess the possibility of using cosolvency approach in formulating gastroretentive in situ gel of the short half-life MTG to simultaneously enhance its bioavailability and sustain its release. MTG in situ gel formulations were developed using propylene glycol as a cosolvent to dissolve MTG in the polymer solution, followed by characterization of viscosity, gel strength, floating ability, and in vitro MTG release and phramacokinetics evaluation. The optimized formulation (composition: 1% gellan gum, 0.75% sodium alginate, 0.75% calcium carbonate, and 7.5% propylene glycol) exhibited reasonable viscosity but on introduction into simulated gastric fluid, it formed firm gel that floated within seconds over the surface and remained buoyant for 24 h. The formula exhibited in vivo sustained release manner of MTG over 24 h and improved the bioavailability of the drug. Thus, cosolvency presents a promising approach to deliver hydrophobic drugs in sustained-release liquid formulations. These formulations will improve diabetic patients' compliance by eliminating the necessity of frequent dosing with a better disease management.

Risk Assessment Integrated QbD Approach for Development of Optimized Bicontinuous Mucoadhesive Limicubes for Oral Delivery of Rosuvastatin

Statins are widely prescribed for hyperlipidemia, cancer, and Alzheimer's disease but are facing some inherent challenges such as low solubility and drug loading, higher hepatic metabolism, as well as instability at gastric pH. So, relatively higher circulating dose, required for exerting the therapeutic benefits, leads to dose-mediated severe toxicity. Furthermore, due to low biocompatibility, high toxicity, and other regulatory caveats such as product conformity, reproducibility, and stability of conventional formulations as well as preferentially higher bioabsorption of lipids in their favorable cuboidal geometry, enhancement in in vivo biopharmaceutical performance of Rosuvastatin could be well manifested in Quality by Design (QbD) integrated cuboidal-shaped mucoadhesive microcrystalline delivery systems (Limicubes). Here, quality-target-product-profile (QTPPs), critical quality attributes (CQAs), Ishikawa fishbone diagram, and integration of risk management through risk assessment matrix for failure mode and effects analysis (FMEA) followed by processing of Plackett-Burman design matrix using different statistical test for the first time established an approach to substantiate the claims that controlling levels of only these three screened out independent process variables, i.e., Monoolein (B = 800-1100 μL), Poloxamer (C = 150-200 mg), and stirring speed (F = 700-1000 rpm) were statistically significant to modulate and improve the biopharmaceutical performance affecting key attributes, viz., average particle size (Y₁ = 1.40-2.70 μ), entrapment efficiency (Y₂ = 62.60-88.80%), and drug loading (Y₃ = 0.817-1.15%), in QbD-enabled process. The optimal performance of developed Limicubes exhibited an average particle size of 1.8 ± 0.2 μ, entrapment efficiency 80.32 ± 2.88%, and drug loading 0.93 ± 0.08% at the level of 1100 μL (+ 1), 200 mg (+ 1), and 700 rpm (- 1) for Monoolein, Poloxamer, and stirring speed, respectively.

Dual stimuli-responsive Fe3O4 graft poly(acrylic acid)-block-poly(2-methacryloyloxyethyl ferrocenecarboxylate) copolymer micromicelles: surface RAFT synthesis, self-assembly and drug release applications

BACKGROUND

Stimuli-responsive polymer materials are a new kind of intelligent materials based on the concept of bionics, which exhibits more significant changes in physicochemical properties upon triggered by tiny environment stimuli, hence providing a good carrier platform for antitumor drug delivery.

RESULTS

Dual stimuli-responsive Fe3O4 graft poly(acrylic acid)-block-poly(2-methacryloyloxyethyl ferrocenecarboxylate) block copolymers (Fe3O4-g-PAA-b-PMAEFC) were engineered and synthesized through a two-step sequential reversible addition-fragmentation chain transfer polymerization route. The characterization was performed by FTIR, 1H NMR, SEC, XRD and TGA techniques. The self-assembly behavior in aqueous solution upon triggered by pH, magnetic and redox stimuli was investigated via zeta potentials, vibration sample magnetometer, cyclic voltammetry, fluorescent spectrometry, dynamic light scattering, XPS, TEM and SEM measurements. The experimental results indicated that the Fe3O4-g-PAA-b-PMAEFC copolymer materials could spontaneously assemble into hybrid magnetic copolymer micromicelles with core-shell structure, and exhibited superparamagnetism, redox and pH stimuli-responsive features. The hybrid copolymer micromicelles were stable and nontoxic, and could entrap hydrophobic anticancer drug, which was in turn swiftly and effectively delivered from the drug-loaded micromicelles at special microenvironments such as acidic pH and high reactive oxygen species.

CONCLUSION

This class of stimuli-responsive copolymer materials is expected to find wide applications in medical science and biology, etc., especially in drug delivery system.

QbD-Oriented Development and Characterization of Effervescent Floating-Bioadhesive Tablets of Cefuroxime Axetil

The objective of the present studies was systematic development of floating-bioadhesive gastroretentive tablets of cefuroxime axetil employing rational blend of hydrophilic polymers for attaining controlled release drug delivery. As per the QbD-based approach, the patient-centric target product profile and quality attributes of tablet were earmarked, and preliminary studies were conducted for screening the suitability of type of polymers, polymer ratio, granulation technique, and granulation time for formulation of tablets. A face-centered cubic design (FCCD) was employed for optimization of the critical material attributes, i.e., concentration of release controlling polymers, PEO 303 and HPMC K100 LV CR, and evaluating in vitro buoyancy, drug release, and ex vivo mucoadhesion strength. The optimized formulation was embarked upon through numerical optimization, which yield excellent floatation characteristic with drug release control (i.e., T 60% > 6 h) and bioadhesion strength. Drug-excipient compatibility studies through FTIR and P-XRD revealed the absence of any interaction between the drug and polymers. In vivo evaluation of the gastroretentive characteristics through X-ray imaging and in vivo pharmacokinetic studies in rabbits revealed significant extension in the rate of drug absorption (i.e., T max, K a, and MRT) from the optimized tablet formulation as compared to the marketed formulation. Successful establishment of various levels of in vitro/in vivo correlations (IVIVC) substantiated high degree of prognostic ability of in vitro dissolution conditions in predicting the in vivo performance. In a nutshell, the studies demonstrate successful development of the once-a-day gastroretentive formulations of cefuroxime axetil with controlled drug release profile and improved compliance.