Development of an Innovative Quality by Design (QbD) Based Stability-Indicating HPLC Method and its Validation for Clofazimine from its Bulk and Pharmaceutical Dosage Forms

Development of a novel quality by design-enabled stability-indicating HPLC method and its validation for the quantification of nirmatrelvir in bulk and pharmaceutical dosage forms

A systematic and novel quality by design-enabled, rapid, simple, and economic stability-indicating HPLC method for quantifying nirmatrelvir (NMT) was successfully developed and validated. An analytical target profile (ATP) was established, and critical analytical attributes (CAAs) were allocated to meet the ATP requirements. The method used chromatographic separation using a Purosphere column with a 4.6 mm inner diameter × 250 mm (2.5 μm). The analysis occurred at 50°C with a flow rate of 1.2 mL/min and detection at 220 nm. A 10 μL sample was injected, and the mobile phase consisted of two components: mobile phase A, containing 0.1% formic acid in water (20%), and mobile phase B, containing 0.1% formic acid in acetonitrile (80%). The diluent was prepared by mixing acetonitrile and water at a 90:10 v/v ratio. The retention time for the analyte was determined to be 2.78 min. Accuracy exceeded 99%, and the correlation coefficient was greater than 0.999. The validated HPLC method was characterized as precise, accurate, and robust. Significantly, NMT was found to be susceptible to alkaline, acidic, and peroxide conditions during forced degradation testing. The stability-indicating method developed effectively separated the degradation products formed during stress testing, underlining its effectiveness in stability testing and offering accuracy, reliability, and sensitivity in determining NMT.

A brief review on application of design of experiment for the analysis of pharmaceuticals using HPLC

The quality pioneer Dr. Joseph M. Juran first proposed the idea of quality by design. According to him, pharmaceutical quality by design is an organised approach to product development that starts with predetermined goals and places an emphasis on product, process understanding, control based on reliable science and quality risk management. The quality of a product or process can typically be affected by a number of input elements. Design of experiments has been employed widely recently to understand the impacts of multidimensional and interactions of input parameters on the output responses of analytical procedures and pharmaceutical goods. Depending on the design of experiments objectives, screening, characterization, or optimization of the process and formulation, a variety of designs, such as factorial or mixture, can be used. The most popular designs used in the stage of screening or factor selection are the 2-Level Factorial and Plackett-Burman designs, both of which have two levels for each factor (k), both economical and effective, and in optimization widely used designs in this step are full factorial at three levels, central composite, Box-Behnken design. The analysis of variance, regression significance, and lack of fit of the regression model were some of the key topics covered in the discussion of the main components of multiple regression model adjustment. Design of experiments is thus the primary element of the formulation and analytical quality by design. The details about design of experiments used for the analysis of pharmaceutical formulation using HPLC.

Implementation of Quality by Design Approaches for Development and Validation of Reverse-Phase High-Performance Liquid Chromatography Assay Method for Determination of Glycyrrhizin in Nanoformulation

Glycyrrhizin (GL) is the principal constituent of Glycyrrhiza glabra, having antiallergic, anticancer, anti-inflammatory, and antimicrobial action. The reverse-phase high-performance liquid chromatography (RP-HPLC) analytical method was used to quantitatively estimate GL in a nanoformulation and validated as per International Conference on Harmonization Q2 (R1) standards. A stationary phase of the C18-HL reversed-phase column and a mobile phase of acetonitrile and water were used for effective elution. The chromatographic conditions of RP-HPLC were optimized utilizing a quality-by-design approach to accomplish the required chromatographic separation of GL from its nanoformulation with minimal experimental runs. Optimized RP-HPLC conditions for the assay method consist of acetonitrile (41%) and water, pH 1.8, balanced with phosphoric acid (0.1%) as a mobile phase with a flow rate of 1 mL/min. The retention time was found at 7.25 min, and method validation confirmed its sensitivity, preciseness, accuracy, and robustness.

Drilling into "Quality by Design" Approach for Analytical Methods

The need for consistency in analytical method development reinforces the dependence of pharmaceutical product development and manufacturing on robust analytical data. The Analytical Quality by Design (AQbD), akin to the product Quality by Design (QbD) endows a high degree of confidence to the method quality developed. AQbD involves the definition of the analytical target profile as starting point, followed by the identification of critical method variables and critical analytical attributes, supported on risk assessment and design of experiment tools for the establishment of a method operable design region and control strategy of the method. This systematic approach moves away from reactive troubleshooting to proactive failure reduction. The objective of this review is to highlight the elements of the AQbD framework and provide an overview of their implementation status in various analytical methods used in the pharmaceutical field. These methodologies include but are not limited to, high-performance liquid chromatography, UV-Vis spectrophotometry, capillary electrophoresis, supercritical fluid chromatography, and high-performance thin-layer chromatography. Finally, a critical appraisal is provided to highlight how regulators have encouraged AQbD principles application to boost the prevention of method failures and a better understanding of the method operable design region (MODR) and control strategy, ultimately resulting in cost-effectiveness and regulatory flexibility.

Analytical Quality-by-Design-Based Systematic Optimization of RP-HPLC Method Conditions to Analyze Simultaneously Chloroquine Phosphate and Flavopiridol in Stress-Induced Combined Drug Solution and Pharmaceutical Emulsions

A design of experiments (DoE)-driven RP-HPLC method conditions was employed to analyze simultaneously chloroquine (CQ) phosphate and flavopiridol (FLAP) in emulsions and solution. After subjecting the various critical method attributes to preliminary risk assessment and screening by Pareto-chart-based fractional factorial design, the 17 runs were produced in Box-Behnken design for optimization. Analysis of variance, lack of fit, prediction equations, 3D response surface plots and contour plots were used to evaluate the critical analytical attributes such as retention time, tailing factor and theoretical plate count. The optimized RP-HPLC method conditions include 262 nm as detection wavelength, 37°C temperature for column, 20-μl injection volume, 1-ml/min flow rate and mobile phase mixture [70:30 ratio of 0.4% triethylamine in methanol&sodium phosphate buffer (11 mM, pH 3.0)]. The studied validation parameters were found within the ICH-prescribed limits. Exposing the combined drug solution at oxidative stress condition resulted to diminish the FLAP recovery value (53.39 ± 0.86) and arrival of an extra chromatographic peak. However, the % drug entrapment efficiency values of 96.22 ± 2.47 and 85.86 ± 3.66, respectively, were noticed for CQ phosphate and FLAP in emulsions. Thus, DoE-driven approach could be helpful for systematically optimizing RP-HPLC method conditions.

An effective and stability-indicating method development and optimization utilizing the Box-Behnken design for the simultaneous determination of acetaminophen, caffeine, and aspirin in tablet formulation

Analytical techniques must be sensitive, specific, and accurate to assess the active pharmaceutical ingredients in pharmaceutical dosage forms. The quality-by-design (QbD) application has proven to be a practical method for magnifying HPLC operations. This article discusses the successfully developed QbD-based stability-indicative LC method for evaluating acetaminophen, caffeine, and aspirin (ASP) in tablet dosage form. To achieve the necessary chromatographic separation, Milli-Q water, methanol, and glacial acetic acid were employed in the following ratios: 63:35:2 (v/v/v) for mobile phase A and 18:80:2 (v/v/v) for mobile phase B. The flow rate, column temperature, and detecting wavelength were 1.0 ml/min, 40°C, and 275 nm, respectively, and an InertSustain C18 analytical column (150 × 4.6 mm, 3 μm) was used. Linearity was between 10.0 and 150.0 μg/ml for ASP and acetaminophen and between 2.6 and 39.0 μg/ml for caffeine. The accuracy findings were more than 97%, and the correlation coefficient for all three components was found to be greater than 0.999. The validated HPLC method yielded reliable and accurate results. ASP was shown to be vulnerable to both acid and alkaline hydrolysis in the forced degradation study. The described method is capable of separating the degradants produced during stress testing and is regarded as stability indicating. The proposed method can be used for a wider range of other formulations with an appropriate diluent selection and sample preparation procedure optimization.

Quality by Design Approach for a Multicomponent Quantification Using HPLC-PDA and HPLC-MS: Application to Dosage Form and Biological Body Fluids

A multicomponent pharmaceutical that contains loratadine, paracetamol, and pseudoephedrine was quantified using HPLC-PDA. The three analytes were well-separated and quantified in the dosage form on a C-18 column using a gradient mobile phase. A quality by design strategy was followed to achieve the challenging separation. Screening and optimization steps were carried out to investigate the effect of many factors on the studied responses with a minimum number of runs. The ANOVA of the factorial model showed that % acetonitrile (factor A), flow rate (factor B), and pH (factor C) were significant. The detection of the analytes’ peaks was carried out using a PDA detector at 248nm for loratadine and paracetamol, and 214 nm for pseudoephedrine. The second method was SPE-HPLC-MS, where the three analytes and desloratadine, the active metabolite of loratadine, were quantified in spiked plasma and urine, using betamethasone valerate as an internal standard. The recovery of the analytes from body fluids was above 96%, and the LOQ was below 0.5 ng/mL. The validation of the developed HPLC-PDA method was achieved as per ICH guidelines, whereas the HPLC-MS method was validated according to FDA guidelines for bioanalytical method validation. The results were compared with the reported method, and no significant differences were found.

Interleukin-13 overexpressing mice represent an advanced pre-clinical model for detecting the distribution of anti-mycobacterial drugs within centrally necrotizing granulomas

The Mycobacterium tuberculosis-harboring granuloma with a necrotic center surrounded by a fibrous capsule is the hallmark of tuberculosis (TB). For a successful treatment, antibiotics need to penetrate these complex structures to reach their bacterial targets. Hence, animal models reflecting the pulmonary pathology of TB patients are of particular importance to improve the preclinical validation of novel drug candidates. M. tuberculosis-infected interleukin-13-overexpressing (IL-13^tg) mice develop a TB pathology very similar to patients and, in contrast to other mouse models, also share pathogenetic mechanisms. Accordingly, IL-13^tg animals represent an ideal model for analyzing the penetration of novel anti-TB drugs into various compartments of necrotic granulomas by matrix-assisted laser desorption/ionization–mass spectrometry imaging (MALDI-MS imaging). In the present study, we evaluated the suitability of BALB/c IL-13^tg mice for determining the antibiotic distribution within necrotizing lesions. To this end, we established a workflow based on the inactivation of M. tuberculosis by gamma irradiation while preserving lung tissue integrity and drug distribution, which is essential for correlating drug penetration with lesion pathology. MALDI-MS imaging analysis of clofazimine, pyrazinamide, and rifampicin revealed a drug-specific distribution within different lesion types, including cellular granulomas, developing in BALB/c wild-type mice, and necrotic granulomas in BALB/c IL-13^tg animals, emphasizing the necessity of preclinical models reflecting human pathology. Most importantly, our study demonstrates that BALB/c IL-13^tg mice recapitulate the penetration of antibiotics into human lesions. Therefore, our workflow in combination with the IL-13^tg mouse model provides an improved and accelerated evaluation of novel anti-TB drugs and new regimens in the preclinical stage.

DoE-based validation of a HPLC-UV method for quantification of rotigotine nanocrystals: Application to in vitro dissolution and ex vivo nasal permeation studies

The current work is focused on optimization, development, and validation of a sensitive and specific reversed-phase high-performance liquid chromatography (RP-HPLC) method for the estimation of rotigotine (RTG) in bulk and nanoformulations. The RP-HPLC method was effectively optimized using the concepts of design of experiments. Critical method variables (CMVs) were screened using Plackett-Burman design. Box-Behnken, a surface response methodology-based design, was further used for the optimization of CMVs with the number of theoretical plates and retention time (min) as responses. The optimized chromatographic conditions for the RP-HPLC method were: acetonitrile proportion: 54% v/v, pH of buffer: 5.0 (10 mM), and flow rate: 0.65 mL/min. The number of theoretical plates and retention time in the study were found to be 11206 and 7.65 min, respectively. The developed method exhibited good linearity (R² = 0.9995) within a range of 25-600 ng/mL and LOD and LOQ were found to be 9 and 12 ng/mL, respectively. The developed RP-HPLC method was found sensitive, accurate, precise, specific, robust, and stability indicating according to the regulatory guidelines. The validated method was efficiently applied for in vitro dissolution study, ex vivo nasal permeation study, and estimation of drug content of RTG nanocrystals.

Application of Design of Experiments® Approach-Driven Artificial Intelligence and Machine Learning for Systematic Optimization of Reverse Phase High Performance Liquid Chromatography Method to Analyze Simultaneously Two Drugs (Cyclosporin A and Etodolac) in Solution, Human Plasma, Nanocapsules, and Emulsions

The objectives of current investigation are (1) to find out wavelength of maximum absorbance (λ_max) for combined cyclosporin A and etodolac solution followed by selection of mobile phase suitable for the RP-HPLC method, (2) to define analytical target profile and critical analytical attributes (CAAs) for the analytical quality by design, (3) to screen critical method parameters with the help of full factorial design followed by optimization with face-centered central composite design (CCD) approach-driven artificial neural network (ANN)-linked with the Levenberg-Marquardt (LM) algorithm for finding the RP-HPLC conditions, (4) to perform validation of analytical procedures (trueness, linearity, precision, robustness, specificity and sensitivity) using combined drug solution, and (5) to determine drug entrapment efficiency value in dual drug-loaded nanocapsules/emulsions, percentage recovery value in human plasma spiked with two drugs and solution state stability analysis at different stress conditions for substantiating the double-stage systematically optimized RP-HPLC method conditions. Through isobestic point and scouting step, 205 nm and ACN:H₂O mixture (74:26) were selected respectively as the λ_max and mobile phase. The ANN topology (3:10:4) indicating the input, hidden and output layers were generated by taking the 20 trials produced from the face-centered CCD model. The ANN-linked LM model produced minimal differences between predicted and observed values of output parameters (or CAAs), low mean squared error and higher correlation coefficient values in comparison to the respective values produced by face-centered CCD model. The optimized RP-HPLC method could be applied to analyze two drugs concurrently in different formulations, human plasma and solution state stability checking.

Nanostructured lipid carrier-mediated lung targeted drug delivery system to enhance the safety and bioavailability of clofazimine

Tuberculosis (TB) disease is caused due to the infection of Mycobacterium tuberculosis bacilli which reside in alveolar macrophages (AMs). Clofazimine (CLF) has been reinstated clinically for the treatment of TB. However, major challenge of using CLF is its severe side-effects after oral administration. The present research was aimed to establish the safety and enhance the bioavailability of CLF by loading it into nanostructured lipid carriers (CLF-NLCs) and mannosylated NLCs (M-CLF-NLCs) to selectively target the drug toward AMs. The safety of CLF-NLCs and M-CLF-NLCs was evaluated by in vitro hemocompatibility studies, cell viability studies on macrophage J774 cell lines, and in vivo acute inhalation toxicity studies. The bioavailability was estimated by single-dose pharmacokinetics and biodistribution studies. Hemocompatibility studies showed normal RBCs count and least hemolysis of 0.23 ± 0.081% for M-CLF-NLCs treated group. Cell viability studies revealed greater safety of NLCs than CLF-drug dispersion in the concentration range of 2.5-25 μg/ml. In vivo acute toxicity studies revealed no physiological or behavioral changes and no mortality recorded over 14 days period. In pharmacokinetic studies, a maximum concentration of the drug (C_max) of 35.44 ± 0.34 μg/g from M-CLF-NLCs after 48 h and longer residence time in lung tissues observed due to its sustained release and mannose receptor-mediated endocytosis. M-CLF-NLCs showed a maximum AUC_0-∞ value of 2691.83 h μg/ml in lungs that indicated twofold greater bioavailability as compared to CLF-drug dispersion. Thus, mannosylated NLCs can be used as promising carriers for the safe and effective delivery of CLF via inhalation route for the management of TB disease.