Current Pharmaceutical Analysis - Online First

Developing a simple HPLC method requires an expansive array of literary evidence and experimental routines to perceive the nature of a drug and eventually determine the specific mobile phase and column to be used for attaining better results.

The study aimed to develop and optimize a new, simplified, robust, and sensitive method for the determination of cilostazol in tablets by high-performance liquid chromatography using a Box Behnken design.

The chromatographic separation was carried out on an ODS C18 (4.6 X 250mm and 5µm) column with acetonitrile and methanol (25:75% v/v) at an effluent flow rate of 1 mL/min and detected at 257 nm.

The method was found to be linear in the concentration range of 10-50 µg/mL, and the correlation coefficient was found to be 0.988, and the recovery of cilostazol was 98.16%. The optimized method validated as per ICH Q2A guidelines was found to be accurate, precise, robust, and stable.

This research thus throws light on the implementation of statistical multivariate analysis techniques used for drug analysis.

Pirtobrutinib is a novel non-covalent BTK inhibitor used to treat adult patients with relapsed/refractory mantle cell lymphoma and B-cell leukemias. The mechanism of action involves binding and inhibition of Bruton's tyrosine kinase (BTK).

The main goal of the current work was to create a selective liquid chromatographic method (RP-HPLC) that is easy to use, accurate and exact for quantifying Pirtobrutinib and its degradation products, thereby seeking insight into the drug’s degradation behaviour.

Using an isocratic mode and a 50:50 mixture of acetonitrile and buffer solution (0.1% orthophosphoric acid) as the mobile phase, a High Performance Liquid Chromatographic System with a PDA detector and an X-Bridge Phenyl column (150 x 4.6mm, 3.5µm) at a flow rate of 1.0 ml/min was able to achieve good chromatographic separation. At 219 nm, the detection was carried out. A retention time of 2.271 minutes was discovered. To ascertain the drug's degrading properties and stability, forced degradation tests were carried out, leading to the development of the RPHPLC method. The chemical structures of the degradation products were clarified and their fragmentation mechanisms were suggested using LC-MS.

The suggested approach demonstrated a linearity within the 25-150% (2.5 to 15μg/mL) concentration range, with a correlation coefficient of 0.9999. The precision of the system (measured by % RSD=0.49) and the method (measured by % RSD=0.86) were all within the acceptable limits set by ICH guidelines, with % RSDs less than 1% and less than 2% for system precision and method precision, respectively. The LOD was 0.3μg/mL, and the LOQ was1μg/mL. Pirtobrutinib underwent rigorous tests for forced degradation under the specified conditions outlined in ICH Q1 (R2) guidelines. Pirtobrutinib was primarily broken down in acidic, alkaline, peroxide, and thermal conditions. It was found to remain stable under reduction, photolytic, and hydrolytic conditions. Through LC-MS analysis, the chemical structures of the resulting degradation by-products were identified, along with the proposed pathways of their fragmentation.

The current study gives insight into Pirtobrutinib’s degradation behaviour. Pirtobrutinib was stable in reduction, photolytic, and hydrolytic conditions but degraded more readily in acidic, alkaline, peroxide, and thermal environments. The degradation products were characterized as 4-carbamoyl-5-chloro-3(4-((5-fluoro-2-methoxybenzamido)methyl)phenyl)-4,5-dihydro-1H-pyrazol-5-aminium (acid impurity, DP1), N-(4-(4,5-diamino-1H-pyrazol-3-yl)benzyl)-5-fluoro-2-hydroxybenzamide (alkali impurity, DP2), 5-amino-3-(4-((s-fluro-2-methoxybenzamido)methyl))-4,5dihydro-1H-pyrazol-5-aminium (peroxide impurity, DP3) and N-(4-(4-acetyl-5-amino-4,5-dihydro-1H-pyrazol-3-yl)benzyl)-5-fluoro-2-methoxybenzamide compound with λ¹-oxidane (1:1) (thermal impurity, DP4) and their fragmentation pathways were proposed. This study presents the first ever reported method for the quantification of Pirtobrutinib. It ensures precise quantitation of Pirtobrutinib, a new Bruton's Tyrosine Kinase inhibitor, and its degradation products. The method's enhanced sensitivity and regulatory compliance ensure its consistent use in the quantification of Pirtobrutinib.

Rapid tablet or capsule dissolution requires the tablet to disintegrate and dissolve at a higher rate, enhancing drug dissolution and bioavailability. Suitable disintegrants have shown an appreciable rate of disintegration or dissolution. Using factorial design for formulation to improve bioavailability is a key focus in pharmaceutical research to enhance dissolution.

Azelnidipine (Azp) tablets were formulated with Hydroxypropyl β-cyclodextrin (HβCD), β-cyclodextrin (βCD), and Kolliphor HS15 (HS15) to enhance solubility. A 2³ factorial design optimized the formulation, focusing on disintegration time (DT) and time for 90% dissolution (T90). Eight formulations (F1-F8) were prepared using the kneading method. Tablets were evaluated for physical properties, drug content, friability, dissolution, and drug-excipient interactions (FTIR and DSC). The optimal formulation (F9) was determined via desirability analysis.

Tablets showed acceptable Carr's index (CI), Hausner ratio (HR), and Angle of Repose (AR). Increasing βCD concentration decreased DT, enhancing water absorption and faster dissolution. βCD tablets had the lowest DT among the formulations, with F4 showing the best disintegration. Higher HS15 concentration also reduced DT, with F8 achieving the highest drug release (T90%) within 60 minutes. R² values ranged from 0.922 to 0.994, indicating high predictability. The optimal formulation had a desirability of 1.0, consisting of 3.523 mg HS15, 28.4 mg βCD, and 1.49 mg βCD, with a DT of 102 ± 1.13 seconds and 98% dissolution. FTIR and DSC confirmed no drug–excipient interactions.

Optimized super disintegrant concentrations and wet granulation techniques resulted in tablets with strong mechanical properties, rapid disintegration, and consistent drug content. Future research and in vivo studies should explore additional excipient combinations.

Doxorubicin (DOX) causes lethal cardiotoxicity, which limits its clinical utility. The molecular mechanisms and effective strategies to combat its cardiotoxicity need further exploration. DT-010, a novel conjugate of danshensu (DSS) and tetramethylpyrazine(TMP), is considered a promising candidate for treating DOX-induced cardiotoxicity. In this study, we aimed to investigate the underlying molecular mechanisms of DOX-induced cardiotoxicity and the cardioprotective effects of DT-010.

Isobaric tags for relative and absolute quantitation (iTRAQ) in proteomics analysis was employed to analyze the differentially expressed proteins in DOX-injuried hearts. Gene ontology (GO) enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were carried out to evaluated the potential mechanisms of DOX-induced cardiotoxicity. The effects of NCAM1 on DOX-induced cardiotoxicity in H9c2 cells, as well as the cardioprotection of DT-010 were assessed through NACM1siRNA transfection, cell viability assay, cell apoptosis staining, reactive oxygen species measurement, and western blotting.

Proteomics analysis revealed that several signaling pathways, including the tricarboxylic acid (TCA) cycle and oxidative phosphorylation, were involved in DOX-induced cardiotoxicity. NCAM1 is one of the significantly changed proteins. DT-010 treatment regulated NCAM1 protein expression. Silencing NCAM1 in DOX-treated H9c2 cells decreased cell viability, increased cell apoptosis and reactive oxygen species (ROS) generation, and attenuated the cardioprotective effects of DT-010. Furthermore, NCAM1 knockdown promoted p38 activation and inhibited the expressions of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) and heme oxygenase-1 (HO-1) in DOX-treated cells.

These findings indicate a definite role of NCAM1 in DOX-induced cardiotoxicity and DT-010-exerted cardioprotection, which is mediated through the p38 and Sirt1/PGC-1α/HO-1 pathway.

The in-vitro release test (IVRT) is a tool to measure the amount and the release rate of active pharmaceutical compounds released from topical semisolid dosage forms. The IVRT provides significant information for product performance assessment and evaluation. It is also used to assess the bioequivalence study (biowaivers) for topical semisolid products.

The study aims to develop and validate the IVRT method for qualitative and quantitative estimation of ganciclovir topical products and to demonstrate the similarity between the marketed reference product and the in-house test product of ganciclovir ophthalmic gel.

The method was developed using a vertical diffusion cell with a synthetic cellulose membrane, simulated tear fluid as the receiver media, and UV detection. The IVRT study was performed at 100rpm and 32^oC for 6hr. The marketed formulation containing 0.15%w/w ganciclovir was used as a reference.

The in-house test product of ganciclovir met all characterization criteria. The analytical method was optimized and validated with a concentration range of 2-14μg/ml and a regression coefficient of 0.9997 as per the ICH guideline. The developed IVRT method was simple, economical, linear, robust, reproducible, sensitive, specific, and selective to evaluate the drug release from the formulation. The %recovery at 6hr was found to be 84.43% and 78.68% for reference and test product of ganciclovir ophthalmic gel with correlation coefficient R² 0.9947 and 0.9921, respectively, this value justified the biowaivers between the reference and test formulation.

This method can be utilized to check topical semisolid product quality, product performance, and product uniformity. Additionally, it can also be used to waive the requirement for bioequivalency studies for ganciclovir ophthalmic gel.

Aqueous solubility is a key parameter in understanding drug transport in the body and also in the development of analytical methods. Determination of a complete pH-solubility profile is essential during the pre-formulation stage, and it is also required to define the class of drug according to the biopharmaceutical classification system.

This study aimed to generate solubility data to obtain a complete pH-solubility profile for Atorvastatin calcium using the spectrophotometric method and to develop models for the prediction of aqueous solubility of Atorvastatin calcium at a given combination of the pH and temperature.

The developed pH independent spectrophotometric method was applied to determine the pH solubility profile of the drug at three different temperatures. Models for the prediction of solubility were generated by using a full factorial design and validated by determining solubility experimentally at some combinations of pH and temperature within the design spaces.

Solubility of Atorvastatin calcium was found to increase gradually with pH within a range of pH 1.2-4.0 and pH 9.0-12.0 while increasing drastically with pH within a range of pH 4.0-9.0 at all three temperatures. Experimental values of solubility of Atorvastatin calcium were found to be in good agreement with predicted values from models.

Predictive models generated from the experimental values are good indicative of the solubility of Atorvastatin calcium with respect to temperature and pH of the medium and can be used for accurate prediction of aqueous solubility within the design space of the models.