Gradient RP-HPLC method for the determination of potential impurities in atazanavir sulfate

Determination and quantification of related substances and degradation products in bictegravir by full factorial design evaluated HPLC and mass spectrometry

Determining and quantifying novel impurities and degraded impurities of a drug product is always a continuous challenge to enhancing the drug quality for patients' safety. Herein, our work deals with (i) developing a rapid, accurate, and reliable high-performance liquid chromatographic validation method to quantify the bictegravir drug (integrase inhibitors of antiretroviral drugs) and its novel related impurities at low levels, and (ii) the liquid chromatography-mass spectrometry (LC-MS) method to identify degraded impurities. Separation of bictegravir acid (impurity-I) and methyl bictegravir (impurity-II) impurities which are identified by LC-MS in the bictegravir drug was executed by developing a method and the same method performance evaluated by using full factorial design. This developed analytical technique gave a well-separated peak of bictegravir and related analytes such as bictegravir acid (impurity-I) and methyl bictegravir (impurity-II), adequate with the peak properties as per USP guidelines. The method's sensitivity and linearity are demonstrated by its detection and quantification limits at low levels with a correlation coefficient of 0.998. The method's repeatability, specificity, and accuracy suggest that this developed technique is a reliable determination strategy for the bictegravir drug substance and its related impurities (impurity-I and impurity-II) in a simple, feasible, and affordable way.

Quality by design (QbD)-based fabrication of atazanavir-loaded nanostructured lipid carriers for lymph targeting: bioavailability enhancement using chylomicron flow block model and toxicity studies

Atazanavir (ATV) is widely used as anti-HIV agent having poor aqueous solubility needs to modulate novel drug delivery system to enhance therapeutic efficiency and safety. The main objective of the present work was to fabricate ATV-loaded nanostructured lipid carriers (NLCs) employing quality by design (QbD) approach to address the challenges of bioavailability and their safety after oral administration. Herein, the main objective was to identify the influencing variables for the production of quality products. Considering this objective, quality target product profile (QTPP) was assigned and a systematic risk assessment study was performed to identify the critical material attributes (CMAs) and critical process parameter (CPP) having an influence on critical quality attributes (CQAs). Lipid concentrations, surfactant concentrations, and pressure of high-pressure homogenizer were identified as CMAs and CPP. ATV-NLCs were prepared by emulsification-high pressure homogenization method and further lyophilized to obtain solid-state NLCs. The effect of formulation variables (CMAs and CPP) on responses like particle size (Y₁), polydispersity index (Y₂), and zeta potential (Y₃) was observed by central composite rotatable design (CCRD). The data were statistically evaluated by ANOVA for confirmation of a significant level (p < 0.05). The optimal conditions of NLCs were obtained by generating design space and desirability value. The lyophilized ATV-NLCs were characterized by DSC, powder X-ray diffraction, and FT-IR analysis. The morphology of NLCs was revealed by TEM and FESEM. In vitro study suggested a sustained release pattern of drug (92.37 ± 1.03%) with a mechanism of Korsmeyer-Peppas model (r² = 0.925, and n = 0.63). In vivo evaluation in Wistar rats showed significantly higher (p < 0.001) plasma drug concentration of ATV-NLCs as compared to ATV-suspension using chylomicron flow block model. The relative bioavailability of ATV-NLCs was obtained to be 2.54 folds. Thus, a safe and promising drug targeting system was successfully developed to improve bioavailability and avoiding first-pass effect ensures to circumvent the acute-toxicity of liver.

Development and validation of a UPLC-MS method for determination of atazanavir sulfate by the "analytical quality by design" approach

A UPLC-MS method for the estimation of atazanavir sulfate was developed using the "analytical quality by design" approach. The critical chromatographic quality attributes identified were retention time, theoretical plates and peak tailing. The critical method parameters established were percent of organic modifier, flow rate and injection volume. Optimization performed using Box-Behnken Design (BBD) established 10 % organic modifier, 0.4 mL min-1 flow rate and 6-µL injection volume as the optimum method conditions. Atazanavir sulfate eluted at 5.19 min without any interference. Method validation followed international guidelines. The method has proven linearity in the range of 10-90 µg mL-1. Recovery was between 100.2-101.0 % and precision within the accepted limits (RSD 0.2-0.7 %). LOD and LOQ were 2.68 and 8.14 µg mL-1, resp. Stress testing stability studies showed atazanavir sulfate to degrade under acidic and basic conditions. The suggested technique is simple, rapid and sustainable. It is, therefore, suggested for routine analysis of atazanavir sulfate.

S, Talluri MVNK. Study of forced degradation behaviour of cobicistat and atazanavir using LC/ESI/QTOF/MS; a combination of in-sourced and collision-induced dissociation for evaluation of the fragmentation patterns of degradation products

The present study describes the LC/MS/MS characterization of degradation products of cobicistat and atazanavir.