Application of analytical quality by design (AQbD) for stability-indicating method development for quantification of nevirapine and its degradation products

Abstract

Development of stability-indicating method by liquid chromatography are always a challenge for analytical researchers. A traditional way is by varying one chromatographic parameter at a time assessing the responses from each test. Recent international guidelines encourage the implementation of systematic approaches in analytical development, such as Analytical Quality by Design (AQbD). The aim of this paper was to develop, using the AQbD approach, an efficient and selective stability-indicating method by high performance liquid chromatography for nevirapine and its related substances. The Analytical Target Profile (ATP) and the Critical Method Attributes (CMA) were determined. Through the risk assessment studies, the high-risk analytical conditions were considered as Critical Method Parameters (CMP) and they were screened and optimized by Design of Experiment (DoE). The Method Operable Design Region (MODR) was defined using Monte Carlo Simulation. A control strategy was established by the definition of the system suitability of the analytical procedure. Optimal chromatographic conditions were achieved using an isocratic elution consisting of a mixture of 5 mM ammonium formate buffer pH 5.4/acetonitrile/methanol (60:20:20), with a flow rate of 1.0 mL/min, oven temperature of 30 °C, injection volume of 5 µL and an ACE C18 250 mm x 4,6 mm x 5 µm chromatographic column. Finally, analytical validation and forced degradation studies confirmed the performance of the analytical method. From the estimation of measurement uncertainty, strategies were outlined so that the method is fit for purpose throughout its life cycle. Additionally, guard bands were defined, changing the specification for nevirapine quantification from 90 % to 100 % to the acceptance zone of 92.1–107.9 %. The AQbD method development provided strong justifications for the selection of important parameters for nevirapine method during regulatory filling. Furthermore, with the pass/fail decision rule using guard band, restricted acceptance zones were defined, reducing the risk to the consumer of taking a drug product whose batch was inadequately approved.