Analytical method development in pharmaceutical sciences: A comprehensive review of contemporary frameworks, lifecycle approaches, and regulatory considerations

Analytical method development constitutes a foundational pillar of pharmaceutical quality assurance, underpinning the generation of reliable data for drug substance and drug product characterization, release testing, and stability evaluation. This review examines the current state of analytical method development within the pharmaceutical, biotechnology, and medical device industries, with particular emphasis on the evolving regulatory landscape shaped by the International Council for Harmonisation (ICH) guidelines Q2(R2) and Q14. The article explores the traditional one-factor-at-a-time (OFAT) approach to method development and contrasts it with the enhanced, systematic methodology promoted under the Analytical Quality by Design (AQbD) framework. Key elements of the enhanced approach are discussed, including the Analytical Target Profile (ATP), risk assessment strategies, design of experiments (DoE), and the establishment of a Method Operable Design Region (MODR). The lifecycle management concept, encompassing method design, performance qualification, and continued performance verification, is explored as a unifying paradigm that connects development activities to routine use and post-approval changes. Challenges to widespread AQbD adoption, including resource constraints, knowledge gaps, and the absence of mandated regulatory requirements, are critically evaluated. The article concludes by examining future directions, including the integration of artificial intelligence, machine learning, and process analytical technology into method development workflows, and offers practical recommendations for organizations seeking to transition from traditional to enhanced development strategies.