Quality by Design (Qbd) in Analytical Method Development: A Systematic Review of Principles, Tools and Regulatory Perspectives

Analytical Quality by Design (AQbD) represent a structured, science and risk-based frame work for the analytical method development in the pharmaceutical industry. This systematic review evaluates the principles, statistical tools, regulatory expectations, and lifecycle management strategies associated with AQbD. A structured literature search was conducted using an electronic database including PubMed, Scopus, and Google Scholar for publications between 2008 and 2025. The review highlights key elements such as Analytical Target Profile (ATP), Critical Quality Attributes (CQAs), Critical Method Parameters (CMPs), risk assessment tools, Design of Experiments (DoE), and Method Operable Design Region (MODR). Regulatory alignment with the ICH guidelines (Q-series) Q8, Q9, Q10, Q14, and Q2(R2) is critically discussed. The findings indicate that the AQbD improves robustness, reduces variability, and enhances regulatory flexibility. Despite implementation challenges, AQbD is emerging as an regulatory expectation in modern pharmaceutical analysis.