What is a Common Technical Document (CTD)? CTD serves as a standardized submission format for the regulatory approval of pharmaceutical and biologic products. This structured document is represented by the CTD triangle, illustrating its organization into three main modules: Quality (Module 3), Safety (Module 4), and Efficacy (Module 5). These modules systematically present information on product quality, safety, and efficacy. Additionally, two supporting modules, Administrative and Prescribing Information (Module 1) and Nonclinical Overview (Module 2), contribute to the comprehensive data submitted to regulatory authorities. The CTD triangle provides a systematic framework for presenting data, facilitating the evaluation of a product's safety, efficacy, and quality throughout its development and registration process.