Supplementary file 1_Regulatory implementation of Optical Coherence Tomography as an analytical technique in pharmaceutical fillings.docx

Optical Coherence Tomography (OCT) has emerged as a powerful non-destructive imaging tool capable of delivering high-resolution cross-sectional images of drug formulations, particularly useful for evaluating coating uniformity, detecting defects and characterizing multi-layered structures in solid dosage forms. Despite OCT potential, its widespread acceptance has been limited due to the lack of pharmacopeial monographs and specific regulatory guidelines. In recent years, growing regulatory interest in advanced analytics has prompted increased attention to method validation, alignment with Quality by Design (QbD) principles and compliance with Good Manufacturing Practices (GMP). This work provides an integrated perspective on the development, implementation and regulatory evaluation of OCT in the pharmaceutical industry. It reviews the implementation process and the evolving regulatory framework surrounding OCT in pharmaceutical applications, along with practical considerations for its adoption. As interest in OCT on the part of regulatory bodies grows, the pharmaceutical industry is moving toward broader engagement, emphasizing the need for standardization and eventual inclusion of OCT methodologies in regulatory frameworks. With continued collaboration between the industry stakeholders, regulatory agencies and standard-setting organizations, OCT is positioned to become an integral component of modern pharmaceutical quality control strategies.