Azilsartan-d5 is primarily used in research and development within the pharmaceutical industry. It serves as a stable isotope-labeled internal standard in analytical studies, particularly in mass spectrometry. This compound aids in the accurate quantification and detection of azilsartan in biological samples, such as blood or plasma, during pharmacokinetic and metabolism studies. Its use ensures precision and reliability in measuring drug concentrations, which is critical for understanding drug behavior, efficacy, and safety in clinical trials. Additionally, it supports the development of robust analytical methods for quality control in drug manufacturing processes.