Abstract: Under the U.S. medical product regulatory framework, innovative medical devices used in conjunction with approved drugs for new usage will often raise regulatory issues. To address these regulatory challenges and foster industry innovation, the FDA has proposed a new regulatory pathway. This paper traces the regulatory journey and risk analysis of the FDA in approving new uses of optical imaging agents and contrast agents through the medical device regulatory pathway. On this basis, it discusses the FDA's efforts to expand this pathway to broader applications and analyzes the reasons behind its lack of success. Finally, it discusses the current regulatory status of similar products in China, suggesting that this regulatory pathway may have certain implications for the regulation of similar products in China.