An Overview of Structural Framework and Classification of Theranostic Radiopharmaceuticals

Abstract Radiopharmaceuticals constitute the backbone of nuclear medicine research and have been commonly used in diagnostic imaging and radionuclide therapy. In the past, there has been a strong emphasis on the meticulous design and development of radiotheranostics for targeted molecular imaging and therapy of different types of tumors. Theranostic radiopharmaceuticals offer synergistic advantages of simultaneous molecular imaging and radionuclide therapy all in one molecule. Owing to their successful pre‐clinical and clinical applications, many new theranostic radiopharmaceuticals have been explored in recent years. This review aims to provide a comprehensive overview of the design and the structural framework of theranostic radiopharmaceuticals. In this review, we have primarily focused on the different types of chelating agents, linkers, and radionuclides used for the development of potential radiotheranostics. In addition, this review also summarizes the classification and the different categories of theranostic radiopharmaceuticals such as molecular radiotheranostics and nano‐radiotheranostics along with their pre‐clinical and clinical theranostic applications. The recent developments and the theranostic applications of small molecule‐based radiotheranostics, antibody‐based radiotheranostics, peptide‐based radiotheranostics, and nanoparticle‐based radiotheranostics have also been reviewed for inspiring research efforts towards the development of efficient radiotheranostics.