Radiopharmaceuticals are the main tool in nuclear medicine for diagnosis and therapy of human diseases, which are totally depending on these important agents. Development of new radiopharmaceuticals is based on the clever design of not only the carrier molecules guiding the drug to the target cells/organs but also majorly based on the physicochemical properties of the radionuclides. Beta and recently alpha emitters have become the major source of therapeutic energetic particles for developing therapeutic radiopharmaceuticals in the last three decades. However availability, cost, stability of complexes as well as metallic/non-metallic properties of these radioisotopes play a major role in the field. On the other hand, development of new chelating agents with high affinity for various metallic radionuclides as well as room temperature labeling has emerged new series of therapeutic and/or diagnostic radiopharmaceuticals known as theranostics. The other major issue in this field is the agreement of physical half-life with the biological half-life to allow adequate targeting time and reducing the unwanted radiation dose and unspecific organ targeting.
With the advent of biotechnological advances and knowledge of molecular and cellular biology, radioimmunotherapy (RIT) has become a highly promising oncologic therapeutic modality with established clinically efficacy, particularly in non-Hodgkin’s lymphomas. A brief review of the published literature on the clinical applications of radioimmunotherapy, is provided.
In the other hands a series of radiolabeled peptides have been designed and optimized for tumor-targeted peptide receptor radionuclide therapy (PRRNT). Pre-clinical and clinical applications of PRRT have shown promising results on tumor response, overall survival, and quality of life in patients with several kinds of tumors. 90Y-DOTA-TOC and 177Lu-DOTA-TATE are two of the most common radiopharmaceuticals with symptomatic improvements and complete clinical data. Several strategies have been designed to improve the therapeutic efficacy of PRRT. For instance, radiolabeled peptides could be optimized by the amino acid modification and radionuclide selection. Healthy tissue protective agents and multi-cycle procedures could effectively decrease the side effects of PRRNT. Furthermore, combination treatments, including PRRT combined with surgery, chemotherapeutic agents, or radiosensitizing agents could be applied to increase the effectiveness of PRRT.
Other important issues such as legal aspects and focusing on new/alternate production/application methods for critical radionuclides is also another important task being pursued in the section. IAEA activities in the field is majorly based on the demands received from the Member States and is organized in a way to cover all regional parts of the globe.