Therapy with 188 Re-Labeled Radiopharmaceuticals: An Overview of Promising Results from Initial Clinical Trials

Abstract

The development of an in-house ¹⁸⁸W/¹⁸⁸Re-generator has greatly increased the use of ¹⁸⁸Re for treating various diseases. ¹⁸⁸Re is of widespread interest due to its attractive physical and chemical properties. Many new radiopharmaceuticals labeled with ¹⁸⁸Re have been developed and are currently in clinical trials, such as: ¹⁸⁸Re-labeled renal excreting agents like ¹⁸⁸Re-mercaptoacetylglycylglycylglycine (MAG₃) and ¹⁸⁸Re-diethylenetriamine pentaacetic acid (DTPA) for prevention of coronary arterial restenosis; ¹⁸⁸Re-labeled phosphonates such as ¹⁸⁸Re-hydroxyethylidene diphosphonate (HEDP), ¹⁸⁸Re-alendronate (ABP), and ¹⁸⁸Re-ethylenediamine-N,N,N′,N′-tetrakis(methylene phosphoric) acid (EDTMP) for palliation of metastatic bone pain; ¹⁸⁸Re-labeled lipiodol such as ¹⁸⁸Re-n-hexyldiaminedithiol (HDD)-lipiodol for treatment of liver cancer; and ¹⁸⁸Re-labeled colloids and microspheres for treatment of diseases such as rheumatoid arthritis, peritoneal effusion, and other solid tumors. However, there is still a need to develop new ¹⁸⁸Re-labeled radiopharmaceuticals that are more specific for target lesions such as cancer-specific monoclonal antibodies and peptides. The availability of ¹⁸⁸Re from a generator at a reasonable cost may help increase not only the research activities but also the clinical applications of ¹⁸⁸Re-labeled radiopharmaceuticals.