Therapy with 188Re-labeled radiopharmaceuticals: an overview of promising results from initial clinical trials.

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.