RHENIUM-188 HAS FAVORABLE PHYSICAL PROPERTIES AS A THERA- PEUTIC RADIONUCLIDE, T-1/2 OF 17.

RHENIUM-188 HAS FAVORABLE PHYSICAL PROPERTIES AS A THERA- PEUTIC RADIONUCLIDE, T-1/2 OF 17.0 HOURS, EMAX BETA 2.2 MEV,AND EGAMMA 155 KEV. METHODOLOGY HAS BEEN DEVELOPED FOR CONJUGATION OF RHENIUM IN STABLE COMPLEXED FORM TO ANTIBODIES. THE OBJECTIVE OF THIS PROPOSAL IS TO DEVELOP THE TECHNOLOGY NECESSARY TO MAKE HIGH SPECIFIC ACTIVITY RE- 188 AVAILABLE FOR RADIOIMMUNOTHERAPY USING THE W-188/RE-188 GENERATOR SYSTEM. THIS WILL BE DONE BY APPLYING TECHNOLOGY USED FOR MO-99/TC-99MM GENERATORS THAT EMPLOYS LOW SPECIFIC ACTIVITY MO-99 AND A GEL COLUMN BASED ON THE METAL OXIDE. TUNGSTEN-188 WILL BE PREPARED AT LOW AND HIGH ACTIVITY LEVELS, AND VARIOUS ELUTION PARAMETERS THAT AFFECT YIELD, RADIONUCLIDIC, AND CHEMICAL PURITY WILL BE STUDIED, AS WELL AS LIFETIME OF USE OF THE RADIONUCLIDE GENERATOR. THIS PHASE I STUDY IS EXPECTED TO RESULT IN A GENERATOR DESIGN THAT WILL ALLOW PRODUCTION OF RE-188 FOR ANIMAL AND CLINICALEVALUATION IN RADIOLABELED ANTIBODY FORM FOR FUTURE PHASE IISTUDIES. A SUCCESSFUL COMBINATION OF GENERATOR TECHNOLOGY, ANTIBODY RADIOLABELING METHODOLOGY, AND ANTIBODIES THAT TARGET TUMORS EFFECTIVELY WOULD RESULT IN A CONVENIENT SYSTEM FOR CANCER TREATMENT. THE LONG HALF-LIFE OF THE W-188 PRECURSOR (69.4 DAYS) WOULD FACILITATE COMMERCIAL SUPPLY OF THE GENERATORS.