Production, Quality Control and Pharmacokinetic Studies of 166Ho-EDTMP for Therapeutic Applications

Abstract

(166)Ho-EDTMP is a major therapeutic agent which is widely used in bone palliation therapy. In this study, a (166)Ho-EDTMP complex was prepared successfully using an in-house synthesized EDTMP ligand and (166)HoCl(3). Ho-166 chloride was obtained by thermal neutron irradiation (1 Ã 10(13) ncm(â2)s(â1)) of natural Ho(NO(3))(3) samples (specific activity = 3â5 GBq/mg), dissolved in acidic media. The radiochemical purity of (166)Ho-EDTMP was checked by ITLC (>99%) and stability studies in presence of human serum and final preparation were performed. The biodistribution of (166)Ho-EDTMP and (166)HoCl(3) in wild-type rats was checked by scarification. SPECT imaging of (166)Ho-EDTMP was also performed in wild-type rats. A comparative accumulation study for (166)Ho-EDTMP and (166)HoCl(3) was performed for vital organs up to 48h. Significant bone accumulation (>70%) of the tracer in 48h was observed.