Safety of new 99mTc-radiopharmaceuticals

99mTechnetium (Tc) radiopharmaceuticals are special group of drugs due to their radioactive nature, low stability and their preparation in the hospital from generators and kits. New developments in this field draw the attention to quality and efficacy of these new products. 1407 99m Tc-radiopharmaceuticals were tested concerning their radiochemical purity. 53 preparations (about 1 % of all prepared radiopharmaceuticals) did not fulfill the required quality criteria, mainly recently developed kits with allow tin(II) content. Quality deficiencies were due to local factors in the hospital and not producer related. Investigations on 99m 99mTc-labelled monoclonal antibodies (MAb) showed identical metabolites for different MAb, the in vivo kinetics were dominated by the kind of MAb and the properties of Tc and were independent from the labeling method, that defined the pharmaceutical quality. New methods for the quantification of radio-TLC and for the polarographic determination of stannous ions were developed. This thesis shows, that with new developments of 99mTc-radiopharmaceuticals the requirements for the quality assurance have increased. Nevertheless 99m Tc-radiopharmaceuticals can be regarded as safe drugs. (author)