title: [Phase I clinical study of 99mTc-ECD].
abstract: A phase I clinical study of 99mTc-L,L-ethyl cysteinate dimer (99mTc-ECD) was carried out in 3 normal volunteers. There was no significant change in vital signs and laboratory parameters attributing to the radiopharmaceutical. 99mTc-ECD was rapidly taken up by the brain, reaching the maximum peak activity within 1 min after the injection and remained relatively constant over several hours. The brain uptake of 99mTc-ECD at 5 min was 5.4 +/- 0.5% which decreased to 5.0 +/- 0.3% by 65 min. 99mTc-ECD cleared rapidly from other organs. The primary excretion route was through the kidneys. Cumulative 99mTc activity in the urine at 90 min and 24 hr were 60.2 +/- 7.3% and 88.5 +/- 10.3%, respectively. The critical organ was the bladder wall with an estimated radiation dose of 0.073 mGy/MBq, which was acceptable value. Clear SPECT images were obtained at 30, 90 and 150 min postinjection. In conclusion, 99mTc-ECD is a safe and promising radiopharmaceutical for the evaluation of regional cerebral blood flow.
authors.affiliation: Department of Radiology, Keio University Hospital, Tokyo.
authors.forename: A
authors.initials: A
authors.lastname: Kubo
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Tsukatani
authors.forename: T
authors.initials: T
authors.lastname: Sanmiya
authors.forename: S
authors.initials: S
authors.lastname: Shimizu
authors.forename: K
authors.initials: K
authors.lastname: Yokoyama
authors.forename: S
authors.initials: S
authors.lastname: Hashimoto
authors.forename: K
authors.initials: K
authors.lastname: Torizuka
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D002560:Cerebrovascular Circulation; D003545:Cysteine / Q000031:analogs & derivatives*; D006801:Humans; D007668:Kidney / Q000378:metabolism; D008297:Male; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon; D001743:Urinary Bladder / Q000378:metabolism
chemical_list: D015609:Organotechnetium Compounds; C059659:technetium Tc 99m bicisate; D003545:Cysteine