Clinical Trial with Sodium ^99mTc-Pertechnetate Produced by a Medium-Energy Cyclotron: Biodistribution and Safety Assessment in Patients with Abnormal Thyroid Function

Abstract

A single-site prospective open-label clinical study with cyclotron-produced sodium Tc-pertechnetate (Tc-NaTcO) was performed in patients with indications for a thyroid scan to demonstrate the clinical safety and diagnostic efficacy of the drug and to confirm its equivalence with conventional Tc-NaTcO eluted from a generator. Tc-NaTcO was produced from enriched Mo (99.815%) with a cyclotron (24 MeV; 2 h of irradiation) or supplied by a commercial manufacturer (bulk vial eluted from a generator). Eleven patients received 325 ± 29 (mean ± SD) MBq of the cyclotron-producedTc-NaTcO, whereas the age- and sex-matched controls received a comparable amount of the generator-derived tracer. Whole-body and thyroid planar images were obtained for each participant. In addition to the standard-energy window (140.5 keV ± 7.5%), data were acquired in lower-energy (117 keV ± 10%) and higher-energy (170 keV ± 10%) windows. Vital signs and hematologic and biochemical parameters were monitored before and after tracer administration. Cyclotron-producedTc-NaTcO showed organ and whole-body distributions identical to those of conventional Tc-NaTcO and was well tolerated. All images led to a clear final diagnosis. The fact that the number of counts in the higher-energy window was significantly higher for cyclotron-produced Tc-NaTcO did not influence image quality in the standard-energy window. Image definition in the standard-energy window with cyclotron-produced Tc was equivalent to that with generator-elutedTc and had no particular features allowing discrimination between the Tc production methods. The systemic distribution, clinical safety, and imaging efficacy of cyclotron-produced Tc-NaTcO in humans provide supporting evidence for the use of this tracer as an equivalent for generator-eluted Tc-NaTcO in routine clinical practice.

Internal radiation dose assessment of radiopharmaceuticals prepared with cyclotron‐produced 99mTc

“…Selivanova et al . reported a 7.58% increase in Tc‐pertechnetate effective dose, when assuming an irradiation at 24 MeV for 2 h and an injection time 6 h after EOB; this value is higher than the 5.30% obtained in this work for the same Mo target and injection time.…”

“…Additionally, it was demonstrated that rats scatter‐corrected images of myocardial perfusion and bone obtained after injection of radiopharmaceuticals labeled with either CP‐ 99m Tc or GP‐ 99m Tc were comparable . Selivanova et al . confirmed these results and demonstrated that sodium pertechnetate produced by cyclotron and generator had similar whole body biodistribution in patients.…”

Development of Novel Alumina by Solid-State Reaction for 99Mo/99mTc Adsorbent Material

“…The second method is mainly carried out in developed countries possessing a proper cyclotron for 99 Mo production. The latter method is simpler because a research reactor is not required, however, the production cost is more expensive (Selivanova et al, 2016). Both methods produce lower specific activity 99 Mo compared to that of production from fission uranium.…”

Influence Of Drying Time And Temperature On Zirconium-Based Material (ZBM) Properties For 99Mo/99mTc Generator Development

“…R. A. Pillai, Dash, and Knapp 2013). Mo is obtained from natural Molybdenum (MoO 3 ) irradiated by either cyclotron or research reactor (M. R. a Pillai, Dash, and Knapp 2015;Selivanova et al 2016;Amin et al 2014). The advantages of nonfission 99 Mo compared to fission 99 Mo are the easy handling of the waste, the low radioactivity waste, and the simple post-irradiation method.…”