Radioactivity distribution in the blood and urine of patients receiving systemic therapy with a <sup>177</sup>Lu radiopharmaceutical and local (intra-articular) therapy with a <sup>188</sup>Re radiopharmaceutical

Pharmacokinetic parameters are important for calculating the absorbed dose; they also provide an indirect measure of in vivo stability a radiopharmaceutical. The aim study was to determine excretion rate activity 177 Lu-DOTA-PSMA-617 and MCA 5–10 microns, 188 Re, from blood urine patients undergoing systemic local radiotherapy clinical trials. Materials methods: involved radiometry samples 12 male with metastatic prostate cancer 20 both sexes chronic synovitis, selected after experimental radiopharmaceuticals respectively. measured using dose calibrator gamma counter. Results: Lu 36.0–89.3%, 10.4–55.7%, 14.6–32.8%, 10.6–35.7%, 7.3–25.1% at 5 minutes 1, 3, 6 8 hours administration Lu-DOTA-PSMA-617, 48-hour varied within 34.4–88.8% 0.15–2.91% Re. Conclusions: maximum values (9.6–25.1%) corresponded injected radiopharmaceutical product. low Re urinary intra-articular is indication quality obtained pharmacokinetic show high medicinal products. results will be used calculate doses patients.