An open comparative study was performed at the Research Institute of Urology to examine sensibility and safety of technetium-labeled zoledronic acid drug Rezoscan,99mTc in patients with prostate cancer in case of skeletal lesions detected by bone scanning. Frequency of coincidence and discrepancy in bone scanning results when utilizing Rezoscan, 99mTc or Technifor, 99mTc was evaluated. Novel drug safety was assessed by virtue of analysis of undesirable events and side eff ects frequency. Obtained results show equal diagnostic value of assessed drug Rezoscan, 99mTc (1 h aft er administration) and Technifor, 99mTc (3 h aft er administration). No signifi cant diff erence in KDA minimal values 1,48 ± 0,29 vs 1,41 ± 0,52 (р = 0,668), and KDA maximal values 2,22 ± 1,19 vs 1,88 ± 0,82 (р = 0,381) was observed. As a result of clinical study, high effi cacy, safety and cost-eff ectiveness of Rezoscan, 99mTc were demonstrated for bone scanning in patients with pathological process in bones. Th e drug provided visualization of both osteoclastic and osteolytic metastases, enabled to carry out diff erential diagnostics of bone lesions, facilitate decision of treatment tactics and control outcomes thereof. Bone scanning utilizing Rezoscan, 99mTc allow to reduce examination time by 67% while obtain images of higher quality. Th e novel drug may be recommended for wide application in clinical practice in medical institutions of the Russian Federation.