Safety and efficacy of a novel hepatobiliary MR contrast agent, Gd‐DTPA‐DeA: Results of phase I and phase II clinical trials

Purpose To assess the safety, effective dose, and efficacy of a novel hepatobiliary MR contrast agent Gd‐DTPA‐DeA for imaging liver tumors, from the clinical phase I and phase II trials in Japan. Materials and Methods In a phase I trial, 33 healthy volunteers were intravenously administered a single dose of 0.03–10 μmol/kg of Gd‐DTPA‐DeA. In a nationwide phase II trial, 80 patients suspected to have hepatic mass were divided into three dosing groups: 2.5, 5.0, or 7.5 μmol/kg. T1‐weighted gradient echo images were obtained before and after Gd‐DTPA‐DeA administration at three time points. Liver signal‐to‐noise ratio (SNR) and lesion‐liver contrast‐to‐noise ratio (CNR) were calculated at each time point. A reading committee evaluated the contrast, diagnostic, and overall efficacy using a five‐point scale. Results In a phase I trial, dosages up to 10 μmol/kg were well tolerated by healthy volunteers. In a phase II trial, the contrast, diagnostic, and overall efficacy increased dose‐dependently. The overall efficacy was 63.0%, 85.2%, and 88.0%, for 2.5, 5, and 7.5 μmol/kg, respectively. Liver SNR and CNR increase was greater at late phase than at early phase. No serious adverse events occurred. Conclusion Gd‐DTPA‐DeA is a well‐tolerated and promising contrast agent for liver MR imaging. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.