Biomedical Imaging Laboratory, Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China.
Clin Nucl Med. 2023 Oct 1;48(10):847-852. doi: 10.1097/RLU.0000000000004757. Epub 2023 Jul 5.
We have developed a new pharmaceutical, ibandronic acid (IBA), and preliminarily demonstrated that it is an efficient bisphosphonate for the diagnosis and treatment of bone metastases. This study aims to examine the biodistribution and internal dosimetry of the diagnostic 68 Ga-DOTA-IBA in patients.
68 Ga-DOTA-IBA was intravenously injected based on 1.81-2.57 MBq/Kg into 8 patients with bone metastases. Each patient underwent 4 sequential static whole-body PET scans at 0.1, 0.45, 0.8, and 1.8 hours after injection. The acquisition time for each scan was 20 minutes with 10 bed positions. Image registrations and volume of interest delineation were first performed on Hermes, whereas percentage injected activity (%IA), absorbed dose, and effective dose were measured for source organs, using OLINDA/EXM v2.0. Dosimetrics for the bladder was based on a bladder voiding model.
No adverse effects were observed on all patients. After the injection, 68 Ga-DOTA-IBA rapidly accumulated in bone metastases and cleared from nonbone tissues, as indicated by visual analysis and %IA measured on the sequential scans. High activity uptake was presented in the expected target organs, that is, bone, red marrow, and the drug-excretion organs such as kidneys and bladder. The mean total body effective dose is 0.022 ± 0.002 mSv/MBq.
68 Ga-DOTA-IBA has high bone affinity and is promising in the diagnosis of bone metastases. Dosimetric results show that the absorbed doses for critical organs and total body are within the safety limit and with high bone retention. It also has the potential to be used in 177 Lu-therapy as a theranostic pair.
我们开发了一种新的药物伊班膦酸（IBA），并初步证明它是一种有效的双膦酸盐，可用于诊断和治疗骨转移。本研究旨在研究诊断用 68 Ga-DOTA-IBA 在患者中的生物分布和体内剂量。
8 例骨转移患者按 1.81-2.57MBq/Kg 的剂量静脉注射 68 Ga-DOTA-IBA。每位患者在注射后 0.1、0.45、0.8 和 1.8 小时进行 4 次连续静态全身 PET 扫描。每次扫描的采集时间为 20 分钟，共 10 个床位。首先在 Hermes 上进行图像配准和感兴趣区勾画，然后使用 OLINDA/EXM v2.0 测量源器官的注入活性百分比（%IA）、吸收剂量和有效剂量。膀胱剂量学基于膀胱排空模型。
所有患者均未观察到不良反应。注射后，68 Ga-DOTA-IBA 迅速在骨转移部位积聚，并从非骨组织中清除，这可以通过视觉分析和连续扫描测量的 %IA 来判断。预期的靶器官，即骨骼、红骨髓和药物排泄器官如肾脏和膀胱，均有高活性摄取。全身有效剂量的平均值为 0.022±0.002mSv/MBq。
68 Ga-DOTA-IBA 具有高骨亲和力，有望用于诊断骨转移。剂量学结果表明，关键器官和全身的吸收剂量均在安全范围内，且具有较高的骨滞留。它还有可能作为治疗诊断双联体用于 177 Lu 治疗。
