Synthesis, preclinical evaluation, and first-in-human study of Al18F-PSMA-Q for prostate cancer imaging

Blocking Studies to Evaluate Receptor-Specific Radioligand Binding in the CAM Model by PET and MR Imaging

“…Our data concerning dose-dependent inhibition were in excellent agreement with the expectations based on the K i value of 0.275 nM for the inhibitor 2-PMPA reported in the literature [ 37 , 38 ]. The small molecule 2-PMPA is a common inhibitor of PSMA and is regularly used for inhibition studies [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 ], with no side effects described at the concentrations used in this study. The affinity of the compound is about two orders of magnitude higher compared to [ 18 F]siPSMA-14, with an inhibitory concentration 50% (IC50) of (13.0 ± 1.2) nM based on patent information [ 53 ], and thus was a suitable inhibitor for the present study.…”

“…Specificity is usually demonstrated by blocking studies using either the compound itself in unlabeled form or a competing inhibitor. The blocking agent is administered in excess through a separate injection by pre-dosing 10 min to 30 min prior to compound application [ 48 , 49 , 50 , 51 , 52 ] or by co-injection with the substance to be analyzed [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. Due to the lack of information on the pharmacokinetics of the inhibitor in the CAM model so far and also to demonstrate the feasibility of multiple catheter applications in this study, we opted for preinjection of the inhibitor 20 min prior to the radiolabeled compound.…”

Increased Prostate-Specific Membrane Antigen Uptake in a Gallbladder Stone

“…Consequently, he was referred for an Al 18 F-prostatespecific membrane antigen (PSMA) Q PET/CT scan aimed at localizing the potential recurrent lesions. 1 The Al 18 F-PSMA-Q PET/CT (A, MIP) scan revealed no recurrent or metastatic lesions. However, the transverse (B) and coronal (C) CT images, corresponding PET (D and E) images, and fused (F and G) images showed focal PSMA uptake with SUV max of 4.2 in a large gallbladder stone (arrows) measuring 2.9 Â 2.3 Â 2.1 cm.…”

“…After the external beam radiotherapy, there was a gradual increase in his PSA level, rising from 0.069 ng/mL to 0.164 ng/mL over a period of 10 months. Consequently, he was referred for an Al 18 F–prostate-specific membrane antigen (PSMA) Q PET/CT scan aimed at localizing the potential recurrent lesions 1 . The Al 18 F-PSMA-Q PET/CT ( A , MIP) scan revealed no recurrent or metastatic lesions.…”

State-of-the-art of nuclear medicine and molecular imaging in China: after the first 66 years (1956–2022)

“…In the final published special issue, there are more than 40 articles total, which include 6 review articles [ 4 , 6 – 10 ] and this editorial, with the remaining being research articles. According to the standard EJNMMI list of topics, these research articles were divided into the following categories: advanced image analyses [ 11 – 13 ], preclinical imaging [ 14 – 26 ], translational research [ 27 – 30 ], neurology [ 31 , 32 ], cardiology [ 33 ], and oncology [ 34 – 47 ]. Due to the large number of accepted manuscripts, which is significantly more than the typical number of articles per EJNMMI issue, many invited contributions were published in various issues before this EJNMMI special issue, which include 2 review articles [ 48 , 49 ], many research articles [ 50 – 62 ], and 1 invited editorial [ 63 ].…”