Clinical Translation of a Dual-Integrin αvβ3- and CD13-Targeting PET Tracer

Angiogenesis is essential in the development and progression of tumors. This study aimed to investigate the clinical application of 68 Ga-labeled heterodimeric peptide ( 68 Ga-HX01) targeting integrin αvβ3 and CD13 in tumor neovascularization.

Six healthy volunteers were recruited to study the biodistribution, pharmacokinetics, and radiation of 68 Ga-HX01. Twelve patients with various malignancies were enrolled to seek the preliminary clinical value of 68 Ga-HX01. In healthy volunteers, SUVs of each major organ on 68 Ga-HX01 PET were measured. The clinical data, lesion numbers, and uptake were recorded in patients. The integrin αvβ3 and CD13 expression of the resected tumors was checked via immunohistochemistry staining.

With a mean injected dose of 167.98 ± 26.32 MBq, 68 Ga-HX01 was well tolerated and safe without side effects in 6 healthy volunteers. The radiation absorbed effective dose of 68 Ga-HX01 was 1.94 × 10 -2 mSv/MBq, and the urinary bladder wall held the highest absorbed effective dose (0.15 ± 5.87 × 10 -2 mSv/MBq). In 12 patients with various malignancies, 68 Ga-HX01 PET could clearly visualize the lesions from the surrounding tissues. The SUV max values in tumors were significantly higher than those in the surrounding tissues ( P < 0.05). A positive correlation trend between tumor SUV max and semiquantitative integrin αvβ3 and CD13 expression was determined ( P < 0.05).

For clinical use, 68 Ga-HX01 is safe with low radiation absorbed effective dose. It also indicates the efficiency of dual integrin αvβ3 and CD13-targeting PET radiotracer in tumor diagnosis, which may assist in patient prognosis and selecting eligible patients for antiangiogenic therapy.