Pilot-phase PET/CT study targeting integrin αvβ6 in pancreatic cancer patients using the cystine-knot peptide-based 18F-FP-R01-MG-F2.

Purpose A novel cystine-knot peptide-based PET radiopharmaceutical, 18F-FP-R01-MG-F2 (knottin), was developed to selectively bind to human integrin αvβ6 which is overexpressed in pancreatic cancer. The purpose of this study is to evaluate the safety, biodistribution, dosimetry, and lesion uptake of 18F-FP-R01-MG-F2 in patients with pancreatic cancer. Methods Fifteen patients (6 men, 9 women) with histologically confirmed pancreatic cancer were prospectively enrolled and underwent knottin PET/CT between March 2017 and February 2021 (ClinicalTrials.gov Identifier NCT02683824). Vital signs and laboratory results were collected before and after the imaging scans. Maximum standardized uptake values (SUVmax) and mean SUV (SUVmean) were measured in 24 normal tissues and pancreatic cancer lesions for each patient. From the biodistribution data, the organ doses and whole-body effective dose were calculated using OLINDA/EXM software. Results There were no significant changes in vital signs or laboratory values that qualified as adverse events or serious adverse events. At 1 h post-injection, areas of high 18F-FP-R01-MG-F2 uptake included the pituitary gland, stomach, duodenum, kidneys, and bladder (average SUVmean: 9.7-14.5). Intermediate uptake was found in the normal pancreas (average SUVmean: 4.5). Mild uptake was found in the lungs and liver (average SUVmean Conclusion 18F-FP-R01-MG-F2 is a safe PET radiopharmaceutical with an effective dose comparable to other diagnostic agents. Evaluation of the primary pancreatic cancer and distant metastases with 18F-FP-R01-MG-F2 PET is feasible, but larger studies are required to define the role of this approach. Trial registration NCT02683824.