First-in-man evaluation of 2 high-affinity PSMA-avid small molecules for imaging prostate cancer.

Published

Journal Article

UNLABELLED: This phase 1 study was performed to determine the pharmacokinetics and ability to visualize prostate cancer in bone, soft-tissue, and the prostate gland using (123)I-MIP-1072 and (123)I-MIP-1095, novel radiolabeled small molecules targeting prostate-specific membrane antigen. METHODS: Seven patients with a documented history of prostate cancer by histopathology or radiologic evidence of metastatic disease were intravenously administered 370 MBq (10 mCi) of (123)I-MIP-1072 and (123)I-MIP-1095 2 wk apart in a crossover trial design. (123)I-MIP-1072 was also studied in 6 healthy volunteers. Whole-body planar and SPECT/CT imaging was performed and pharmacokinetics studied over 2-3 d. Target-to-background ratios were calculated. Absorbed radiation doses were estimated using OLINDA/EXM. RESULTS: (123)I-MIP-1072 and (123)I-MIP-1095 visualized lesions in soft tissue, bone, and the prostate gland within 0.5-1 h after injection, with retention beyond 48 h. Target-to-background ratios from planar images averaged 2:1 at 1 h, 3:1 at 4-24 h, and greater than 10:1 at 4 and 24 h for SPECT/CT. Both agents cleared the blood in a biphasic manner; clearance of (123)I-MIP-1072 was approximately 5 times faster. (123)I-MIP-1072 was excreted in the urine, with 54% and 74% present by 24 and 72 h, respectively. In contrast, only 7% and 20% of (123)I-MIP-1095 had been renally excreted by 24 and 72 h, respectively. Estimated absorbed radiation doses were 0.054 versus 0.110 mGy/MBq for the kidneys and 0.024 versus 0.058 mGy/MBq for the liver, for (123)I-MIP-1072 and (123)I-MIP-1095, respectively. CONCLUSION: (123)I-MIP-1072 and (123)I-MIP-1095 detect lesions in soft tissue, bone, and the prostate gland at as early as 1-4 h. These novel radiolabeled small molecules have excellent pharmacokinetic and pharmacodynamic profiles and warrant further development as diagnostic and potentially when labeled with (131)I therapeutic radiopharmaceuticals.

Full Text

Duke Authors

Cited Authors

  • Barrett, JA; Coleman, RE; Goldsmith, SJ; Vallabhajosula, S; Petry, NA; Cho, S; Armor, T; Stubbs, JB; Maresca, KP; Stabin, MG; Joyal, JL; Eckelman, WC; Babich, JW

Published Date

  • March 2013

Published In

Volume / Issue

  • 54 / 3

Start / End Page

  • 380 - 387

PubMed ID

  • 23303962

Pubmed Central ID

  • 23303962

Electronic International Standard Serial Number (EISSN)

  • 1535-5667

International Standard Serial Number (ISSN)

  • 0161-5505

Digital Object Identifier (DOI)

  • 10.2967/jnumed.112.111203

Language

  • eng