ORIGINAL ARTICLE   

The Quarterly Journal of Nuclear Medicine and Molecular Imaging 2019 June;63(2):191-8

DOI: 10.23736/S1824-4785.16.02867-3

Copyright © 2016 EDIZIONI MINERVA MEDICA

lingua: Inglese

Copper-64 trastuzumab PET imaging: a reproducibility study

Jorge A. CARRASQUILLO ^{1, 2} ✉, Patrick G. MORRIS ^{3, 4}, John L. HUMM ⁵, Peter M. SMITH-JONES ^{1, 6}, Volkan BEYLERGIL ¹, Timothy AKHURST ^{1, 7}, Joseph A. O’DONOGHUE ⁵, Shutian RUAN ¹, Shanu MODI ³, Clifford A. HUDIS ³, Steven M. LARSON ^{1, 2, 8}

¹ Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA; ² Center for Radioimmunotherapy and Theranostics, Ludwig Center, Memorial Sloan Kettering Cancer Center, New York, NY, USA; ³ Breast Cancer Medicine Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA; ⁴ Department of Oncology, Beaumont Hospital, Dublin, Ireland; ⁵ Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA; ⁶ Department of Psychiatry, Stony Brook University, Stony Brook, NY, USA; ⁷ Peter MacCallum Cancer Center, Melbourne, Australia; ⁸ Sloan Kettering Institute, New York, NY, USA

BACKGROUND: The current study aims to assess the safety, pharmacokinetics, feasibility, and reproducibility of immunoPET imaging with copper-64 (64Cu) trastuzumab.
METHODS: An IV injection of 296-370 MBq/5 mg 64Cu-trastuzumab was administered between 1 to 4 hours after routine trastuzumab treatment. Whole-body PET scans were performed immediately post-injection and at 24 hours post-injection. Serial pharmacokinetics were performed. Of 11 patients (median age of 52; range of 31-61), 8 underwent a repeat study with 64Cu-trastuzumab to assess image and pharmacokinetic reproducibility. Patients were monitored for toxicity.
RESULTS: Patients experienced no allergic reactions or significant adverse effects from 64Cu-trastuzumab. Eight patients successfully completed a repeat 64Cu-trastuzumab study, with acceptable reproducibility of both the biodistribution and pharmacokinetic clearance. Study 1 versus study 2 showed similar serum concentration post-injection (mean 42.4±7.8 %ID/L vs. 44.7±12.6 %ID/L) and similar T1/2 (single exponential 46.1 vs. 44.2 hours), P>0.5. The volume of distribution (median 2.50 L) was in the range reported for trastuzumab and close to the estimated plasma volume of 2.60 L. Of 11 patients, two had 64Cu-trastuzumab localization corresponding to known tumor sites - one in liver and one in breast.
CONCLUSIONS: Preliminary results suggest that scanning with 64Cu-trastuzumab is feasible, safe, and reproducible. Tumor uptake of 64Cu-trastuzumab was observed, but tumor detection exhibited low sensitivity in this study in which imaging was performed in the presence of trastuzumab therapy.

KEY WORDS: Copper-64; Trastuzumab; Positron-emission tomography; Antibodies; Breast neoplasms