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. 2022 Oct;24(5):710-720.
doi: 10.1007/s11307-022-01720-6. Epub 2022 Mar 29.

Preliminary Evaluation of 68Ga-P16-093, a PET Radiotracer Targeting Prostate-Specific Membrane Antigen in Prostate Cancer

Hwan Lee  1 , Joshua S Scheuermann  1 , Anthony J Young  1 , Robert K Doot  1 , Margaret E Daube-Witherspoon  1 , Erin K Schubert  1 , Matthew A Fillare  1 , David Alexoff  2 , Joel S Karp  1 , Hank F Kung  2 , Daniel A Pryma  3
Affiliations

Preliminary Evaluation of 68Ga-P16-093, a PET Radiotracer Targeting Prostate-Specific Membrane Antigen in Prostate Cancer

Hwan Lee et al. Mol Imaging Biol. 2022 Oct.

Abstract

Purpose: Prostate-specific membrane antigen (PSMA) is a promising molecular target for imaging of prostate adenocarcinoma. 68Ga-P16-093, a small molecule PSMA ligand, previously showed equivalent diagnostic performance compared to 68Ga-PSMA-11 PET/CT in a pilot study of prostate cancer patients with biochemical recurrence (BCR). We performed a pilot study for further characterization of 68Ga-P16-093 including comparison to conventional imaging.

Procedures: Patients were enrolled into two cohorts. The biodistribution cohort included 8 treated prostate cancer patients without recurrence, who underwent 6 whole body PET/CT scans with urine sampling for dosimetry using OLINDA/EXM. The dynamic cohort included 15 patients with BCR and 2 patients with primary prostate cancer. Two patients with renal cell carcinoma were also enrolled for exploratory use. A dynamic PET/CT was followed by 2 whole body scans for imaging protocol optimization based on bootstrapped replicates. 68Ga-P16-093 PET/CT was compared for diagnostic performance against available 18F-fluciclovine PET/CT, 99mTc-MDP scintigraphy, diagnostic CT, and MRI.

Results: 68Ga-P16-093 deposited similar effective dose (0.024 mSv/MBq) and lower urinary bladder dose (0.064 mSv/MBq) compared to 68Ga-PSMA-11. The kidneys were the critical organ (0.290 mSv/MBq). While higher injected activities were preferable, lower injected activities at 74-111 MBq (2-3 mCi) yielded 80% retention in signal-to-noise ratio. The optimal injection-to-scan interval was 60 min, with acceptable delay up to 90 min. 68Ga-P16-093 PET/CT showed superior diagnostic performance over conventional imaging with overall patient-level lesion detection rate of 71%, leading to a change in management in 42% of the patients.

Conclusions: Based on its favorable imaging characteristics and diagnostic performance in prostate cancer, 68Ga-P16-093 PET/CT merits further investigation in larger clinical studies.

Keywords: Biochemical recurrence; Positron emission tomography computed tomography; Prostate cancer; Prostate-specific membrane antigen.

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References

    1. Davis MI, Bennett MJ, Thomas LM, Bjorkman PJ (2005) Crystal structure of prostate-specific membrane antigen, a tumor marker and peptidase. Proc Natl Acad Sci U S A 102:5981–5986 - DOI
    1. Zippel C, Ronski SC, Bohnet-Joschko S, Giesel FL, Kopka K (2020) Current status of PSMA- radiotracers for prostate cancer: data analysis of prospective trials listed on ClinicalTrials.gov. Pharmaceuticals (Basel) 13:12 - DOI
    1. Rhee H, Blazak J, Tham CM et al (2016) Pilot study: use of gallium-68 PSMA PET for detection of metastatic lesions in patients with renal tumour. EJNMMI Res 6:76 - DOI
    1. Hofman MS, Hicks RJ, Maurer T, Eiber M (2018) Prostate-specific membrane antigen PET: clinical utility in prostate cancer, normal patterns, pearls, and pitfalls. Radiographics 38:200–217 - DOI
    1. Han S, Woo S, Kim YJ, Suh CH (2018) Impact of (68)Ga-PSMA PET on the management of patients with prostate cancer: a systematic review and meta-analysis. Eur Urol 74:179–190 - DOI

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