IKCS 2019: Novel ImmunoPET/CT Under Study in Renal Cell Carcinoma
Posted: Friday, December 13, 2019
A new study is exploring the use of a novel radiotracer, 89Zr-DFO-atezolizumab, to allow for the combination of the specificity of anti–PD-L1 antibodies with the sensitivity and qualification of PET in the development of immunoPET. Isaac A. Bowman, MD, of The University of Texas Southwestern Medical Center in Dallas, presented the methods of this study at the 2019 International Kidney Cancer Symposium (IKCS) in Miami.
The development of immunoPET is aimed at allowing real-time monitoring of the interaction between tumors and its microenvironment in vivo, which could be correlated to the clinical response and toxicity of immune checkpoint inhibitors, according to the investigators. They will conjugate the anti–PD-L1 antibody atezolizumab to zirconium-89 via desferrioxamine (DFO) and administer the radiotracer to two cohorts of about 20 patients. One cohort will consist of patients with localized renal cell carcinoma before undergoing surgery, and the other cohort will comprise patients with metastatic renal cell carcinoma who have not yet received immune checkpoint inhibitors.
All patients will receive an intravenous injection of 89Zr-DFO-atezolizumab followed by a PET/ CT scan about 1 week later. Repeat 89Zr-DFO-atezolizumab PET/CT scans will occur if disease recurrence is documented or disease progression or toxicity occurs with an immune checkpoint inhibitor. These patients will then be followed for up to 5 years.
To be enrolled in the study, patients must have either pathologically confirmed renal cell carcinoma or imaging suggestive of localized renal cell carcinoma. Patients will be excluded from the study if they are currently being treated with an immune checkpoint inhibitor or immune checkpoint inhibition is contraindicated. Patient accrual began in August 2019.
Disclosure: The full disclosures of the study authors can be found at https://www.kidneycancer.org/.