RT Journal Article SR Electronic T1 Phase II, open label, multi-dose study of 89-Zr-Df-IAB22M2C (CD8 Immuno-PET Tracer): technical handling and injection instructions for optimal tracer administration. JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 3004 OP 3004 VO 62 IS supplement 1 A1 Kaylee Allred A1 Quinten Sanders A1 Monica Prince A1 Ron Korn A1 Ian Wilson A1 William Le A1 Avital Weiss A1 Amanda Abbott A1 David Hays YR 2021 UL http://jnm.snmjournals.org/content/62/supplement_1/3004.abstract AB 3004Objectives: ImaginAb’s multicenter, open-labeled Phase II study (IAB-CD8-201) includes the administration of 8-9ml of 1.0 or 3.0 mCi 89Zr-Df-IAB22M2C (CD8 PET Tracer) prior to the onset and 4 to 6 weeks after the start of cancer immunotherapy (IOT). 89Zr-radiolabeled PET tracers are distinctive from 18F agents given the difference in the positron fraction, energy emissions and longer half-life of 89Zr. We report here our experience on the handling and injection of 89Zr-Df-IAB22M2C in an optimal manner. Methods: A single institutional experience is reported at Central Arkansas Radiation Therapy Institute (CARTI), the leading site with over 25 injections. The protocol (NCT03802123) was approved by a Central IRB and CARTI radiation safety committee. All patients signed informed consent prior to study participation and receiving the first radiotracer dose. The radiotracer was received, processed, surveyed and stored at 2-8 ºC prior to administration per site internal standards. All radioactivity measurements were performed in a calibrated dose calibrator using the 89Zr energy setting and timed to the atomic clock setting. No specific patient preparation was necessary (i.e. no fasting or sedentary behavior) prior to injection, a peripheral 22 gauge IV line was securely placed and connected to 30” tubing attached to a 3-way stop cock primed with saline. Once the injected dose was brought to room temperature, a 20–22-gauge needle was attached to an empty syringe with a plastic stopper to remove the required volume and dose and the measurement was recorded. The dose syringe was then attached to one side of the 3-way stopcock and the control knob positioned to allow for open flow of the CD8 PET Tracer injection into the patient’s extension tubing via an infusion pump according to the manufacture’s guidelines that was set to an infusion rate of 5-10 minutes. At completion, a 60cc syringe filled with normal saline was attached to the 3-way stopcock to flush the tubing and CD8 PET Tracer syringe. All IV tubing was subsequently removed from the patient, and residual activity in the dose syringe and IV tubing (placed in a large glove) was measured and recorded. Results: Despite the difference in positron fraction (23%), energy emission (Emax=897keV), and half-life (3.3 d) of 89Zr compared to 18F (97%, 634 keV, 110 m, respectively), the low dose (1-3 mCi) of 89Zr administered allowed for routine radiation safety procedures similar to 18F. However, unlike 18F in routine PET tracers, the CD8 PET Tracer has viscous properties and required the use of a syringe with a plastic stopper for optimal injection with less residual activity compared to a syringe with a rubber stopper. Radiation exposure to technical personnel was similar to 18F agents. Conclusions: Due to the required infusion time and the minimal dose amount, it is imperative to have a consistent and effective process of administering the 89Zr-Df-IAB22M2C CD8 PET Tracer correctly. We have optimized the method to administer this tracer while minimizing any residual activity remaining in the tubing and syringes. By following the procedures mentioned above, we have been able to avoid any radioactive contamination or additional personnel exposure while ensuring that the patient receives an adequate dose in an effective manner.