Abstract
TS14
Introduction: PLUVICTO™ (Lu-177 vipivotide tetraxetan) is a recently approved therapeutic radioligand indicated for treatment of patients with metastatic prostate cancer that is positive for prostate-specific membrane antigen (PSMA) receptors on imaging. From the three different administration methods highlighted in the prescribing information, Northwestern Memorial Hospital has chosen to implement the syringe method with a syringe pump technique. The objective of this study was to minimize the residual activity left after dose administration, therefore maximizing the net dose the patient receives, by evaluating impact of tubing length and saline flush technique by three configurations.
Methods: PLUVICTO was administered intravenously as a dose of 200 mCi and fitted with a syringe pump. There were three different configurations that were tested: long tubing with straight saline flush, short tubing with straight saline flush, and short tubing with straight saline flush and additional back flush. A total of 15 infusions were completed, with each configuration being tested a total of five times. Following each treatment, components for administration (syringe, two three-way stopcocks, infusion set, and saline flushes) were measured individually for residual using an ATOM500 dose calibrator.
Results: The average measured residual total for long tubing (straight saline flush), short tubing (straight saline flush), and short tubing (with additional back flush) were 1.03 mCi, 1.19 mCi, and 0.16 mCi respectively. A detailed summary of residual results can be found in Table 1.
Table 1: Mean Residual Results of PLUVICTO Infusion Methods
Residual (in µCi)
Syringe
2x 3-way Stopcocks
Infusion Set
Saline Flushes
Total Residual (in µCi)
Long Tubing, Straight Flush
539.2
487.8
9.4
0.2
1036.6
Short Tubing, Straight Flush
720.6
430.4
37.2
3.1
1191.3
Short Tubing, Additional Back Flush
156
5.6
2
0
163.6
Conclusions: Based on this study, the syringe method configuration of the short tubing with additional back flush decreased residual activity by 84% and 86% versus the long tubing with straight flush and short tubing with straight flush respectively. This technique has been adopted by Northwestern Memorial Hospital’s Nuclear Medicine Department and ensures the patient receives maximum net activity of the PLUVICTO treatment.