A rapid and safe infusion protocol for lutetium-177 peptide receptor radionuclide therapy

Abstract

Purpose: Peptide receptor radionuclide therapy (PRRT) with ¹⁷⁷Lu-labelled somatostatin analogues in patients with somatostatin-receptor expressing tumors is often performed using administration protocols prescribing a 30 minutes infusion time. The most often used method of infusion is the gravity method, by which the complete dose is effectively administered exponentially. However, there is no evidence to explicitly support an infusion time of 30 minutes. This study aims to investigate the safety of an infusion time of less than 5 minutes. Methods: A cohort study was performed, examining the biochemical and clinical toxicity after PRRT when using a fast infusion protocol with a maximum infusion time of 5 minutes. Data on patient characteristics, laboratory tests, follow-up visits and pre- and post-treatment imaging using ⁶⁸Ga-DOTA-TOC PET/CT from patients treated with PRRT at the University Medical Center Utrecht (UMC Utrecht) were collected. All patients receiving PRRT using the fast-infusion protocol were included. If no laboratory or clinical follow-up was available, patients were excluded. In addition, a laboratory experiment was performed, simulating the standard-infusion protocol using the gravity method. Results: 31 patients were included, who were treated using the fast infusion protocol. Clinical toxicity mainly consisted of grade 1/2 fatigue (87.1%) and grade 1 nausea and/or vomiting (67.7%) during follow-up. No acute or long term clinical toxicity possibly related to the fast infusion protocol was reported. Grade 3/4 hematological toxicity occurred after PRRT in one patient (3.2%). No grade 3/4 renal toxicity occurred. The laboratory experiment showed that when using the gravity method for infusion, half of the activity is infused after 3.5 minutes, and 95% is infused within 15 minutes. Conclusion: A faster infusion of PRRT using an infusion time of less than 5 minutes is safe and feasible in clinical practice.