Production, isolation, and shipment of clinically relevant quantities of astatine-211: A simple and efficient approach to increasing supply

The alpha emitter astatine-211 (At-211) is a promising candidate for cancer treatment based on Targeted Alpha (alpha) Therapy (TAT). A small number of facilities, distributed across the United States, are capable of accelerating alpha-particle beams to produce At-211. However, challenges remain regarding strategic methods for shipping At-211 in a form adaptable to advanced radiochemistry reactions and other uses of the radioisotope.Purpose: Our method allows shipment of At-211 in various quantities in a form convenient for further radiochemistry.Procedures: For this study, a 3-octanone impregnated Amberchrom CG300M resin bed in a column cartridge was used to separate At-211 from the bismuth matrix on site at the production accelerator (Texas A&M) in preparation for shipping. Aliquots of 6 M HNO3 containing up to approximate to 2.22 GBq of At-211 from the dissolved target were successfully loaded and retained on columns. Exempt packages (<370 MBq) were shipped to a destination radiochemistry facility, University of Texas MD Anderson Cancer Center, in the form of a convenient air-dried column. Type A packages have been shipped overnight to University of Alabama at Birmingham.Main findings: Air-dried column hold times of various lengths did not inhibit simple and efficient recovery of At-211. Solution eluted from the column was sufficiently high in specific activity to successfully radiolabel a model compound, 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)aniline (1), with At-211. The method to prepare and ship At-211 described in this manuscript has also been used to ship larger quantities of At-211 a greater distance to University of Alabama at Birmingham.Principal conclusions: The successful proof of this method paves the way for the distribution of At-211 from Texas A&M University to research institutions and clinical oncology centers in Texas and elsewhere. Use of this simple method at other facilities has the potential increase the overall availability of At-211 for preclinical and clinical studies.

Automated summary

This article presents a method for shipping At-211 radioisotope in a convenient form for further radiochemistry, addressing challenges in transportation for advanced reactions and other uses. The method is simple and efficient, and has been successfully implemented at multiple locations.