Radioprotection and Radiomitigation: From the Bench to Clinical Practice

Area of Science:

• Radiation biology
• Radiopharmaceutical chemistry

Background:

• Decades of research have sought effective radioprotective agents, but ideal solutions remain elusive.
• Ionizing radiation damage is largely due to free radicals, making radical scavengers a promising avenue.
• Current FDA-approved countermeasures are radiomitigators, not radioprotectors, highlighting a critical gap.

Purpose of the Study:

• To review the current landscape of radioprotectors and radiomitigators.
• To discuss molecules under development for clinical and nonclinical applications.
• To analyze assays for evaluating ionizing radiation's biological effects.

Main Methods:

• Literature review of radioprotective and radiomitigating agents.
• Analysis of FDA-approved radiation countermeasures.
• Discussion of ongoing research and development in radioprotection.

Main Results:

• Amifostine, a thiol-based compound, is an FDA-approved radioprotector but with limited use.
• Approved countermeasures like filgrastim, pegfilgrastim, and sargramostim are radiomitigators.
• No radioprotector for acute radiation syndrome (ARS) has been approved for pre-exposure use.

Conclusions:

• A significant need exists for effective radioprotectors, especially for ARS.
• Distinguishing between radioprotectors and radiomitigators is crucial for therapeutic strategies.
• Ongoing development targets novel molecules and improved evaluation assays for radiation countermeasures.