FAST-02, a single-arm, FDA investigational-device-exemption (IDE)-approved feasibility trial, is testing proton FLASH radiotherapy — an experimental technique that delivers a full course of radiation in under 1 second, more than 100 times faster than conventional radiotherapy — to treat painful bone metastases in the thorax (excluding the spine), in patients with 1 to 3 such metastases regardless of their cancer’s primary origin. In preclinical (laboratory and animal) studies, delivering radiation at this ultra-high dose rate has shown the potential to reduce damage to healthy surrounding tissue while maintaining effective tumor control — the hypothesis this human feasibility trial is testing. The trial protocol was published in the journal Radiation Oncology (DOI 10.1186/s13014-024-02419-4). As of this record, FAST-01 and FAST-02 are the only in-human proton FLASH trials conducted worldwide; this remains an experimental technique, not yet a standard or widely available radiotherapy option, and this record makes no claim of proven superiority over conventional radiotherapy — that would require larger, comparative, longer-follow-up trials.

A preclinical mouse study reports that a tardigrade-inspired (Dsup) mRNA strategy protects healthy tissue during radiation exposure. Primary publication: PMID 40011582, https://pubmed.ncbi.nlm.nih.gov/40011582/, DOI https://doi.org/10.1038/s41551-025-01360-5. This is experimental, preclinical, mouse-model work only. It must NOT be summarized to imply cancer patients can currently receive Dsup treatment, and must NOT be called a proven prevention of human radiotherapy side effects — no human data was supplied by the governing directive, and none is implied here. [Identifiers as supplied, attributed to independent verification outside this environment — not independently re-verified live here.]