Oral therapy helped 42% of irradiated mice survive 30 days

The experiment began with mice exposed to a lethal dose of whole-body radiation. One hour later, researchers gave a single oral dose of XOlacta. 42% survived the 30-day study period, while untreated mice did not survive; the treatment also remained effective when delayed for 24 hours. The finding comes from researchers at the Fralin Biomedical Research Institute at VTC, led by senior author Robert Gourdie and first author Spencer Marsh.

XOlacta is designed to solve a practical delivery problem. It packages alpha-CT11, a therapeutic peptide, inside milk-derived extracellular vesicles—tiny particles naturally used by cells to transport biological molecules. The vesicles shield the peptide as it moves through the digestive system, making an oral dose possible. Imaging showed that they preferentially accumulated in radiation-damaged areas, including the brain, gut and bone marrow, while the treatment reduced injury to the small intestine and bone marrow.

The crucial test was whether protecting healthy tissue would also protect a tumor. In a mouse model of glioma brain cancer, XOlacta preserved radiation’s ability to suppress tumor growth. That matters because radiation therapy is used to treat approximately half of all cancer patients, and damage to healthy tissue can limit the dose physicians can safely deliver. Outside hospitals, severe whole-body radiation exposure also has no FDA-approved medical countermeasure.

So what changes, concretely? If later studies support the mouse results, an oral therapy stable at room temperature for a year or more could be stored in hospitals, homes and emergency stockpiles and given without specialized equipment. For cancer care, the same approach could potentially reduce radiation injury without weakening tumor treatment. The boundary is clear: the work is still preclinical. Lovelace Biomedical independently reproduced the mouse findings, but additional safety and large-animal studies are now underway before any human use.