Valion Bio Secures AFRRI/NIAID PBI-BM2.5 Protocol for Entolimod GI-ARS Evaluation
VBIO•Valion Bio’s lead candidate Entolimod will undergo evaluation under a proprietary PBI-BM2.5 murine model designed by AFRRI/NIAID to assess survival efficacy at a lethal 14.6 Gy dose, meeting FDA Animal Rule criteria. This protocol de-risks regulatory approval and targets a GI-ARS market projected to exceed $7.8 billion by 2032.
1. Protocol Design and Model Specifications
AFRRI and NIAID have finalized a survival efficacy protocol for Entolimod using a partial body irradiation model that spares 2.5% of bone marrow, delivering a lethal LD50/30 dose of 14.6 Gy in mice. This design isolates gastrointestinal effects from hematopoietic failure, creating a clear efficacy signal for intestinal recovery.
2. Regulatory Significance and Data Generation
The PBI-BM2.5 model meets FDA Animal Rule criteria, enabling approval based on rigorous nonclinical efficacy data without human trials. Completion of this protocol de-risks Entolimod’s licensure path and fulfills U.S. government priorities for radiation countermeasures that serve both prophylactic and therapeutic roles.
3. Market Opportunity and Next Steps
No FDA-approved treatments currently address GI-ARS, representing a multi-billion-dollar gap. The GI-ARS segment is forecast to grow from $5.47 billion in 2025 to $7.80 billion by 2032, with North America accounting for 46% of revenue. Valion Bio will now generate pivotal animal data to support submissions under the Animal Rule.
