New Compound Blocks Ebola Virus Entry by Stabilizing Viral Protein

Researchers at the University of Minnesota and collaborating institutions discovered MWAC-3634, a small molecule that blocks Ebola virus infection by stabilizing its entry protein rather than destabilizing it. Published in Nature Communications, the preclinical study demonstrates that oral administration of the compound provides strong protection, achieving a 69% oral bioavailability relative to intravenous dosing and significantly improving survival rates.

The discovery marks a departure from conventional antiviral strategies. While previous experimental compounds destabilized the Ebola entry protein, MWAC-3634 locks the protein in a stable state. This stabilization prevents the shape changes required for the virus to fuse with and enter a host cell. By freezing the protein in place, the molecule halts the infection cycle at one of its earliest stages, offering a novel pharmacological blueprint for future therapeutic development.

In Plain English: The Clinical Takeaway

• Mechanism of Action: MWAC-3634 binds directly to a pocket on the Ebola entry protein, holding it in a stable state so the virus cannot change shape to enter a cell.
• Oral Delivery Potential: This small molecule achieved a 69% oral bioavailability in preclinical models, paving the way for easier administration.
• Potency and Safety: The compound inhibited authentic Ebola virus infection with an IC50 (half-maximal inhibitory concentration) of 0.65 nM, demonstrating potency with no detectable cellular toxicity under tested conditions.

Screening Billions of Molecules Using DNA-Encoded Chemistry

The identification of MWAC-3634 required screening approximately 4.73 billion molecules using DNA-Encoded Chemistry Technology (DEL). Led by the Midwest Antiviral Drug Discovery (AViDD) Center based at the University of Minnesota, the multi-institutional effort brought together researchers from Baylor College of Medicine, Boston University, and the University of Florida Scripps Institute.

This scale allowed teams to explore chemical space far beyond a conventional screen.

Following the initial screen, stereochemical analysis pinpointed the most active form. Peter Dosa, PhD, research associate professor of medicinal chemistry at the University of Minnesota, explained that identifying this specific form substantially increased the compound’s overall potency.

Molecular Stabilization Versus Viral Fusion

High-resolution structural analysis revealed the exact binding topography of MWAC-3634.

“This compound works in the opposite way from previously studied Ebola entry inhibitors,” Dr. Li stated. “Earlier compounds destabilized the Ebola entry protein.”

By capturing the molecule bound to its target, researchers gained a molecular view of the binding pocket.

Preclinical Efficacy and Pharmacokinetic Metrics

Metric / Parameter	Experimental Finding	Clinical Significance
Screening Scale	~4.73 billion molecules	Explored vast chemical diversity via DNA-Encoded Chemistry Technology.
Inhibitory Potency (IC50)	0.65 nM against authentic virus	Potent suppression of viral entry.
Oral Bioavailability	69% relative to IV dosing	Indicates potential for oral dosing formulations.
Primary Mechanism	Protein conformation stabilization	Prevents the shape changes required for host cell fusion.

Contraindications & When to Consult a Doctor

Because MWAC-3634 remains in the preclinical phase of drug discovery, there are no approved clinical indications, human dosages, or patient contraindications.

Translational Outlook and Future Regulatory Pathways

The discovery of MWAC-3634 provides a blueprint for designing improved versions of the compound. While the oral bioavailability and efficacy data in animal models provide a foundation, additional development and testing must be successfully completed before this small molecule can be considered for use in people.

Photo: med.umn.edu

References

• Bu, F., et al. (2026). Nature Communications.
• University of Minnesota. (2026).

Disclaimer: This article is for informational and educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations for Ebola virus disease or any other medical condition.