Atea’s AT-587 Demonstrates 30-150× HEV Inhibition, Progressing to Phase 1
Atea’s AT-587 and AT-2490 showed 30-150× greater in vitro potency against HEV than sofosbuvir and ribavirin, with high active-metabolite levels in human liver cells and no toxicity. Atea plans to initiate a Phase 1 clinical program for AT-587 mid-2026 to target chronic HEV infections lacking approved antivirals.
1. Preclinical Potency of AT-587 and AT-2490
In vitro studies at CROI 2026 showed AT-587 and AT-2490 inhibited HEV replication 30-150-fold more potently than sofosbuvir and ribavirin, indicating a significant efficacy improvement over existing off-label treatments.
2. Broad Antiviral Activity and Safety
Both compounds were active against multiple flaviviruses, rubella and chikungunya, generated high levels of active metabolite in human liver cells and exhibited no detectable toxicity in preclinical assays.
3. Phase 1 Clinical Program and Unmet HEV Need
Atea selected AT-587 as its lead HEV candidate and plans to start a Phase 1 clinical trial mid-2026, aiming to fill the gap in approved therapies for immunocompromised patients with chronic HEV genotype 3 and 4 infections.