CI

At a glance

ClinicalIndex Comparison Record
Phase 2Active· 40 enrolled
Drug / intervention
Ensitrelvir +1 moredrug
Likely dose
Not stated in record
Structured eligibility isn't available for this trial yet — see the full criteria in the Eligibility tab below.

Standardized by ClinicalIndex from the ClinicalTrials.gov record · verify against the source.

Search/NCT06161688
NCT06161688Phase 2Active

Placebo-Controlled, Randomized Trial of Ensitrelvir (S-217622) for Viral Persistence and Inflammation in People Experiencing Long COVID (PREVAIL-LC)

Timothy Henrich·interventional·Posted Dec 8, 2023·Updated Apr 2, 2026

In Brief

A Phase 2 clinical trial evaluating Ensitrelvir and Placebo for Long COVID and 2 related conditions. Active but no longer recruiting, targeting 40 participants across 1 site.

Detailed Summary

Persistent viral infection with viral reservoirs and detection of circulating spike protein after the initial acute illness is one potential pathogenic mechanism for Long COVID. This mechanism may be susceptible to antiviral therapy that blocks viral replication, which has the potential to alleviate long COVID symptoms. This trial will study the safety and efficacy of Ensitrelvir (S-217622), an antiviral, to treat individuals with Long COVID in an adult population.

Study Details

Study Typeinterventional
Allocation--
Masking--
Primary Purpose--
CountriesUnited States
CollaboratorsShionogi Inc.

Timeline

Phase 2Active
2024202520262027
First PostedDec 8, 2023
Enrollment StartApr 9, 2024
Primary CompletionDec 20, 2024
Study CompletionDec 31, 2026
TodayJul 2, 2026
Enrollment to primary: 8 monthsPosted 2.6 years ago

Interventions

Ensitrelvirdrug

Those randomized to the experimental arm will receive Ensitrelvir, a protease inhibitor, taken orally for 5 days

Placeboother

Matching placebo for Ensitrelvir