Adjunct Dexamethasone in Herpes Simplex Encephalitis: Safe but Fails to Improve Long-Term Verbal Memory in the DexEnceph Trial

Core Highlights

The DexEnceph trial provides critical evidence regarding the use of corticosteroids in the management of Herpes Simplex Virus (HSV) encephalitis. The key takeaways from this multicentre, randomised, phase 3 trial include:

• Adjunct dexamethasone did not significantly improve verbal memory scores at 26 weeks compared to aciclovir alone.
• The safety profile of dexamethasone in this population was satisfactory, with no significant difference in serious adverse events between the treatment and control groups.
• The median time to initiate dexamethasone was 7 days after hospital admission, which may have limited its potential impact on early inflammatory damage.
• Early use of corticosteroids in suspected encephalitis appears unlikely to be harmful, supporting their use in cases where other inflammatory aetiologies are suspected alongside HSV.