Potential repurposing of the HDAC inhibitor valproic acid for patients with COVID-19

There is a need for therapeutic approaches to prevent and mitigate the effects of Coronavirus Disease (2019) (COVID-19). The histone deacetylase (HDAC) inhibitor valproic acid, which has been available for the therapy of epilepsy for many years, is a drug that could be repurposed for patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. This article will review the reasons to consider valproic acid as a potential therapeutic to prevent severe COVID-19. Valproic acid could reduce angiotensin-converting enzyme 2 and transmembrane serine protease 2 expression, required for SARS-CoV-2 viral entry, and modulate the immune cellular and cytokine response to infection, thereby reducing end-organ damage. The combined anti-thrombotic, anti-platelet, and anti-inflammatory effects of valproic acid suggest it could be a promising therapeutic target for COVID-19.