EIDD-1931

EIDD-1931 (Beta-d-N4-hydroxycytidine; NHC) is a novel nucleoside analog and behaves as a potent anti-virus agent. EIDD-1931 effectively inhibits the replication activity of venezuelan equine encephalitis virus (VEEV), Chikungunya virus (CHIKV) and hepatitis C virus (HCV)^[1]. In Vitro: Beta-d-N4-hydroxycytidine is an anti-VEEV (venezuelan equine encephalitis virus) agent with EC₅₀, EC₉₀, and EC₉₉ are 0.426, 1.036, and 2.5 μM, respectively^[1].
Beta-d-N4-hydroxycytidine inhibits CHIKV replicon activity and the 50% effective concentration (EC₅₀) s 0.8 μM in the Huh-7-CHIKV replicon cell line. Similar results is presented with the replicon in BHK-21 cells (EC₅₀=1.8 μM)^[2].
NHC has no cytotoxicity for NHC in the Huh-7 cell culture system until up to 100 μM using MTT assays. The 50% cytotoxic concentration (CCsub>50) values for NHC are determined to be 30.6 μM, 7.7 μM, and 2.5 μM in peripheral blood mononuclear (PBM), Vero, and CEM cells, respectively^[2].
NHC behaves as a pyrimidine analog, NHC-mediated inhibition of the CHIKV replicon can be abrogated by the addition of exogenous nucleosides, such as pyrimidines C and U, but dA, dC, dG, dU, or T has no impact on the replicon. Pyrimidines A and G contributes to replicon inhibition both in the presence and in the absence of NHC^[2].