Infectious disease

Cell culture and mouse studies suggest the nucleotide analog GS-5734 could help treat or prevent severe acute respiratory syndrome (SARS), Middle East respiratory syndrome coronavirus (MERS-CoV) and coronavirus NL63 infections. In a MERS-CoV-infected human lung epithelial cell line, GS-5734 inhibited viral replication with an IC₅₀ of 25 nM. In primary human airway epithelial cells infected with SARS-CoV or MERS-CoV, GS-5734 inhibited SARS-CoV and MERS-CoV replication with IC₅₀ values of 69 nM and 74 nM, respectively. In the human airway cells infected with human coronavirus NL63, GS-5734 decreased viral replication compared with no treatment. In a mouse challenge model of SARS-CoV infection, subcutaneous injection of GS-5734 before or after challenge decreased weight loss and viral load in the lung and increased lung function compared with vehicle. Next steps could include clinical testing of GS-5734 in coronaviral infections...