GS-704277 is an intermediate alanine metabolite of the antiviral prodrug remdesivir .1,2 It is formed from remdesivir via intracellular hydrolysis. GS-704277 is further metabolized to the nucleoside monophosphate form and then to the nucleoside analog GS-441524 or active nucleoside triphosphate GS-443902.
1.Humeniuk, R., Mathias, A., Cao, H., et al.Safety, tolerability, and pharmacokinetics of remdesivir, an antiviral for treatment of COVID-19, in healthy subjectsClin. Transl. Sci.13(5)896-906(2020) 2.Eastman, R.T., Roth, J.S., Brimacombe, K.R., et al.Remdesivir: A review of its discovery and development leading to emergency use authorization for treatment of COVID-19ACS Cent. Sci.6(5)672-683(2020)