AT-527(Bemnifosbuvir hemisulfate), a hemisulfate salt of AT-511, a guanosine nucleotide prodrug, is a potent and orally active HCV viral replication inhibitor. AT-527 is highly effective in the control of SARS-CoV-2 (COVID-19) infection in vitro (EC90=0.47 μM). Bemnifosbuvir hemisulfate has pangenotypic antiviral activity[1][2][3].Bemnifosbuvir hemisulfate has pan-genotypic antiviral activities that inhibits HCV genotype 1a (HCV GT1a), HCV GT1b, HCV GT2a, HCV GT3a, HCV GT4a, and HCV GT5a replication with EC50 values of 12.8 nM, 12.5 nM, 9.2 nM, 10.3 nM, 14.7 nM, and 28.5 nM, respectively[1]. In normal human airway epithelial cells, the concentration of Bemnifosbuvir hemisulfate required to inhibit replication of SARS-CoV-2 by EC90 is 0.47 μM, very similar to its EC90 against HCoV-229E, HCoV-OC43 and SARS-CoV in Huh-7 cells[2].When given orally to rats (500 mg/kg) and monkeys (30 mg/kg, 100 mg/kg or 300 mg/kg), Bemnifosbuvir hemisulfate preferentially delivers high levels of AT-9010 in the liver in vivo[1].

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months.
Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour.

[1]. Steven S Good, et al. Preclinical evaluation of AT-527, a novel guanosine nucleotide prodrug with potent, pan-genotypic activity against hepatitis C virus. PLoS One. 2020 Jan 8;15(1):e0227104. [2]. Steven S Good, et al. AT-527, a double prodrug of a guanosine nucleotide analog, is a potent inhibitor of SARS-CoV-2 in vitro and a promising oral antiviral for treatment of COVID-19. Antimicrob Agents Chemother. 2021 Feb 8;AAC.02479-20. [3]. Elina Berliba, et al. Safety, pharmacokinetics and antiviral activity of AT-527, a novel purine nucleotide prodrug, in HCV-infected subjects with and without cirrhosis. Antimicrob Agents Chemother. 2019 Sep 30;63(12):e01201-19.