Repurposing carrimycin as an antiviral agent against human coronaviruses, including the currently pandemic SARS-CoV-2

COVID-19 pandemic caused by SARS-CoV-2 infection severely threatens global health and economic development. No effective antiviral drug is currently available to treat COVID-19 and any other human coronavirus infections. We report herein that a macrolide antibiotic, carrimycin, potently inhibited the cytopathic effects (CPE) and reduced the levels of viral protein and RNA in multiple cell types infected by human coronavirus 229E, OC43, and SARS-CoV-2. Time-of-addition and pseudotype virus infection studies indicated that carrimycin inhibited one or multiple post-entry replication events of human coronavirus infection. In support of this notion, metabolic labelling studies showed that carrimycin significantly inhibited the synthesis of viral RNA. Our studies thus strongly suggest that carrimycin is an antiviral agent against a broad-spectrum of human coronaviruses and its therapeutic efficacy to COVID-19 is currently under clinical investigation.

Synthesis and antiviral activity of some novel indole-2-carboxylate derivatives

A series of novel indole-2-carboxylate derivatives were synthesized and assayed to determine their in vitro broad-spectrum antiviral activities. The biological results showed that some of the synthesized compounds exhibited potent broad-spectrum antiviral activity. Notably, compound 8f showed the highest SI value (17.1) to Cox B3 virus. Compound 14f showed both potent inhibitory activity against influenza A (IC50=7.53 μmol/L) and the highest SI value (12.1). SAR results showed that the alkyloxy at the 4-position of indole ring was not crucial to the antiviral activities. Incorporation of an acetyl substituent at the amino group disfavored antiviral activity towards RNA viruses.

In vitro and in vivo anti-influenza virus activity of ribavirin injection / 药学学报

Ribavirin is a broad-spectrum inhibitor against several unrelated DNA or RNA viruses in vitro and in vivo. In this paper the in vitro and in vivo study of anti-influenza virus activity of ribavirin (RBV) injection had been reported. The in vitro antiviral activity of ribavirin injection against influenza virus A and B was studied by CPE. The in vivo protective action of ribavirin injection against influenza A/FM/1/47(H1N1) mouse adapted strain infected mouse was studied with mouse model. The results showed ribavirin injection has strong inhibitory activity against 7 virus strains tested in vitro. Ribavirin injection could significantly increase virus infected mouse survival rate and survival days and improve lung pathogen and lung index.

In vitro anti-influenza virus activity of 10 traditional Chinese medicines / 药学学报

Influenza virus is a virus causing upper respiratory tract infection disease with high morbidity and mortality. China is considered as an area with high rate of influenza morbidity. Prevention and treatment of influenza currently rely on vaccines and antiviral agents in the world. In addition, traditional Chinese medicines also have been used in clinical for influenza therapy. In vitro anti-influenza virus activities of 10 traditional Chinese medicines were studied by cytopathic effect (CPE). Qingre Jiedu oral liquid (factory H) had strong antiviral activity against influenza virus A/Guangdong Luohu/219/2006 (H1N1); Yinhuang oral liquid had strong antiviral activity against influenza virus A/Hanfang/359/95 and A/Yuefang/243/72 (H3N2). Qingkailing oral liquid (factory G) had strong antiviral activity against influenza virus A/Jifang/15/90 (H3N2). Qingre Jiedu oral liquid (factory H) had strong antiviral activity against influenza virus A/Jifang/15/90, A/Yuefang/243/72 (H3N2) and virus B.