iScience
. 2025 Mar 1;28(4):112140.
doi: 10.1016/j.isci.2025.112140. eCollection 2025 Apr 18. 3-Deazaguanosine inhibits SARS-CoV-2 viral replication and reduces the risk of COVID-19 pneumonia in hamster
Noriko Saito-Tarashima 1 , Takaaki Koma 2 3 , Naoto Hinotani 1 , Keigo Yoshida 1 , Moka Ogasa 1 , Akiho Murai 1 , Syuya Inoue 1 , Tomoyuki Kondo 2 , Naoya Doi 2 , Koichi Tsuneyama 3 4 , Masako Nomaguchi 2 3 , Noriaki Minakawa 1
Affiliations
The COVID-19 pandemic highlighted the serious threat that coronaviruses have on public health. Because coronavirus continuously undergoes cross-species transmission, additional therapeutic agents and targets are urgently needed. Here, we show that a 3-deazapurine ribonucleoside, 3-Deazaguanosine (C3Guo, 2), has potent antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Unexpectedly, C3Guo (2) does not act as an inhibitor of RNA-dependent RNA polymerase (RdRp), which is the therapeutic target of two key nucleoside/nucleotide inhibitors approved for the treatment of COVID-19 (Remdesivir and Molnupiravir); instead, it seems to function by targeting the capping machinery of viral RNA. In hamsters infected with SARS-CoV-2, administration of 2 markedly reduced infectious viral titers, and prevented the development of COVID-19 pneumonia better than Molnupiravir. The potency of 2 against SARS-CoV-2 underscores its potential as an effective therapeutic agent for COVID-19 and future zoonotic coronavirus infections and raises the possibility of antiviral nucleoside analogs with alternative therapeutic targets to RdRp.
Keywords: Biological sciences; Health sciences; Immunology.
. 2025 Mar 1;28(4):112140.
doi: 10.1016/j.isci.2025.112140. eCollection 2025 Apr 18. 3-Deazaguanosine inhibits SARS-CoV-2 viral replication and reduces the risk of COVID-19 pneumonia in hamster
Noriko Saito-Tarashima 1 , Takaaki Koma 2 3 , Naoto Hinotani 1 , Keigo Yoshida 1 , Moka Ogasa 1 , Akiho Murai 1 , Syuya Inoue 1 , Tomoyuki Kondo 2 , Naoya Doi 2 , Koichi Tsuneyama 3 4 , Masako Nomaguchi 2 3 , Noriaki Minakawa 1
Affiliations
- PMID: 40171487
- PMCID: PMC11960675
- DOI: 10.1016/j.isci.2025.112140
The COVID-19 pandemic highlighted the serious threat that coronaviruses have on public health. Because coronavirus continuously undergoes cross-species transmission, additional therapeutic agents and targets are urgently needed. Here, we show that a 3-deazapurine ribonucleoside, 3-Deazaguanosine (C3Guo, 2), has potent antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Unexpectedly, C3Guo (2) does not act as an inhibitor of RNA-dependent RNA polymerase (RdRp), which is the therapeutic target of two key nucleoside/nucleotide inhibitors approved for the treatment of COVID-19 (Remdesivir and Molnupiravir); instead, it seems to function by targeting the capping machinery of viral RNA. In hamsters infected with SARS-CoV-2, administration of 2 markedly reduced infectious viral titers, and prevented the development of COVID-19 pneumonia better than Molnupiravir. The potency of 2 against SARS-CoV-2 underscores its potential as an effective therapeutic agent for COVID-19 and future zoonotic coronavirus infections and raises the possibility of antiviral nucleoside analogs with alternative therapeutic targets to RdRp.
Keywords: Biological sciences; Health sciences; Immunology.