Journal: Viruses

Article Title: Molnupiravir and Its Active Form, EIDD-1931, Show Potent Antiviral Activity against Enterovirus Infections In Vitro and In Vivo

doi: 10.3390/v14061142

Figure Lengend Snippet: The molecular formula of EIDD−1931 and EIDD−2801 and the in vitro antiviral effects against EV−A71. ( A ) The molecular formula of EIDD−1931 and EIDD−2801. ( B – G ) The antiviral activities of EIDD−1931 ( B – D ) and EIDD2801 ( E – G ) against EV−A71 in different cells lines. RD cells, Vero cells, and Huh7 cells were infected with the EV−A71 H strain at 100 × TCID 50 . Different doses of the test compounds were then added. At 72 h.p.i, the antiviral parameters were measured. The antiviral effects and cytotoxicity of EIDD−1931 and EIDD−2801 were measured using a CellTiter−Glo cell viability assay kit. The EC 50 and CC 50 were calculated using Origin 9.0 software. SI = CC 50 /IC 50 .

Article Snippet: EIDD-1931(cat no. T8498) and EIDD-2801 (cat no. T8309) powders were purchased from TargetMol (Shanghai, China), and NITD008 (7-Deaza-2′-C-acetylene-adenosine, cat no. HY-12957) powders were purchased from MCE (Shanghai, China).

Techniques: In Vitro, Infection, Viability Assay, Software

Journal: Viruses

Article Title: Molnupiravir and Its Active Form, EIDD-1931, Show Potent Antiviral Activity against Enterovirus Infections In Vitro and In Vivo

doi: 10.3390/v14061142

Figure Lengend Snippet: Antiviral activities of EIDD−1931 and EIDD−2801 against EV−A71 in vitro. ( A – D ) EV−A71 virus particle yields and viral RNA reduction assay. RD cells were infected with EV71 at an MOI of 0.1 PFU/mL in the presence of different concentrations of EIDD−1931 or EIDD−2801. After 30 h, the virus particle yields in the supernatant were measured by TCID 50 . Total cellular RNA was extracted and subjected to qRT−PCR to measure viral RNA expression. All data are shown as means ± standard deviation from three independent experiments. Statistical significance was calculated using one-way ANOVA. * p < 0.05, ** p < 0.01, *** p < 0.001, and **** p < 0.0001. ( E – G ) Inhibitory effects of EIDD-1931 and EIDD−2801 on viral VP1 protein. ( E ) RD cells were infected with EV−A71 at an MOI of 1 PFU/mL in the presence of EIDD−1931 or EIDD−2801. At 16 h.p.i., the cells were fixed for immunofluorescence assays. EV−A71 VP1 proteins were stained using mouse anti−EV−A71 antibody (12D7) (red), and cell nuclei were stained using Hoechst 33,342 (blue), scale bar: 50 µm. ( F , G ) RD cells infected with EV−A71 (MOI = 1) were treated with the test compounds at the indicated concentrations. At 24 h post infection, the cells were collected for Western blot analysis using anti−EV−A71VP1 antibodies (12D7). ( H , I ) Proteins levels of EV−A71 VP1 were quantified by ImageJ software. * p < 0.05, **** p < 0.0001.

Article Snippet: EIDD-1931(cat no. T8498) and EIDD-2801 (cat no. T8309) powders were purchased from TargetMol (Shanghai, China), and NITD008 (7-Deaza-2′-C-acetylene-adenosine, cat no. HY-12957) powders were purchased from MCE (Shanghai, China).

Techniques: In Vitro, Infection, Quantitative RT-PCR, RNA Expression, Standard Deviation, Immunofluorescence, Staining, Western Blot, Software

Journal: Viruses

Article Title: Molnupiravir and Its Active Form, EIDD-1931, Show Potent Antiviral Activity against Enterovirus Infections In Vitro and In Vivo

doi: 10.3390/v14061142

Figure Lengend Snippet: EIDD-1931 and EIDD-2801 exert in vivo antiviral effects against EV-A71 infection. Four groups of 1-day-old ICR suckling mice were i.p. infected with 10 6 PFU of EV-A71 virus (H strain), followed by i.p. treatment with EIDD-1931, EIDD-2801, or vehicle at the indicated dosages for 7 consecutive days. Survival ( A , C ) and body weight ( B , D ) were recorded every day until 21 d.p.i. Data for B and D are presented as means ± standard deviations. Survival data were analyzed with a log-rank test. ** p < 0.01, **** p < 0.0001.

Article Snippet: EIDD-1931(cat no. T8498) and EIDD-2801 (cat no. T8309) powders were purchased from TargetMol (Shanghai, China), and NITD008 (7-Deaza-2′-C-acetylene-adenosine, cat no. HY-12957) powders were purchased from MCE (Shanghai, China).

Techniques: In Vivo, Infection

Journal: Viruses

Article Title: Molnupiravir and Its Active Form, EIDD-1931, Show Potent Antiviral Activity against Enterovirus Infections In Vitro and In Vivo

doi: 10.3390/v14061142

Figure Lengend Snippet: EIDD-1931 and EIDD-2801 reduce the viral loads in various tissues of 1-day-old ICR suckling mice. Three groups of 1-day-old ICR suckling mice were i.p. infected with 10 6 PFU of EV-A71 virus (H strain), followed by i.p. treatment with EIDD-1931 and EIDD-2801 at a dosage of 200 mg/kg for 4 consecutive days. Then, the mice were euthanized, and brain ( A ), heart ( B ), intestine ( C ), liver ( D ), limb muscles ( E ) and lung ( F ) were separately harvested to determine the viral RNA loads using qRT-PCR. Data are presented as means ± standard deviations, and Student’s unpaired t test was performed for statistical analysis. * p < 0.05, ** p < 0.01, *** p < 0.001, and **** p < 0.0001.

Article Snippet: EIDD-1931(cat no. T8498) and EIDD-2801 (cat no. T8309) powders were purchased from TargetMol (Shanghai, China), and NITD008 (7-Deaza-2′-C-acetylene-adenosine, cat no. HY-12957) powders were purchased from MCE (Shanghai, China).

Techniques: Infection, Quantitative RT-PCR

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: Effect of 4′-FlU on survival outcome and body weights of mice treated prophylactically and challenged with RVFV, DBV, or OROV. Animals in each group were treated p.o., QD with the indicated dose of 4′-FlU, placebo, or positive control drug ( n = 10, unless otherwise indicated) initiated within 2 h of each infection. ( A ) BALB/c mice challenged with RVFV, ( B ) Ifnar -/- mice challenged with DBV, and ( C ) Ifnar -/- mice challenged with OROV. The weight data are represented as the group mean and standard error of the percent change in weight of surviving animals relative to their starting weights on the day of virus challenge. Solid symbols in the single-day RVFV weight loss graph represent the same animals in . Sham-infected (MEM only) normal control animals ( n = 4) are shown for comparison. Blue-shaded areas denote the treatment durations. **** P < 0.0001, *** P < 0.001, ** P < 0.01, * P < 0.05 compared with animals that received the placebo.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: Positive Control, Infection, Virus, Control, Comparison

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: Analysis of day 4 viremia and tissue viral titers in virus-infected mice treated with 4′-FlU. Mice were treated prophylactically with 4′-FlU then challenged with ( A ) RVFV, ( B ) DBV, or ( C ) OROV. Subsets of animals in each group ( n = 4-5) were designated for sacrifice on day 4 p.i. to assess infectious virus titers in the serum, liver, and spleen tissues. Unique symbols in each treatment group represent values for the same animal across all parameters. Horizontal lines represent the mean for each group. The dotted lines represent the assays’ lower limits of detection. **** P < 0.0001, *** P < 0.001, ** P < 0.01, * P < 0.05 compared with animals that received the placebo.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: Virus, Infection

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: Effect of delayed 4′-FlU treatment on survival outcome and daily weights of mice challenged with RVFV, DBV, or OROV. Animals in each group ( n = 10, unless otherwise indicated) were treated p.o., QD with the indicated dose of 4′-FlU, placebo, or positive control drug. ( A ) BALB/c mice challenged with RVFV. ( B ) Ifnar -/- mice challenged with DBV. ( C ) Ifnar -/- mice challenged with OROV. The weight data are represented as the group mean and standard error of the percent change in weight of surviving animals relative to their starting weights on the day of virus challenge. Sham-infected (MEM only) normal control animals are shown for comparison. Blue-shaded areas define the treatment (Tx) range, and brackets indicate specific group Tx durations. **** P < 0.0001, *** P < 0.001, ** P < 0.01, * P < 0.05 compared with animals that received the placebo.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: Positive Control, Virus, Infection, Control, Comparison

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: Analysis of viremia and tissue viral titers in virus-challenged mice treated post-exposure with 4′-FlU. Mice were challenged with ( A ) RVFV, ( B ) DBV, or ( C ) OROV, then treated with 4′-FlU beginning on the indicated day p.i. Subsets of animals in each group ( n = 4) were designated for sacrifice on day 3 or 4 p.i. to assess infectious virus titers in the serum, liver, and spleen tissues. Unique symbols in each treatment group represent values for the same animal across all parameters. Horizontal lines represent the mean for each group. The dotted lines represent the assays’ lower limits of detection. **** P < 0.0001, *** P < 0.001, ** P < 0.01, * P < 0.05 compared with animals that received the placebo.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: Virus

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: Impact of 4′-FlU dose sparing on DBV-infected Ifnar -/- mice when treatment is started 4 days p.i. Animals in each group ( n = 10/treatment group; n = 4 sham-infected normal controls) were treated p.o., QD with 10 mg/kg 4′-FlU starting on day 4 p.i., for the indicated number of days to assess ( A ) survival outcome and ( B ) daily body weights. The weight data are represented as the group mean and standard error of the percent change in weight of surviving animals relative to their starting weights on the day of virus challenge. ( C ) Day 5 weight change from all animals. ( D ) viremia, ( E ) liver, and ( F ) spleen tissue viral titers from pre-selected mice in the 7-day treatment and placebo groups sacrificed on day 5 p.i. Samples could not be obtained from 3 mice in the placebo group. Solid symbols shown in panel C represent the same animals sacrificed for viral titer analyses. Horizontal lines represent the mean for each group. The dotted lines represent the assays’ lower limits of detection. **** P < 0.0001, *** P < 0.001, ** P < 0.01, * P < 0.05 compared with animals that received the vehicle placebo.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: Infection, Virus

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: Effect of 4′-FlU treatment administered QOD on Ifnar -/- mice challenged with OROV. Animals in each group ( n = 10/treatment group unless otherwise indicated; n = 4 sham-infected normal controls) were treated p.o., QOD with the indicated dose of 4′-FlU, initiated on day 2 p.i., for 9 days in duration. ( A ) Survival and ( B ) body weights were assessed daily. The weight data are represented as the group mean and standard error of the percent change in weight of surviving animals relative to their starting weights on the day of virus challenge. Sham-infected animals are shown for comparison. ( C ) Day 5 weight change of all animals. Subsets of animals in each group ( n = 3-4) were predesignated for sacrifice on day 4 p.i. to assess ( D ) serum, ( E ) liver, and ( F ) spleen virus titers. They did not receive the second dose of 4′-FlU. Samples could not be collected from a single mouse in the placebo group, which succumbed before it could be euthanized on day 4. Unique symbols in each treatment group represent values for the same animal across all parameters. Horizontal lines represent the mean for each group. The dotted lines represent the assays’ lower limits of detection. **** P < 0.0001, *** P < 0.001, ** P < 0.01, * P < 0.05 compared with animals that received the placebo.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: Infection, Virus, Comparison

Journal: mBio

Article Title: Effective treatment of advanced Oropouche virus, Rift Valley fever virus, and Dabie bandavirus infections with 4'-fluorouridine

doi: 10.1128/mbio.01467-25

Figure Lengend Snippet: In vitro and in vivo comparison of the prototypic BeAn 19991 and 240023 reassortant strains of OROV. ( A ) Growth kinetics of both OROV strains in Vero E6 cells infected at an MOI of 0.001. Cell culture supernatants were collected every 24 h for 6 days, and infectious virus concentrations were determined by endpoint titration in Vero E6 cells. **** P < 0.0001, *** P < 0.001, * P < 0.05. ( B ) Survival and ( C ) body weights were assessed daily in Ifnar -/- mice ( n = 10/treatment group; n = 4 sham-infected normal controls) challenged s.c. with 50 CCID 50 of the indicated strain of OROV and treated p.o., QD with 3 mg/kg 4′-FlU or the vehicle placebo, initiated on day 2 p.i., for 8 days. The body weight data are represented as the group mean and standard error of the percent change in weight of surviving animals relative to their starting weights on the day of virus challenge. Normal control animals ( n = 4) are shown for comparison. **** P < 0.0001 compared with respective placebo-treated animals challenged with the same strain.

Article Snippet: Varying concentrations of 4′-FlU (Emory Institute for Drug Development), ribavirin (ICN Pharmaceuticals, Inc.), or favipiravir (TargetMol) were added to quadruplicate test wells containing 70%–80% confluent Vero 76 (RVFV) or Vero E6 (DBV and OROV) cells just prior to infection at a multiplicity of infection (MOI) of approximately 0.002.

Techniques: In Vitro, In Vivo, Comparison, Infection, Cell Culture, Virus, Titration, Control

Journal: Communications Biology

Article Title: PIKfyve-specific inhibitors restrict replication of multiple coronaviruses in vitro but not in a murine model of COVID-19

doi: 10.1038/s42003-022-03766-2

Figure Lengend Snippet: a Groups of mice were treated intraperitoneally with PIKfyve inhibitors WX8 or NDF once daily beginning 1 day pre-intranasal-challenge with 1 × 10 5 plaque forming units SARS-CoV-2 (B.1.351). EIDD-2801 dosed twice a day was used as a positive treatment control and uninfected treatment controls were included to assess cytotoxicity. Image created using BioRender. b Weight changes were determined for 4 days post-challenge, plotted as the group mean with error bars indicating the ±SD. c Infectious viral loads from lung homogenates at 2 (black) or 4 (gray) days post SARS-CoV-2 challenge. d Lungs were collected at 2- or 4-days post-challenge and stained with hematoxylin and eosin to assess bronchiolar and alveolar damage and immune cell infiltration (500-μm scale bar shown at bottom left, representative for all panels). Mixed-effects analysis was used to compare differences in weight change or viral loads from lung homogenates between infection treatment groups and the vehicle-treated control group; ** p ≤ 0.01, **** p ≤ 0.0001. dpi, days post-infection; PO, oral dosing; IP, intraperitoneal; IN, intranasal.

Article Snippet: EIDD-2801 (150 mg/kg, WuXi AppTec) was dosed orally, twice daily, starting one day prior to infection was used as a positive control for all experiments, as it has been shown to be efficacious in animal models previously , .

Techniques: Staining, Infection

Journal: Communications Biology

Article Title: PIKfyve-specific inhibitors restrict replication of multiple coronaviruses in vitro but not in a murine model of COVID-19

doi: 10.1038/s42003-022-03766-2

Figure Lengend Snippet: a Groups of mice were treated intraperitoneally with PIKfyve inhibitors Apilimod, WX8, or NDF once daily beginning 1 day post-intranasal-challenge with 1 × 10 3 plaque forming units SARS-CoV-2 (MA-10). EIDD-2801 dosed twice a day was used as a positive treatment control and uninfected treatment controls were included to assess cytotoxicity. Image created using Biorender. b Weight changes were determined for 4 days post-challenge, plotted as the group mean with error bars indicating the ±SD. c Infectious viral loads from lung homogenates at 2- (black) or 4- (gray) days post SARS-CoV-2 challenge. d Survival curves for treatment groups. e Lungs were collected at 2- or 4-days post-challenge and stained with hematoxylin and eosin to assess bronchiolar and alveolar damage and immune cell infiltration (500-μm scale bar shown at bottom left, representative for all panels). Mixed-effects analysis was used to compare differences in weight change or viral loads from lung homogenates between infection treatment groups and the vehicle-treated control group; * p ≤ 0.1, *** p ≤ 0.001, **** p ≤ 0.0001. dpi, days post-infection; PO, oral dosing; IP, intraperitoneal; IN, intranasal.

Article Snippet: EIDD-2801 (150 mg/kg, WuXi AppTec) was dosed orally, twice daily, starting one day prior to infection was used as a positive control for all experiments, as it has been shown to be efficacious in animal models previously , .

Techniques: Staining, Infection