Efficacy of the oral nucleoside prodrug GS-5245 (Obeldesivir) against SARS-CoV-2 and coronaviruses with pandemic potential

Figures

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  Fig. 1.. GS-5245 is broadly active against enzootic, endemic and pandemic coronaviruses in primary human airway cells (A) The mean percent inhibition and cytotoxicity of SARS-CoV-2 replication by GS-5245 and control compounds GS-441524, remdesivir, and PF-07321332 in A459-hACE2 cells is shown (triplicate samples were analyzed). Data is representative of two independent experiments. (B) Antiviral activity of GS-5245 in primary human airway epithelial cell donor 1 against SARS-CoV and related bat-CoV SHC014, SARS-CoV-2 WA1 and SARS-CoV-2 Omicron BA.1 and MERS-CoV. Human airway epithelial cell cultures (HAE) were treated with different doses of drug or DMSO and then infected with SARS-CoV-2 at an MOI of 0.5. After 2 hours of infection, input virus was removed, cultures were washed once, and infectious virus titers in plaque forming units (PFU) was measured in apical washes after 72 hours. Cultures remained in the presence of drug for the duration of the study. (C) Antiviral activity of GS-5245 in primary human airway epithelial cell donor 2 against SARS-CoV and related bat-CoV SHC014, SARS-CoV-2 WA1, and SARS-CoV-2 Omicron BA.1 and MERS-CoV. This was performed similarly but independent of…

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  Fig. 2.. Dose-dependent therapeutic efficacy of GS-5245 against SARS-CoV-2 MA10 in BALB/c mice (A) Percent starting weight through 4 dpi in 10-week-old female BALB/c mice infected with SARS-CoV-2 MA10 at 1 x 104 PFU. Mice were treated BID with vehicle (veh: gray squares), 3 mg/kg GS-5245 (upside-down red triangles), 10 mg/kg GS-5245 (right-side-up blue triangles), 30 mg/kg GS-5245 (green circles), and 100 mg/kg molnupiravir (purple diamonds) starting at 12 hpi. N=10 mice per group. Rx = drug. Asterisks denote p values from a two-way ANOVA after a Dunnett’s multiple comparisons test. * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, **** p ≤ 0.0001 (B) SARS-CoV-2 MA10 lung infectious viral titers 4 dpi in mice treated with vehicle or GS-5245 at increasing concentrations and 100 mg/kg molnupiravir (Mol.). Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (C) Macroscopic lung discoloration at 4 dpi in therapeutically treated mice compared to vehicle. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (D) Pulmonary function (PenH) monitored by whole-body plethysmography from day zero through 4 dpi in…

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  Fig. 3.. Therapeutic efficacy of GS-5245 against pre-emergent bat SARS-related RsSHC014-CoV in K18-hACE2 mice (A) Percent starting weight in 10-week-old female K18-hACE2 mice infected with 1 x 104 PFU therapeutically treated BID with vehicle (veh: gray squares), 10 mg/kg GS-5245 (right-side-up light blue triangles), 30 mg/kg GS-5245 (dark green circles) at 12 hpi, and 10 mg/kg GS-5245 (right-side-up dark blue triangles), and 30 mg/kg GS-5245 (light green circles) at 24 hpi. N=10 mice per group. Asterisks denote p values from a two-way ANOVA after a Dunnett’s multiple comparisons test. (B) RsSHC014-CoV lung infectious viral titers 4 dpi in mice treated with vehicle or GS-5245 at 10 and 30 mg/kg at either 12 or 24 hpi. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (C) Macroscopic lung discoloration at 4 dpi in therapeutically treated K18-hACE2 mice compared to vehicle. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (D) Microscopic ATS acute lung injury pathology scoring at day 4 post infection in vehicle vs. GS-5245-treated mice. Asterisks denote p values from a Kruskal-Wallis test after a…

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  Fig. 4.. GS-5245 protects against SARS-CoV MA15 mortality in BALB/c mice (A) Percent starting weight in 10-week-old female BALB/c mice infected with 1 x 104 PFU therapeutically treated BID with vehicle (veh: gray squares), 10 mg/kg GS-5245 (right-side-up light blue triangles), 30 mg/kg GS-5245 (dark green circles) at 12 hpi, and 10 mg/kg GS-5245 (right-side-up dark blue triangles), and 30 mg/kg GS-5245 (light green circles) at 24 hpi. N=10 mice per group. Asterisks denote p values from a two-way ANOVA after a Dunnett’s multiple comparisons test. (B) SARS-CoV MA15 lung infectious viral titers 4 dpi in mice treated with vehicle or GS-5245 at 10 and 30 mg/kg at either 12 or 24 hpi. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (C) Macroscopic lung discoloration at 4 dpi in therapeutically treated BALB/c mice compared to vehicle. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (D) Percent survival in vehicle vs GS-5245-treated mice. Asterisks denote p values from a Log-rank Mantel-Cox test. (E) Microscopic ATS acute lung injury pathology scoring at 4 dpi in vehicle vs. GS-5245-treated mice.…

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  Fig. 5.. GS-5245 inhibits MERS-CoV disease in 288/330++ DPP4-modified mice (A) Percent starting weight in 20-week-old male and female 288/330++ DPP4-modified mice infected with a mouse-adapted MERS-CoV with 5 x 104 PFU. Mice were therapeutically treated BID starting at 12 hpi with vehicle (veh: gray squares), 10 mg/kg GS-5245 (right-side-up light blue triangles), 30 mg/kg GS-5245 (dark green circles). N=8 total mice per group. Male and female mice were distributed as equally as possible in each group. Asterisks denote p values from a two-way ANOVA after a Dunnett’s multiple comparisons test. (B) MERS-CoV lung infectious viral titers 5 dpi in mice treated with vehicle or GS-5245 at 10 and 30 mg/kg at 12 hpi. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (C) Macroscopic lung discoloration at 5 dpi in therapeutically treated mice compared to vehicle. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (D) Pulmonary function monitored by whole-body plethysmography from day zero through 5 dpi in MERS-CoV-infected treated 288/330++ DPP4 mice. Asterisks denote p values from a two-way ANOVA after a…

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  Fig. 6.. Therapeutic efficacy of GS-5245 against the highly transmissible and neutralization-resistant BA.1 (Omicron B.1.1.529) variant in K18-hACE2 mice (A) Percent starting weight in 10-week-old female K18-hACE2 mice infected at 1 x 104 PFU with a BA.1 clinical isolate. Mice were therapeutically treated BID starting at 12 hpi with vehicle (veh: gray squares) and 30 mg/kg GS-5245 (dark green circles). N=10 mice per group. Asterisks denote p values from a two-way ANOVA after a Dunnett’s multiple comparisons test. (B) BA.1 lung infectious viral titers 2, 3, and 4 dpi in mice treated with vehicle or GS-5245 and 30 mg/kg at 12 hpi. Asterisks denote p values from a Kruskal-Wallis test after a Dunnett’s multiple comparisons test. (C) Macroscopic lung discoloration at 4 dpi in therapeutically treated mice compared to vehicle. Asterisks denote p values from a Mann-Whitney test. (D) Microscopic ATS acute lung injury pathology scoring at 4 dpi in vehicle vs. GS-5245-treated mice. Asterisks denote p values from a Mann-Whitney test. (E) Microscopic DAD acute lung injury pathology scoring at 4 dpi in vehicle vs. GS-5245-treated mice. Asterisks denote p values from a Mann-Whitney test.

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  Fig. 7.. The effect of GS-5245 and PF-332 combination therapy on SARS-CoV-2 MA10 pathogenesis in BALB/c mice (A) Percent starting weight in 10-week-old female BALB/c mice infected at 1 x 104 PFU with a SARS-CoV-2 MA10. Mice were treated BID starting at 12 hpi with vehicle (veh: gray squares) 400 mg/kg PF-332 (purple diamonds), 120 mg/kg PF-332 (light green diamonds), 40 mg/kg PF-332 (blue diamonds), 12 mg/kg PF-332 (dark green diamonds), and 1.2 mg/kg GS-5245 (upside-down red triangles). N=10 mice per group. Asterisks denote p values from a two-way ANOVA after a Dunnett’s multiple comparisons test. (B) SARS-CoV-2 MA10 lung infectious viral titers 4 dpi in mice treated at 12 hpi with vehicle and at decreasing doses of PF-332 and a sub-protective dose of 1.2 mg/kg GS-5245. Asterisks denote p values from a Kruskal-Wallis test with a Dwass-Steel-Critchlow-Fligner procedure for pairwise comparisons. (C) Macroscopic lung discoloration at 4 dpi in therapeutically treated mice compared to vehicle. Asterisks denote p values from a Kruskal-Wallis test with a Dwass-Steel-Critchlow-Fligner procedure for pairwise comparisons. (D) Pulmonary function as measured by whole-body plethysmography in…