Tafenoquine inhibits replication of SARS-Cov-2 at pharmacologically relevant concentrations in vitro

Geoffrey Dow; Angela Luttick; Jen Fenner; David Wesche; Karen Rowland Yeo; Craid Rayner

doi:10.1101/2020.07.12.199059

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bioRxiv · 10.1101/2020.07.12.199059

Tafenoquine inhibits replication of SARS-Cov-2 at pharmacologically relevant concentrations in vitro

Geoffrey Dow·Angela Luttick·Jen Fenner·David Wesche·Karen Rowland Yeo·Craid Rayner

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Abstract

Tafenoquine [TQ] exhibited EC50/90s of ~ 2.6/5.1 M against SARS-CoV-2 in VERO E6 cells and was 4-fold more potent than hydroxychloroquine [HCQ]. Time-of-addition experiments were consistent with a different mechanism for TQ v HCQ. Physiologically based pharmacokinetic (PBPK) modeling suggested that lung unbound concentrations of TQ in COVID-19 patients may exceed the EC90 for at least 8 weeks after administration. The therapeutic potential for TQ in management of COVID-19 should be further evaluated.

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Geoffrey Dow, Angela Luttick, Jen Fenner, David Wesche, Karen Rowland Yeo, Craid Rayner. 2020-07-12. Tafenoquine inhibits replication of SARS-Cov-2 at pharmacologically relevant concentrations in vitro. https://doi.org/10.1101/2020.07.12.199059

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