Intranasal type I interferon treatment is beneficial only when administered before clinical signs onset in the SARS-CoV-2 hamster model

Bessiere, P.; Wasniewsk, M.; Picard-Meyer, E.; Servat, A.; Figueroa, T.; Foret-Lucas, C.; Coggon, A.; Lesellier, S.; Boue, F.; Cebron, N.; Gausseres, B.; Trumel, C.; Foucras, G.; Salguero, F. J.; Monchatre-Leroy, E.; Volmer, R.

doi:10.1101/2021.02.09.430458

bioRxiv · 10.1101/2021.02.09.430458

Intranasal type I interferon treatment is beneficial only when administered before clinical signs onset in the SARS-CoV-2 hamster model

Bessiere, P.·Wasniewsk, M.·Picard-Meyer, E.·Servat, A.·Figueroa, T.·Foret-Lucas, C.·Coggon, A.·Lesellier, S.·Boue, F.·Cebron, N.·Gausseres, B.·Trumel, C.·Foucras, G.·Salguero, F. J.·Monchatre-Leroy, E.·Volmer, R.

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Abstract

Impaired type I interferons (IFNs) production or signaling have been associated with severe COVID-19, further promoting the evaluation of recombinant type I IFNs as therapeutics against SARS-CoV-2 infection. In the Syrian hamster model, we show that intranasal administration of IFN- starting one day pre-infection or one day post-infection limited weight loss and decreased viral lung titers. By contrast, intranasal administration of IFN- starting at the onset of symptoms three days post-infection had no impact on the clinical course of SARS-CoV-2 infection. Our results provide evidence that early type I IFN treatments are beneficial, while late interventions are ineffective, although not associated with signs of enhanced disease. One Sentence SummaryThe timing of type I interferon treatment is a critical determinant of its efficacy against SARS-CoV-2 infection.

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Bessiere, P., Wasniewsk, M., Picard-Meyer, E., Servat, A., Figueroa, T., Foret-Lucas, C., Coggon, A., Lesellier, S., Boue, F., Cebron, N., Gausseres, B., Trumel, C., Foucras, G., Salguero, F. J., Monchatre-Leroy, E., Volmer, R.. 2021-02-09. Intranasal type I interferon treatment is beneficial only when administered before clinical signs onset in the SARS-CoV-2 hamster model. https://doi.org/10.1101/2021.02.09.430458

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