LAVR-289, a new acyclo-nucleoside phosphonate having broad-spectrum activity against herpesviruses.

Kappler-Gratias, S.; Quentin-Froignant, C.; Marcheteau, E.; Fernandez, J.; Boutolleau, D.; Garcia, V.; Roy, V.; Agrofoglio, L. A.; Gallardo, F.

doi:10.1101/2025.02.20.639249

bioRxiv · 10.1101/2025.02.20.639249

LAVR-289, a new acyclo-nucleoside phosphonate having broad-spectrum activity against herpesviruses.

Kappler-Gratias, S.·Quentin-Froignant, C.·Marcheteau, E.·Fernandez, J.·Boutolleau, D.·Garcia, V.·Roy, V.·Agrofoglio, L. A.·Gallardo, F.

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Abstract

Human herpesviruses are latent opportunistic large dsDNA viruses that can have deleterious effect in immunocompromised patients by triggering life-threatening infections. Over the past years, different antivirals have been developed against a variety of herpesviruses, including Acyclovir for herpes simplex viruses (HSV1 and 2) and ganciclovir and letermovir for human cytomegalovirus (hCMV). However, broad-spectrum inhibitors of herpesvirus infections are still missing. Here we report the efficacy of LAVR-289, a new acyclic nucleoside analog, on a broad variety of herpesviruses from human and animal origin. LAVR-289 displays nanomolar efficiency in vitro, is active on viral strains resistant to gold standard antivirals and ex vivo on reconstituted human skin infected with HSV1. Combined with its anti-poxvirus and anti-adenovirus activity, LAVR-289 can become the next gold standard for the management of opportunistic virus infections in immunocompromised patient.

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Kappler-Gratias, S., Quentin-Froignant, C., Marcheteau, E., Fernandez, J., Boutolleau, D., Garcia, V., Roy, V., Agrofoglio, L. A., Gallardo, F.. 2025-02-20. LAVR-289, a new acyclo-nucleoside phosphonate having broad-spectrum activity against herpesviruses.. https://doi.org/10.1101/2025.02.20.639249

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