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Coadministration of #ribavirin and #arenaviral entry #inhibitor LHF-535 enhances antiviral benefit against authentic #Lassa virus

{Excerpt}

Highlights

• A new strain of Lassa virus (LASV) was successfully isolated and characterized.

• The combination of ribavirin and LHF-535 has been demonstrated to exhibit synergistic effects in inhibiting LASV.

• The findings provide new directions for the development of antiviral drugs and vaccines for Lassa fever.


Dear Editor,

Lassa virus (LASV) is the causative agent of the acute viral hemorrhagic Lassa fever (LF), which is classified into Mammarenavirus within the Arenaviridae family, with a single-stranded, negative-sense, bi-segmented RNA genome. Due to its high pathogenicity and lethality, LASV is considered as a priority threat to public health, with an estimated cases of 300,000 infections and 5,000 deaths annually. LASV was first isolated and described as a clinical entity in 1969 in Lassa, Nigeria (Garry, 2023). LASV isolates of different geographic and host origins are highly diverse in genomic sequences and phylogenetically classified into up to seven lineages, with each lineage predominately localized in specific countries. Although the research on LF has been carried out for decades since the pathogen first characterized, there is no approved antiviral drugs or vaccines for clinical use against LASV to date (Grant et al., 2023). One possible reason that hindered the development of countermeasures is that the preclinical studies on authentic LASV are restricted in high bio-containment biosafety level 4 (BSL-4) facilities. In this letter, we describe isolation, and characterization of the LASV from the clinical samples. And we applied a coadministration assay of antiviral drugs for LASV by using a clinically isolated Mammarenavirus lassaense strain in the BSL-4 facility, aiming to investigate new therapeutic strategies for LASV infection.

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Source: Virologica Sinica, https://www.sciencedirect.com/science/article/pii/S1995820X25000380?via%3Dihub

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