17:34 uur 04-01-2023

XAV-19, the anti-SARS-CoV-2 GH-pAb of XENOTHERA best-in-class against all variants including BQ. 1.1


NANTES, France–(BUSINESS WIRE)– In the context of a major resurgence of the COVID epidemic, the French biotech XENOTHERA announces recent data in favor of the strong interest of its glyco-humanized polyclonal antibody (GH-pAb) XAV-19 to treat patients in the initial viral phase of the disease.

Several neutralization assays carried out by XENOTHERA have supplemented data already published (Vanhove et al. 2020, 2021, 2022). XAV-19 exhibits a strong neutralization activity against all omicron variants, including BQ.1.1, the main variant of SARS-CoV-2 in circulation to date. In the meantime, all monoclonal antibodies today marketed lose their activity against this variant. The neutralizing concentration of XAV-19 (IC50) is identical to that measured for all other variants of SARS-CoV-2.

XAV-19 is in clinic since 2020, with more than 700 patients having participated in trials in France, Bulgaria, Spain, Romania, Greece, and Turkey. The biotech has recently released the first results of its phase II/III clinical trial EUROXAV, suspended due to a low enrollment. Preliminary analysis show that XAV-19 tends to improve the recovery rate and to lower the aggravation risk for moderate patients at WHO score 2, within 6 days after symptoms onset. No safety issue has been raised during the trials.

PK data from patients treated with XAV-19 show a trough level ten times higher than the IC50 (Gaborit et al. 2021). In total, one single injection of XAV-19 is likely to neutralize the BQ.1.1 virus or any other variant during the viral phase of the disease.

Considering the current pandemic situation where there is no remaining therapeutic solution for immuno-compromised patients, for whom the administration of anti-COVID antibodies is essential, XAV-19 from XENOTHERA seems to be one of the most promising candidates to address this medical need.

In parallel, the biotech goes on with 3 products in clinic today and an attractive oncology portfolio.

“Today we reiterate our commitment for serving patients and the medical community. While COVID persists as a life-threatening concern, XAV-19 should be considered, in view of its safety and efficacy, particularly on variants, as a viable therapeutic solution for immunocompromised individuals who do not produce their own antibodies. In view of the benefit/risk ratio, we are more than ever ready to move quickly to make XAV-19 available to physicians and patients. In the meantime, we develop further our whole portfolio, particularly in oncology where unmet medical needs are huge also.” comments Odile Duvaux, CEO and co-founder of XENOTHERA.



Founded in 2014, XENOTHERA is a Nantes-based biotech that develops new therapeutic modes in many fields (immunology, oncology, viral infections…). The company develops treatments based on a unique proprietary technology of “glyco-humanized polyclonal antibodies (GH-pAb)”. Its technological platform is built on a dual expertise in genetics and immunology.

The biotech has a complete portfolio of products, including three products in clinic: LIS1, an immunosuppressant for solid organ transplantation; XAV-19, an anti-Covid treatment for patients with moderate disease; and XAB05, for the prevention and treatment of multi-drug resistant bacterial infections.

XENOTHERA, is part of the scientific and medical environment of the Pays de la Loire (France). The company has raised 43M€ since its creation, its main investors are the Pays de la Loire Region, BPI France and the European EIC Fund.

More information: www.xenothera.com

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