New Variant in France Highlights the Challenge for Current Vaccines

April 1, 2021

DEL MAR, California – April 1, 2021 – French virologists in hospital Henri Mondor near Paris reported this week a new variant of the SARS-CoV-2 clade 19B termed HMN.19B and defined by 18 mutations and 2 deletions in the Spike protein. Remarkably, this variant harbors the mutation N501Y of the UK variant B.1.1.7, but also the mutation L452R of the recent California variant CAL.20C.

The emergence of the same mutation 5,600 miles (9,000 kilometers) apart indicates that the same selection pressure is at work worldwide. Scientists discovered the new French variant in an immunocompromised patient, who became infected by the virus while receiving a treatment for inflammatory back pain.

This new French variant is only the most recent case of a number of variants that harbor mutations in all three main variable domains of the Spike protein simultaneously. Other triple domain variants are the UK variant B.1.1.7 and the New York variant B.1.526. All the currently approved vaccines based on the Spike protein face the issue of loss of efficacy against these variants with more than 30 different mutations in three different domains. These mutations represent a combination of more than a billion different Spike antigens to be considered for any future version of these vaccines.

“The diversity of mutations in the Spike protein is staggering, but fortunately we observe a convergence of mutations in the receptor binding domain, and this confirms this domain as the key antigen of second generation vaccines”, according to Pascal Brandys, co-founder and CEO of Phylex BioSciences who is currently developing a second generation multivalent mRNA SARS-CoV-2 vaccine.

“Our antigen derived from this domain, small but very immunogenic, is subject to very few mutations, and consequently allows the design of a multivalent vaccine against all possible variants of concern”.

Brandys also said that other proteins of SARS-CoV-2, such as the Nucleocapsid, are not a good option either as they are also subject to many mutations and do not elicit the neutralizing antibodies that are essential to prevent the virus entry into the host cell.

About Phylex BioSciences

Founded at the beginning of the SARS-CoV-2 pandemic by genomics pioneer Pascal Brandys and coronavirus specialist Jens Herold, Phylex BioSciences is the first company to pursue the development of a multivalent mRNA vaccine against SARS-CoV-2. The vaccine is intended to protect against all variants of concern in the foreseeable future.

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