Company: RVRC
Filing Date: 2025-10-03
Form Type: S-1/A
Source: 0001213900-25-096094
Chunk: 109

Company: Revium Rx.
Filing Date: 2025-10-03
Form: S-1/A
Chunk 109
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 respective protein, and the resultant antisera neutralises the virus, shows that a vaccination targeting the S protein domain
could be successful in preventing Coronavirus. The S protein of full-length i.e., S1, S2 subunit and RBD, proteins were identified as
critical epitopes for generating neutralising antibodies as per computational analyses and studies on the viruses, SARS-CoV and MERS-CoV
(Middle East Respiratory Syndrome-CoV). Antibodies against the RBD domain have early been shown protection against SARS and MERS-CoV
infections, and the S1 epitope, containing both the RBD as well as N-terminal binding domain, NTD, has also been used to develop vaccines.
A cluster of T cell epitope was discovered in the transmembrane part of the M protein, allowing the development of a significant cellular
type of immune response against the SARS-CoV. For instance, Novavax Inc. (Gaithersburg, Maryland) used Matrix-M combination therapy recombinant
protein nanoparticle technology and the Sf9 system to develop the subunit vaccine candidate for SARS-CoV-2. The antigen in Clover Biopharmaceuticals
Inc.‘s (Shanghai, CN) S-Trimer vaccine is a recombinantly generated homotrimer of the full-length S-protein.

A protein subunit vaccine, also known as a combination
therapy recombinant vaccine, is assembled of virus components that enhance the human immune system without incorporating virus particles
into the body. In 2020, Russian Federation established recombinant adenovirus vectors of type 26 (rAd26) and type 5 (rAd5), both of which
carry the SARS-CoV-2 Spike protein gene. This vaccine was also shown to induce a strong cellular and humoral immune response.

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Other protein-based vaccines consist of virus-like
particles (VLPs), the recombinant proteins or supramolecular structures which may contain one or more copies of 10–200 nm nanoparticles
assembling viral proteins. Virus-like particles are created using structural proteins that have been recombinantly generated (VLPs).
VLPs, the S protein of SARS-CoV-2, facilitate host cell fusion via ACE2 receptor binding and priming via TMPRSS2, unlike in subunit vaccines
where VLPs seem to be unable to directly attach to B cell receptors to form the antibodies. The