Trials | Vaccine | 26th August 2021 | Virtual Wire
Moderna company has indicated that it may begin human trials for a vaccine for HIV (human immunodeficiency virus) soon, employing the same mRNA platform that it has used in its COVID-19 vaccine.
The vaccine is a collaboration between Moderna, the International AIDS Vaccine Initiative (IAVI) and the Bill and Melinda Gates Foundation (BMGF). While treatment with Anti-Retroviral Therapy has significantly improved the longevity of those with HIV-AIDS, this is a lifelong treatment.
According to the World Health Organization, there are around 37.7 million living with HIV as of 2020. Traditional vaccine approaches have not worked for HIV, and in fact, some of them have gone on to worsen the infection.
The quest to develop an HIV vaccine is considered among the holy grails of scientific research. Messenger ribonucleic acid (mRNA) plays a vital role in human biology, specifically in a process known as protein synthesis. mRNA is a single-stranded molecule that carries genetic code from DNA in a cell’s nucleus to ribosomes, the cell’s protein-making machinery.
Unlike the traditional pharmaceutical approach which used small molecules or the traditional biologics which used recombinant proteins and monoclonal antibodies for treatment, mRNA medicines are sets of instructions. And these instructions direct cells in the body to make proteins to prevent or fight disease.
The vaccine designated formally as m-RNA-1644 is made in a way to stimulate the B cells of the immune system. The B cells are a class of white blood cells that produce what is referred to as broadly neutralising antibodies (bnAbs).
These antibodies attach to the surface proteins of HIV and disable them by accessing key but hard-to-reach regions on the virus and deactivate them. Using mRNA as a drug opens up a breadth of opportunities to treat and prevent disease. mRNA medicines can go inside cells to direct protein production, something not possible with other drug approaches.
Thus it opens up the immense potential to treat or prevent diseases that today are not addressable – potentially improving human health and impacting lives around the world.
RNA-based immunogens in vaccines do not involve the use of a live virus, can be made relatively easily, can be quickly deployed and safely administered. The instability of mRNA vaccines is a challenge.
A major challenge with m-RNA vaccines is that they are sensitive to temperature in storage, and is a challenge for arranging for the necessary cold chain infrastructure in resource-starved developing countries.
The success of m-RNA COVID vaccines in reducing hospitalisation and mortality has led to confidence in the underlying m-RNA platform and its potential needs to be studied further.