Human trials for the first mRNA HIV vaccine will begin this week.

Recently, Moderna, the Massachusetts-based American biotechnology company, indicated to begin human trials for a vaccine for HIV (human immunodeficiency virus) in September.

What is mRNA, and how do mRNA vaccines work?

• Messenger RNA (mRNA)is expected to work similar to the Covid-19 vaccine — by getting the body’s cells to produce the HIV virus’s spike protein triggering an immune response.
• mRNA provides a recipe that human cells can use to make proteins.
• After injection, the cells in arm muscles pick up the mRNA, make the protein, and display it on the cell's surface.
• Human’s immune system sees the protein and learns how to make an immune response against it.

Key-Points

• mRNA-1644 will be the first HIV mRNA vaccine to be trialled in humans. 
• mRNA vaccines tricks the body into producing some of the viral proteins itself.
• They work by using mRNA, or messenger RNA, which is the molecule that essentially puts DNA instructions into action. Inside a cell, mRNA is used as a template to build a protein.
• mRNA-1644, is based on the same mRNA platform as Moderna’s highly effective Covid-19 jab, which is one of two of the only mRNA vaccines to be authorized anywhere in the world. 
• The other is Pfizer-BioNTech’s Covid-19 vaccine.

What are the advantages over other vaccine strategies?

• Safety: Unlike live-attenuated or viral-vectored vaccines, mRNA is non-infectious and poses no concern for DNA integration—mainly because it cannot enter the nucleus, which contains DNA.
• Production: mRNA can be quickly designed and scaled up, if necessary.

Significance

• The quest to develop an HIV vaccine is considered very important for scientific research.
• While treatment with Antiretroviral Therapy has significantly improved the longevity of those with AIDS.
• 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.
• RNA-based immunogens are believed to be a promising alternative because they do not involve the use of a live virus, can be made relatively easily, can be quickly deployed and safely administered.

Challenges

• Of the people living with HIV, over two-thirds are in Africa. Any success in containing the HIV pandemic would mean drastically cutting the rates of transmission there.
• However, as the experience with the Moderna and Pfizer vaccines shows, getting essential jabs to the regions where they are most needed is the biggest stumbling block.
• Another challenge with mRNA vaccines is that they are sensitive to temperature in storage, and is a challenge for developing countries.