mRNA vaccines are not just for Covid

By Sean J. Ennevor, MD

They may prove useful against other viruses, bacteria, even cancer 

Last week, the World Health Organization announced that the COVID pandemic is no longer an emergency. One would think then that we’d hear less about mRNA (messenger ribonucleic acid) vaccines. These state-of-the-art mRNA vaccine technologies and their speedy implementation were brought into the spotlight during the pandemic. 

Johnson and Johnson created a vector vaccine via an adenovirus to deliver the Sars- Cov- 2 spike protein during the pandemic. Viral vector-based vaccines use a harmless virus to deliver instructions to the body for making antigens from the disease-causing virus into cells, triggering protective immunity against it. This differs from Pfizer and Moderna’s delivery of the spike protein via mRNA-based vaccines. Either delivery can be used to trigger the body’s immune response to combat the virus.  

Interestingly, the same immune response to mRNA vaccines is applicable to other pathogens and diseases. We may use this approach to combat other viruses, bacteria, or even cancer. 

This has been possible as this vaccine technology has actually been around for a long time and is well established. These types of vaccines are also being applied to other problematic conditions, including cancer, influenza, and respiratory syncytial virus, also known as RSV.

Pfizer and Moderna developed the Covid vaccines utilizing their experience with mRNA vaccines. These vaccines were present over a decade prior to the pandemic. Just as mRNA vaccines instruct the body to mount a response to proteins within viruses, it also does the same with proteins within tumor cells when the immune system is instructed to do so via the mRNA programming, in essence creating a vaccine to be applied against cancers.  

Dendritic cells found in the skin, intestines, nose, lungs and GI tract take up the mRNA and then produce proteins and antigens. The production causes the upregulation—the process of increasing the response to a stimulus—of T cells and starts an immune response to attack the tumor. 

While no mRNA cancer vaccine is approved by FDA for treatment of cancer solely or even with long-established chemotherapy, they are approved for use with medications that enhance the body’s immune response to tumors. These medications are known as biologics, and the mRNA vaccines add to the enhanced response of one’s own immune system.

A universal mRNA-based influenza vaccine may be on the horizon. This is significant as millions are infected by flu annually. Of those, hundreds of thousands are hospitalized. Sadly, upwards of 50,000 people die from influenza every year.  

It is a challenging virus to battle as there are at least 20 strains of influenza all prone to seasonal mutation. Making a specific vaccine for each strain is quite challenging as the designers can only try and predict the predominant strain of flu when utilizing non-mRNA vaccine technologies.

The mRNA prototype vaccine will allow scientists to design a vaccine that induces the body to create a protein that is a similar protein in all the various flu mutations. In that way one vaccine could be effective against the variety of flu strains that exist.

Unlike a potential flu mRNA vaccine, Arexvy, a new mRNA vaccine for RSV, is here today.  RSV is similar to measles or mumps in biological form, but many people with RSV infection present mildly as if they have a bad cold. Unfortunately, in young children or the elderly, both of whom may have compromised immune systems, RSV infection may lead to respiratory compromise or even pneumonia requiring hospitalization. 

Some readers may recall the older RSV-inactivated virus vaccine offered to babies in the 1960s. Many children who received that vaccine sadly had worse infections after exposure to the RSV. The new vaccine reportedly will not cause this due to how it works, and it should greatly lower the risk of serious respiratory infection after exposure to RSV.

With all these scientific innovations comes regulation. Safety is paramount, and while mRNA-based vaccines have been deemed safe, proper vetting of these vaccines will require some time. Easily and rapidly made treatment solutions for viruses and bacteria that may make us sick are essential if we are to avoid future pandemics.

Sean J. Ennevor, M.D. graduated with a B.A.S. in biology and economics from Stanford University, and as a Dean’s Scholar from UCLA School of Medicine where he received his MD. He completed his medical residency and fellowship in anesthesiology at Yale University, where he was chief resident and on staff. He practiced medicine in the Twin Cities for over 14 years, and presently serves as an advisor and investor for medical technology companies throughout the country.