The search to stop the spread of the coronavirus pandemic has researchers across the globe racing to develop a vaccine, with more than 100 vaccines currently in development and eight under clinical investigation.
On Monday CNN reported promising early results from studies of a genetic vaccine for
COVID-19. The vaccine was developed by Massachusetts-based Moderna Therapeutics in partnership with the U.S. National Institutes of Health, which led the Phase I trial.
If approved, the vaccine would be the first for COVID-19 and the first genetic vaccine approved and mass produced for use in humans.
A Moderna executive told CNN the vaccine could be available as early as January. However, whether a genetic vaccine can be mass produced remains to be seen, according to Scientific American.
Eight out of 45 trial volunteers were found to have antibody levels that met or surpassed the levels seen in persons who recovered naturally from COVID-19. Antibodies bind to the virus and render it incapable of attacking human cells.
Speeding Things Along
According to CNN, the U.S. Food and Drug Administration has approved the start of Phase II clinical trials which typically involve thousands of study participants before moving onto Phase III trials, which typically involves tens of thousands. However, in light of the urgency of the current situation, the FDA has indicated a willingness to speed things up.
“This is a different time,” Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia and physician in CHOP’s Division of Infectious Diseases, is a member of the NIH panel that’s setting a framework for vaccine studies in the U.S., told CNN.
Traditional vs. Genetic Vaccines
Vaccines work by triggering the body’s immune system to generate a protective response against future infection. All things have antigens or can act as antigens, which helps the immune system identify them. For instance, a toxic molecule would just be an antigen itself. But larger more complex things like cells or bits of cells have molecules stuck on them that are antigens.
If the antigen is foreign, as is the case with a virus, the immune system is activated to attack it and will remember the antigen if it encounters it in the future. Vaccines utilize this process to prepare the body to win against future infections.
Traditional vaccines involve either an injection of a live pathogen that has been weakened or an inactive or dead pathogen. Neither will cause actual disease in patients.
Traditional vaccine development involves growing weakened viruses in cells derived from chicken eggs, which can require four to six months for known viruses. In the case of new diseases, the process can take years.
Developing genetic vaccines for new viruses, on the other hand, could possibly proceed more quickly. Genetic vaccines use injected DNA or RNA to stimulate the production of antigens in the human body itself. (Essential to life and found in every cell, DNA, known as the “double helix” for its double strands, and RNA, which is single-stranded, are molecules that work together to store and read our genetic information to produce the molecules that make us.)
This is in contrast to traditional vaccines which inject altered pathogens that already have antigens on them. Genetic vaccines skip the need for pathogens. Both kinds of vaccines have the same end result, with the immune system recognizing the foreign antigens and creating antibodies for future protection.
Genetic vaccines are generally considered more advantageous than traditional vaccines in part because they give rise to a broader range of immune responses.
Genetic Vaccines Raise Privacy Concerns
Despite their potential advantages, genetic vaccines pose some serious privacy concerns, as discussed in Scientific American.
Genetic testing to obtain personal genetic information from individuals could be helpful in developing targeted therapies as would the sharing of such information between research groups. But codes of ethical conduct and handling policies must also be developed to safeguard personal genetic data and prevent it from being used to penalize or discriminate against individuals or from being exploited by others for financial gain.
Originally published May 22, 2020
By Joanna Shawn Brigid O’Leary
Joanna Shawn Brigid “Bridey” O’Leary was born in Alexandria, Virginia, grew up in central Pennsylvania and Massachusetts, and now calls Houston, Texas home. She graduated from Harvard University with a degree in English and pre-medical studies and earned a PhD in Victorian literature from Rice University. Bridey has served as a medical writer, culinary historian, and travel/food critic for media outlets and academic publications such as Neurosurgery, Let’s Go travel guides, Stroke, Wine Enthusiast, the Onion, Houston Press, Texas Highways, Houstonia, ColinCowie Weddings, and Fit, Strong & Sexy.
Medically Reviewed by Benjamin Duong