Q: Can you explain what is different about COVID-19 that we may so quickly have an effective vaccine if we still don’t have one for HIV/AIDS and other terrible diseases that have been around longer. What makes a vaccine for this virus easier to achieve?
A: Scientists are hopeful because vaccines in development now are leveraging understanding from prior research on coronaviruses.
We also live in an unprecedented time when it is possible to sequence genomes, produce new genomic sequences, and manufacture vaccines quickly. Coronaviruses are easier to target than other viruses such as HIV, the virus that causes AIDS.
Moderna and INOVIO had previously worked on a vaccine for MERS-CoV. The companies leveraged the insights from that viral vaccine research to the new SARS-CoV-2, the virus that causes COVID-19. Research into failed SARS-CoV-1 vaccines also led researchers to design the SARS-CoV-2 vaccine differently. Most vaccines for SARS-CoV-2 are only against small parts of the viral genome specifically targeting the spike protein that allows the virus to enter human cells rather than targeting the full virus.
HIV, the virus that causes AIDS, is a notoriously evasive virus. When HIV replicates itself, it makes a lot of mistakes so the virus evolves over time. Coronaviruses can change over time but much more slowly than HIV. Scientists are moving quickly to get a vaccine in place before SARS-CoV-2 evolves into a different strain. We have learned a lot about HIV vaccines. In fact, Janssen is developing a HIV vaccine. The vaccine they are using for SARS-COV-2 is using the same backbone as the HIV vaccine in development.
Scientists are leveraging research from other vaccine programs as well as from MERS and SARS-CoV-1. Funding from the Department of Defense, the National Institutes of Health and Coalition for Epidemic Preparedness Innovations have given insights for science to build upon prior to the discovery of SARS-CoV2. Advances in genomic sequencing and manufacturing has made it easier to identify and make vaccine candidates more quickly than ever. Yet despite these advances, until the phase 3 trials are over, we will not know if these advances have produced a safe, effective vaccine to prevent COVID-19 in record speed.