With the rise in COVID-19 cases this winter during this global pandemic, Pfizer (a pharmaceutical company based in New York) and BioNTech (a biotechnology company based in Germany) provided hopeful news that their vaccine was over 90% effective at preventing COVID-19 on November 9. One week later on November 16, Moderna (a biotechnology company based in Massachusetts) announced that its vaccine candidate was 94.5% effective based on its phase III results of its clinical trial.
Moderna Vaccine Phase III trial results
Among 30,000 participants ages 18 and older in the United States, Moderna reported 95 participants with confirmed cases of COVID-19: 90 cases in the placebo group versus 5 cases in the vaccine group. This study included more than 7,000 people over the age of 65; more than 5,000 people under the age of 65 with high-risk chronic diseases like diabetes, cardiac disease, and severe obesity (42% of the total participants in this trial); and more than 11,000 people from communities of color (37% of the total participants in this trial). The vaccine was generally well tolerated with mild or moderate side effects including fatigue, muscle aches, joint pain, headache, and pain and redness at the injection site (2.0%). Based on these results, the vaccine had a statistically significant efficacy of 94.5%. (1)
How does the vaccine work
Similar to Pfizer’s vaccine, Moderna’s vaccine contains messenger RNA (mRNA), a small portion of the virus’s genetic code that instructs cells to generate the spike protein found on the surface of the coronavirus. As a result, the immune system is able to recognize and respond to the virus if the individual becomes infected in the future. (2)
What are the differences between the Pfizer Vaccine and the Moderna Vaccine?
- Pfizer vaccine needs to be stored in -70о C vs Moderna vaccine at -20оC. Facilities need to have a speciality freezer in order to store the pfizer vaccine, whereas Moderna can be stored in a typical freezer condition and easier to distribute to pharmacies and rural areas.
- Pfizer trial reports vaccine to be >90% effective vs moderna trial shows theirs to be 95% effective
- Both require two doses. Pfizer’s booster shot will be given three weeks after the first one vs Moderna’s is spaced four weeks later
We still are not sure how long the immunity to the coronavirus lasts after an infection or a vaccination. The Centers for Disease Control and Prevention organization also has not evaluated how the vaccine performed on those previously infected, so there is no recommendation if they should be given the vaccine.
Given the promising preliminary data with the mRNA vaccine, Moderna plans to request an Emergency Use Authorization from the Food and Drug Administration as well as regulatory agencies around the world in a matter of weeks. Roughly 20 million doses of the vaccine are expected to be ready for distribution in the United States by the end of this year with another 500 million to 1 billion doses ready for global distribution next year.