As coronavirus cases surge in Champaign County, throughout downstate Illinois and elsewhere, with little relief in sight, we finally got some good news yesterday (November 9th).
First, Pfizer and its partner, the German company, BioNTech, announced preliminary results of its Phase 3 vaccine trial study. Pfizer’s analysis of 43,538 enrolled study participants that suggested their BNT162b2 vaccine was more than 90% effective in preventing COVID-19.
Second, the Food and Drug Administration (FDA) approved emergency use of Eli Lilly’s monoclonal antibody drug to help the immune system fight COVID-19 monoclonal antibodies. The drugs are laboratory-made versions of antibodies – blood proteins which the body creates to help target and eradiate foreign infections. The new therapies are concentrated versions of the antibodies that proved most effective against the virus in patient studies.
Previously, Regeneron’s monoclonal antibody treatment had requested emergency authorization for their antibody drug in late October 2020. Regeneron’s Covid-19 outpatient trial prospectively demonstrates that the REGN-COV2 antibody cocktail significantly reduced virus levels and need for further medical attention These are one-dose treatments through an IV. Early results suggest it may help clear the coronavirus sooner and possibly cut hospitalizations in people with mild to moderate COVID-19. Unfortunately, a study of it in hospitalized patients was stopped when research showed that the drug did not seem to be helping in that situation.
REGN-COV2 antibody cocktail is the drug that President Trump received on October 1st along with the antiviral remdesivir and dexamethasone (steroids). This combined regimen quickly resolved Trump’s COVID-19 infection.
Pfizer Vaccine study had incredible results-more than 90% effective
The Food and Drug Administration had set a bar of 50% efficacy for vaccine-makers who wanted to submit their COVID-19 vaccine candidates for emergency authorization. The Pfizer vaccine is two-dose vaccine spaced three weeks apart. The case split between vaccinated individuals and those who received the placebo indicates a vaccine efficacy rate above 90%, at 7 days after the second dose. This means that protection is achieved 28 days after the initiation of the vaccination. It’s worth considering licensed vaccines that people regularly receive to get a sense of how good these results are. On the low end, influenza vaccines are 40-60% effective at best, because the influenza virus keeps evolving into new forms year after year. By contrast, two doses of the measles vaccine are 97% effective.
Is the Pfizer vaccine safe?
No serious safety concerns have been observed in the enrolled 43,538 participants, Safety and additional efficacy data continue to be collected after the vaccine is on the market. Participants in the trial will also be monitored for two years.
Who will get the new vaccine first?
Pfizer promises to have 30 million to 40 million doses of the vaccine before the end of the year, enough for 15 million to 20 million people to get an initial shot and a booster three weeks later.
Groups that are at higher risk for infection, or are more vulnerable to the virus, are likely to get priority. That could include health care workers and public safety workers, as well as older adults who have preexisting risk factors like immune disorders, obesity, or diabetes.
When will the general public be able to get it?
Pfizer has said that it will likely apply for emergency authorization in the third week of November 2020 and say they could ramp up to 1.3 billion doses a year. However, getting the vaccine from the factory to people’s arms could pose some major challenges. The Pfizer vaccine is based on mRNA (messenger RNA), which falls apart unless it’s kept in a deep freeze. As a result, the vaccine will have to be chilled to minus 80 degrees Celsius (minus 112 degrees Fahrenheit) until it’s ready to be injected. Pfizer is designing boxes that will keep the vaccines cold as they’re being transported.
Will it work on older people?
The new results also don’t tell us whether older people will get strong protection from the vaccine. Pfizer and BioNTech’s clinical trial includes people over age 65, so it will eventually provide this crucial information. Early clinical studies have suggested that older people produce a weaker immune response to coronavirus vaccines.
What about children?
It is unknown whether children will get protection from the Pfizer vaccine. The trial run by Pfizer and BioNTech initially was open to people 18 or older. New trials testing children and adolescents are being launched.
Other Vaccine Products in Development
- Moderna Messenger RNA (mRNA) vaccine candidate is similar to Pfizer’s that produces viral proteins in the body to develop immunity. They will apply for an emergency use authorization by the end of 2020.
- AstraZeneca A newspaper in Brazil reported on Oct. 21 that a volunteer in the trial there died of Covid-19. While AstraZeneca would not comment on the case, the trial was not paused, which led outside experts to conclude that the volunteer must have received a placebo. On Oct. 23, the F.D.A. authorized the restart of the trial. AstraZeneca said in expects results from their trial by the end of December 2020.
- Johnson and Johnson Unlike other vaccines in Phase 3 trials, theirs only requires one dose instead of two. On Oct. 12, Johnson & Johnson put its trial on pause to investigate an adverse reaction in a volunteer. The trial resumed eleven days later. Despite the delay, the company expects to get results by the end of 2020.
These are just a few of the 52 vaccines that are actively in clinical trials on humans right now.
What does this all mean?
With all these positive developments, control of the COVID-19 pandemic by the Spring of 2021 is realistic. Mask use will not immediately stop after the vaccine comes out. Mask use will be required until we have built up at least 70% herd immunity either through natural infection or vaccine-induced. I estimate that in Champaign County the natural infection protection rate is around 25% right now.
I also believe that the COVID-19 vaccine will be a yearly vaccine, like influenza. The reason why the vaccine works so much better than influenza is the new messenger mRNA platform technology (which required the -80 degrees F storage). In 2022, I believe there will be combined influenza/COVID vaccine products using the mRNA platform.
-David J. Fletcher, MD