This week we saw the approval in public of Pfizer’s brand-new mRNA SARS-Cov2 vaccine under the FDA’s EUA (emergency use authorization) authority. Prior to the pandemic to see approval of something like a drug or vaccine in which all documents and transcripts are available publicly was almost unheard of.
Normally, the approval of a vaccine (or drug, device, or biologic) takes many years and for a vaccine follows a closely-scripted process culminating in something called a BLA (biologics license application). However, under the current emergency what was submitted to the FDA was the EUA application (the BLA will happen later). The document makes fascinating reading. Although in my own little world I see these kinds of documents from time to time in projects that I work on with clients, typically these documents are assessed in secret. The hearings were also streamed live on December 10th, and transcripts of both part 1 and part 2 were made available by CSPAN. If you’ve never been to any FDA public hearing it’s worth spending some time listening to see how it’s done. And for those people who’ve been drinking far too much from the vaccine conspiracy wells, have some courage to listen to what was said. This is discussion of data from the source not from someone who has an axe to grind or knows nothing about vaccine 101 development. Then when you’ve spent all day listening, make your own judgment.
The vaccine study (essentially the results of the phase 3 trial) were also published by the New England Journal of Medicine on December 10th.
Who’s Eligible for the Vaccine?
Adults are generally eligible for the vaccines but there were a long list of exclusion conditions (see trial protocol, sections 5.2 and 5.3). There were several categories that were vigorously discussed as inclusions or exclusions. The first was teenagers aged 16 to 18 years. The vote was 17 to 4 in favor with one abstention. This was interesting because out of the 18,556 people that received two doses of the vaccine across 6 countries (the trial is still ongoing), only 138 people were between the ages of 16 and 18. Importantly, in this group, no one who had the vaccine got infected during the trial, and only one teenager who got the placebo became infected. While this data tells us very little, the arguments focused on the role of these teens in society, the transmission characteristics of the virus in this group, and their potential for being hospitalized after infection. Had I been allowed to vote I would have said yes. Why? I think the vaccine presents minimal risks to this age group compared to the benefits—I don’t think a 16-year-old is fundamentally different to an 18-year-old in terms of immunology. That said, I doubt that any planned trial involving children and teens would give us meaningful data before mid-summer by which time the pandemic should be winding down in this country.
The second group were pregnant women or those breastfeeding, who were excluded from the trial. Data from the DART (developmental and reproductive toxicity) studies, which are conducted in animals to assess a vaccine’s possible effects on a fetus, won’t be available until the end of the year. This kind of data is helpful but doesn’t replace clinical data. Remarkably, the FDA has left open the possibility that pregnant and breastfeeding women may opt for immunization against the coronavirus. This is a bold decision, but I fully support it because women get to make the decision with appropriate information (yea!). To be sure there, we don’t know if there are zero risks, but based on what we do know, those risks are likely to be very minimal.
The last group concerns those who are immunocompromised, who were generally excluded from the phase 3 trial. The FDA has not specifically recommended that such people should not receive the vaccine but I think for such persons there needs to be an intensive discussion between the individual and a knowledgeable physician before vaccination takes place. In particular, I am most concerned about the large number of people who have no or poor access to healthcare and who do not have a PCP. I would not want those people getting jabs at some pharmacy without serious prior consultation.
Individuals with a significant history of allergic reaction should not get the shots. In the UK, following two incidents of allergic reactions, the government there has advised such people not to get the vaccine. This is actually pretty standard guidance for most vaccines.
Finally, the authors of the phase 3 trial indicate that safety and immune response data from the trial after immunization of adolescents 12 to 15 years of age will be reported subsequently, and additional studies are planned to evaluate BNT162b2 in pregnant women, children younger than 12 years, and those in special risk groups, such as immunocompromised persons.
Questions and Answers on COVID-19 Vaccines
What kinds of side effects can I expect?
Most participants from the Pfizer phase 3 trial who got the vaccine had some local event, primarily pain at the injection site, with a 1-7% having redness or swelling (see Figure 2 of the paper if you want to look in detail). In more than two thirds of instances those issues were classified as “mild.” Fatigue, chills, headache, and muscle pain in a third to half the subjects that got the vaccine. Most reactions were mild or moderate, meaning that the event did not interfere with activity or did interfere with activity but did not prevent daily activity.
Only 21 participants had life-threatening adverse events in the trial (0.1%) and of those only 4 were found related to the vaccine. “Relatedness” in relation to adverse events incurred during a very large clinical trial is an important concept to understand because anti-vaxxers frequently misunderstand or deliberately distort such information. I spend significant time analyzing such events and what you are looking for is the ratio of such events in the trial in comparison to a very large population. For example, if they are the same, regardless of whether someone got Guillain-Barre syndrome, a heart attack, or just dropped dead, these are of no consequence, because this is what happens in real life. What you are looking for is events related in some way to the vaccine.
The bottom line is that most people will have some discomfort and for a few percent you may be in bed for a day. If that puts you off, think of the alternative of what might happen if you don’t get the vaccine, get infected, and end up in hospital. Focus on the benefits of not contracting the virus.
Should I get the second shot?
Generally, yes. For the Pfizer vaccine efficacy is only 52% after the first dose, rising to 95% after the second dose. The only valid reason not to get the second dose in my opinion is because you had a severe reaction to the first dose, and that’s something you should discuss with your vaccine provider.
Do I have to pay for the vaccine?
No, it is free.
When can I get the vaccine?
Vaccines will generally be prioritized first for healthcare workers, the elderly, and those at highest risk of having severe forms of the infection if infected. States decide on exact priority according to their resources, so look for information from your state’s health department. It is likely by late spring that enough vaccine will be available for the people who want it.
Where can I get the vaccine?
mRNA-based vaccines, like Pfizer’s, require cold storage distribution chains, so there are some distribution issues to be sorted out. That said, while you will likely be able to get the shots from your healthcare system, many Americans will also be able to get them from their local pharmacy, such as CVS, Costco, Walmart, Rite Aid, Publix, Walgreens and Kroger, though this may take a couple of months to get going.
Do I have to get the vaccine?
No, it is voluntary at present. Any mandate is not likely anytime soon according to USA Today, and likely not to come from the federal government. Instead, employers and states may condition return or access to workplaces, schools and colleges upon getting the vaccine and mandate it once the FDA issues full approval, potentially months later.
I’ve had the coronavirus; should I still get the vaccine?
That’s a good question. My questions to you would be on how sure you are that you had an infection and how serious the infection was. Most SARS-Cov2 tests are fairly reliable but not 100%, so even though you might have had a positive test, it might be wrong. If you had moderate or severe symptoms and had a positive test, that’s a fairly good indication you had the virus and don’t need to be vaccinated. If you were asymptomatic you might have not generated enough of an immune response to guarantee you can’t be infected again.
I’ve been vaccinated; can I get infected again?
Yes, but it’s unlikely. In the case of Pfizer’s vaccine, you have about a 5% chance you could get re-infected. So, you still need to practice social distancing and wear a mask in indoor places or high human traffic areas. (Sorry!)
How long will my immunity to the coronavirus last if I get vaccinated?
At least 6 months, and probably 1-2 years, which should be long enough to get this pandemic totally under control.
If I get the vaccine, will I be “chipped?”
No. If you’re concerned about this, you’ve been hanging around conspiracy theorists for too long. Most likely you will get a paper vaccination certificate. There’s been some active discussion about some digital record but we’ve pretty much missed the boat on this one.
I’m a woman of childbearing potential; if I get the vaccine, will I become sterile?
No. This has been thoroughly debunked.
Does vaccination mean that my DNA will be altered?
Absolutely not! In the case of mRNA-based vaccines the mRNA gets into the cell’s cytosol but cannot enter the nucleus, which is where in each cell of your body your DNA resides. In the case of antigen-based vaccines there’s no genetic material involved!