The First Two Covid Vaccines Are Very Effective — But Are They Safe? Definitely Yes

Pfizer BioNTech Vaccine Efficacy vs Placebo, FDA Presentation

The light at the end of the tunnel is certainly shining brighter. The Food and Drug Administration (FDA) has granted emergency use authorization for the Pfizer-BioNTech coronavirus vaccine and the very similar-based technology Moderna vaccine. Both have demonstrated excellent efficacy — 95% and 94% protection. But and it is a major but, there is a lot of concern nationwide and internationally about vaccine safety.

My message today is that the FDA’s emergency use authorization is an assurance of safety but it is important to note that safe does not mean there are no side effects. More on side effects later.

About 170 vaccine candidates are being studied. Of those 42 are in clinical trials and, of those, 10 have reached phase III. Phase III refers to the large 30,000–40,000 plus volunteer person studies with half getting a placebo and half getting the vaccine. And finally, two of those ten have now gotten far enough along to receive emergency use authorization.

Both of these vaccines have been proven to be extremely effective and of those few individuals who did get an infection after vaccination, each was mild and there were no hospitalizations. The graphic tells the story of efficacy for the Pfizer vaccine; Moderna’s results were quite similar. Note how as time progresses an increased number of people on the placebo arm got symptomatic infection whereas only a very few who got the vaccine developed symptomatic infections.

Still, there are many safety concerns. We hear about it on the news regularly, often with the implication that is our divided politics that causes the concern. Perhaps, but vaccine concerns abound in many countries. Here is information from Kantar Health, part of Kantar Group, a large international market research company. They interviewed 1,000 representative people in each of seven countries in both June and November and from that comes the following.

Percent That Definitely Would Be Vaccinated, Kantar Health

When asked what percent would definitely get the vaccine, among Americans only forty-seven percent would do so in June and that was down to 30% in November. That is a strikingly low number. Although surveys by other organizations find a greater acceptance, willingness to obtain the vaccine is clearly suboptimal. In the Kantar survey, France and Singapore in November acceptance was 21% and 28% respectively; in Great Britain, it was 43%, not exactly stellar but substantially higher than the United States November 30%.

Green — Agree Vaccine Would Be Safe, Black — Disagree, Gray — Undecided

What percent of people agree that the vaccine is safe? Here again, only sixty-five percent of Americans with similar percentages for France and Singapore thought so. Germans, Britains, Australians, and Italians were between 69% and 75% believing the vaccines would be safe.

About 55% of Americans, 69% of French citizens, and 65% of Singapore residents were worried about the speed of the development of the vaccines. Only Germany was “low” at 41% concerned.

A substantial number of people in each country were more worried about the vaccine than the disease. In the United States, it was about equally divided with 36% more worried about the disease and 41% more worried about the vaccine with 23% undecided.

Very disturbingly, only about forty percent of people in the United States agreed that if public health authorities approved the vaccine then it would not be dangerous. Twenty-five percent feel the opposite and 35% are somewhere in between. The results from the other countries were either similar to the USA or showed somewhat less concern.

Trust That Government Make The Correct Decisions?

This comports with the thirty-eight percent of Americans who do not trust their government to make a correct decision about approval of the vaccine. Other than France at 48%, the other countries had a somewhat lower level of distrust, ranging from 12 to 32%. And of those who feel the government is a reliable source of advice, the percent is only fourteen for Americans, the lowest of all seven countries.

I’ve done a brief survey of friends and relatives. The findings parallel the Kantar data. For example, a woman who has worked in the health care field her entire career has substantial concerns in part because autoimmune diseases tend to run in her family, and, in the past, the autoimmune disease Guillain-Barre occurred in increased frequency with the 1976 flu vaccine. (According to the Centers for Disease Control (CDC,) Guillain-Barre occurred with a modest increase in incidence after the 1976 influenza vaccine to one in 100,000 vaccinations, usually within days to six weeks. There have been perhaps 1–2 cases per million vaccinations in other years.)

She still is concerned about the volunteer in the Oxford -Astra Zeneca trial that developed transverse myelitis, another autoimmune disease, despite the reviewers believing it was not vaccine-related. She has a co-worker who is afraid of the virus but says that she is equally as afraid of the vaccine; apparently, a not uncommon concern as the Kantar data indicated.

According to my college freshman grandson, on the social media sites that he uses, conspiracy theories are abounding. Some of these say that the deaths attributed to COVID are actually due to other causes or that physicians report Covid deaths because they can get a larger payment from insurers for treating coronavirus infections.

Others say that the vaccine is all a government conspiracy to implant chips so that “they can track what we do.” In his former high school, he is aware of many anti-vaccine proponents; they are “vocal and feed on other people’s concerns.”

Although almost all I have spoken to in the retirement community where I live are actually looking forward to being vaccinated. One told a friend, clearly not understanding how the mRNA vaccines work, “I don’t want them to mess with my DNA.”

With this background, let’s review some of the facts about the FDA process. The usual process is that a drug company decides to pursue a new vaccine and after months or more likely years of effort puts together their data from their preclinical or laboratory studies. They bring this to the FDA for review and request the authorization to begin a Phase I human volunteer study.

The FDA has multiple other things ongoing and so that company’s request has to, in effect, get in line so the pharmaceutical company puts its vaccine work on hold. In due time the FDA reviews the information, often goes back with some questions which in turn the company has to respond to, and at some point, the FDA does or does not approve the institution of the Phase I study.

Recall that Phase I is a limited number of individuals and is done in the case of a vaccine to look for short term safety issues but also to see if the vaccine produces a meaningful antibody response, the latter being the best current marker that the vaccine might protect people from the infectious agent. When the Phase I study is completed, the company goes back to the FDA with their data. It gets in line again.

The FDA then reviews it and, if they have questions for the company, there is a back and forth. At some point, if the data is deemed adequate, the pharmaceutical company is allowed to start the Phase II study which is essentially a larger number, perhaps a few hundred, of individuals to look both for safety and antibody response.

Again, the back-and-forth process and if all goes well the FDA approves starting a Phase III study. This is the study that enlists some 30,000–40,000 plus volunteers, half being randomized to placebo and half being randomized to receive the new vaccine. At the end of the study, the company then puts the data together and submits it to the FDA for review.

There is often back and forth for questions and sometimes requests for additional information. Then, if all goes well and the FDA thinks that this is an approvable vaccine, they call together an external expert review group. If the expert group deems the data compelling, they will vote and the FDA takes the vote under consideration.

Although it does not have to follow the advisory committee’s advice, it usually does so. The FDA then issues an authorization for the vaccine or in the case of a pandemic as with Covid-19, they issue an emergency use authorization. In normal circumstances, this whole process takes four or more years from concept to approval.

With Operation Warp Speed the process is essentially the same regarding all of the steps that have to be done but they have made an enormous effort between both the pharmaceutical companies and the FDA to shorten what we might call the “downtime.” They began last spring to agree on common protocols for all the drug companies to follow once Phase I and II were given the go-ahead.

The FDA reviews data on an ongoing basis rather than waiting for all the data to come in at one time. The FDA has set other work aside in the vaccine group so that that full attention could be given to the COVID vaccine work. This means they give immediate attention as the information comes in, with data review, with impressions back in real-time to the pharmaceutical company, often the same day as they receive the information and with the anticipation that the drug company will be responding in return.

The leader of the vaccine group, Dr. Peter Marks, has been with the FDA since 2012, coming from a career in patient care and research at Harvard and Yale plus experience in the public health field. He fully understands the necessity of assuring Americans that any vaccine given emergency use authorization is both safe and effective.

So, what is required by the FDA to satisfy the emergency use authorization? First of course is proof of efficacy. As you know, both the Pfizer and the Moderna vaccines have proven to be more about 95% percent effective. And the FDA has insisted on two months of follow-up of all the volunteers for safety monitoring purposes. Why two months? Because the FDA has found over the years that if there are safety problems with any vaccine candidate, these almost always arise in the first two months after vaccination.

The process then moves on to the outside advisory group which in this case was scheduled long in advance so it could meet as soon as the FDA had finished its work. The FDA finished its Pfizer vaccine analysis on a Monday afternoon, got the information out to the advisory group and it met virtually that Thursday, December 10th. After the meeting, they voted in favor and the FDA then issued an emergency use authorization the following day. The same process was with the Moderna vaccine, exactly one week later. Recognizing the importance of transparency, in both cases, the FDA made their analysis immediately available to the public at the same time that it sent it out to the advisory committee. I should add that those 40,000 volunteers in each study are all being followed for a minimum of two years to look for any potential long-term complications.

So far there have been no safety issues. But as I mentioned earlier there can certainly be side effects. The Pfizer vaccine data as published by the FDA shows that among individuals 18–55, fever occurred in fifteen percent (placebo volunteers — <1%,) fatigue in fifty-nine percent (placebo 23%, headache in fifty-two percent (placebo 24%,) chills in thirty-five percent (placebo 4%,) muscle pain in thirty-seven percent (placebo 8%,) joint pain in twenty-two percent (placebo 5%,) and diarrhea in ten percent (placebo 8%.) In those who were 55 or older, the side effects were fewer than in the younger age group. Most of these side effects occurred in the first thirty-six hours and dissipated by the end of that time. However, it is important to note that in about five percent of people, the side effects were labeled as severe defined as limiting the individual’s daily activities. The importance of a placebo was also demonstrated as the data above make clear that side effects also occurred but at a lesser rate in the volunteers who received the placebo.

So, side effects are real. They occur and need to be understood. It is also important to point out that two people vaccinated in England developed a serious allergic reaction. Both were individuals that had a long history of such reactions and came prepared with their injectable adrenaline (EpiPen’s.) The exact cause of the allergic reaction is still under investigation but among the ingredients, possible culprits are the lipids ALC-3015, which is known to rarely cause reactions, or polyethylene glycol (PEG).

If you can accept common side effects and the uncommon but possible allergic reactions but are still concerned about safety, what can be done to overcome your concerns?

First is to understand the process that is used by the FDA; hopefully, I have given that some clarity. But from this point on there is going to be a need for a coordinated messaging process and ample transparency. The FDA has been highly transparent making the data available online for Pfizer and Moderna as presented to the Advisory Committee. It also made the committee meeting online in real-time. You might want to look at those documents (see the links above); scroll down to the sections on Side Effects and Safety. It is always better to “see for yourself” and then spend some time discussing it with your healthcare provider, although don’t be surprised if he or she has not read the original report themselves.

Since “the government” is mistrusted by many as the survey demonstrated, it will take more than government agencies or leaders urging people to get the vaccine, important as that is. There will need to be consistency in the messaging. It cannot be that some are suggesting, as has been the case of masks, to wear a mask where other leaders refuse to wear a mask.

Dr Freeman Hrabowski Volunteering In the Vaccine Trial

And there needs to be “positive norming.” This is where those who are in favor make their case in a way that is “come join me.” Here are a few examples. Dr. Freeman Hrabowski is the President of the University of Maryland Baltimore County (UMBC). An African American, he and his wife volunteered for a vaccine study. They were photographed getting their vaccines and this was made available throughout the African American community. Dr. Hrabowski was doing this in part to assure the Baltimore African American community, which has long been concerned about inappropriate research studies. Dr. Mohan Suntha, the CEO of the 14-hospital University of Maryland Medical System wrote an open letter to all staff. He did not request or require staff to be vaccinated but certainly encouraged it. Then he explained why he would be getting the vaccine when it was his turn. First, he had reviewed the FDA database and was convinced that the vaccines were both safe and effective. Second, he recognizes that as a physician and a leader he will set an example by what he does or does not do. Finally, he noted that he was the father of two young children and the son of aging parents. “Taking a vaccine that I believe is proven to be safe and effective is an easy decision, especially if it helps keep my loved ones healthy, too.” I found his message to be on target, not imploring or threatening but inspiring.

Three former presidents, Clinton, Bush, and Obama have all pledged to receive the vaccine, when it is due in their personal demographic group, publicly and on live TV. Both President-elect Biden and current vice president Pence have been photographed getting vaccinated. Vice president-elect Kamala Harris is due December 28th.

So, what should you do? Do a risk/benefit analysis for yourself. Risk — no serious side effects have been observed in the greater than 15,000 volunteers in each study who received either vaccine. Yes, there were side effects, some of them quite unpleasant. Most of them dissipated in the first thirty-six hours but not all. I have personally had some severe side effects in the past, specifically from the shingles vaccine and it was most unpleasant. But they did pass so I am well aware of how a vaccine can cause unpleasant side effects for a short period of time. The benefit of the coronavirus vaccine, of course, is protection from a deadly disease and I am of an age (79) where infection can be more severe, lead to hospitalization, and even death.

Based on my risk-benefit analysis, my plan is to get vaccinated as soon as a vaccine becomes available for my demographic group. I want to protect myself but also my family and, living in a retirement community of 2000 residents, I want to protect others. You need to make a similar risk-benefit analysis for yourself and do what then seems best for you.

Stephen C Schimpff, MD, MACP, is a quasi-retired internist, professor of medicine, former CEO of the University of Maryland Medical Center, and senior advisor to Sage Growth Partners. He is a graduate of Yale Medical School and is board-certified in internal medicine, medical oncology, and infectious disease. He has written 6 books for the general public on medicine, health, and wellness.


Make informed choices about your Health

Stephen Schimpff MD, MACP

Written by

Quasi-retired physician, academic medical center CEO, professor & researcher. Author of 6 health & wellness books.



A Medika Life Publication for the Medical Community

Stephen Schimpff MD, MACP

Written by

Quasi-retired physician, academic medical center CEO, professor & researcher. Author of 6 health & wellness books.



A Medika Life Publication for the Medical Community

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