News that a SARS-CoV-2 vaccine developed by Pfizer is 90-percent effective represents "light at the end of the tunnel," according to two doctors involved in vaccine trials at Rochester Regional Health. But there are many difficulties ahead before this or any other vaccine can be widely distributed they cautioned.
Participating in a virtual press conference this morning with reporters from throughout the region were Dr. Ed Walsh and Dr. Ann Falsey. Walsh is the leader of the study at RGH and head of Infectious Diseases at RRH and Falsey is an infectious disease specialist at RRH and URMC codirector of Vaccines Trial Unit.
UMMC in Batavia is part of the RRH network of hospitals and care providers.
Pfizer announced early-stage trial results this morning. The company has not been part of the Warp Speed initiative by the Federal government to develop and distribute a vaccine for COVID-19, nor has it received government grants for the development of a vaccine, according to a spokesperson for Pfizer.
"We need to be cautious but I think it's actually a reason for optimism that the vaccines will work," Dr. Falsey said. "And I guess what I would say to the public is, you know, maybe this is the light at the end of the tunnel, and it's even more reason to wear your masks and do social distancing because I worry that fatigue sets in -- pandemic fatigue. 'It's hopeless. We're never going to get out of this.' And people develop a sort of fatalistic attitude. But I think vaccines are on the horizon. It's going to take a little while yet. But I think this is very encouraging news. I was very happy to hear it."
A story by the medical news website Stat News suggests the early results provided by Pfizer are robust, but also notes there has been no peer-review and Pfizer hasn't released a paper, known as a pre-print, with more scientific analysis.
There is a lot we don't know about the vaccine, Walsh and Falsey acknowledged, including how long it will confer immunity to the disease since today's news is based on only two months of data.
Pfizer's trial is based study of people who received the vaccine in which 94 people contracted the disease. Pfizer did not reveal how many of those 94 people received the vaccine or a placebo (neither the participants nor the doctors administering it would have any way of knowing which injection they received in a double-blind study).
"The expectation (of the public) should be that this is an interim report, and I think we all saw this on the news as well,the current guideline for safety analysis requires a longer period of time following the receipt of the second dose of the vaccine in order to feel comfortable with safety," Walsh said. "This is just two months of safety data, which is a good thing, but a final report, obviously, and assessment will be made both on safety and efficacy as they go along."
So far, only minor side effects, such as aches and a fever, have been reported from the vaccine.
Typically it takes 12 to 18 months to bring a vaccine to market but given the high fatality rate of COVID-19 and the ability of SARS-CoV-2 to spread rapidly in some circumstances, along with the dire economic consequences of the pandemic, scientists and government officials are moving quickly to find an effective and safe vaccine.
Walsh suggested that by the time the vaccine is ready for distribution -- if it ever is -- and at the earliest date distribution might start, meaning perhaps January, we will have greater confidence in its safety, especially balanced against the risk of the novel coronavirus.
"You're really weighing a risk-benefit issue," Walsh said. "We're looking at a pandemic that is potentially going to result in, if left unchecked, hundreds of thousands of more deaths in the U.S. and certainly millions worldwide. And so you try to make your best judgment as to what kind of side effects might you be missing in an early decision to deploy a vaccine. If it's been four months or five months, that's an encompassing period of time when you're generally going to see almost all of the side effects that might come from a vaccine and this type or of any type."
We're now in a period of increasing infection rates, hospitalizations, and deaths but the Pfizer results seem to have come from a period when there was a low prevalence of the disease and it's still possible SARS-CoV-2 doesn't spread as easily in warmer weather. Asked if that might skew the results of Pfizer's study Walsh said he hadn't yet thought of that question and would need some time to think about it.
If the vaccine is approved for the wider public, distribution will be a challenge.
The Pfizer vaccine must be administered in two doses three weeks apart.
It also must be stored at -112 Fahrenheit. That makes production distribution a challenge, but it also means that the vaccine can only be stored and administered from locations that a freezer capable of maintaining such a frigid temperature. That means neither your local doctor nor the pharmacy is going to be able to provide the vaccine.
A spokeswoman for RRH said it's way too early to know if UMMC is a potential distribution location. If it isn't, people in Genesee County seeking the vaccine will likely need to visit a hospital in Rochester or Buffalo.
It will take time to ramp up production of the vaccine -- though Pfizer has reportedly already started production -- and distribution will take time, so the people eligible to receive the vaccine will be prioritized in tiers with front-line healthcare workers at the front of the line followed by elderly, vulnerable people.
There's no guarantee the Pfizer vaccine will make the grade in its next phase trials but there are at least 11 other promising vaccines in development. Walsh said that's a good thing whether Pfizers proves ultimately effective or not because if there are more successful vaccines that will help supply and distribution.
The 90-percent efficacy rate for the Pfizer vaccine, if it holds up, is exceptional, Walsh said. Not all vaccines are as effective. He noted the measle vaccine is the most effective viral vaccine with an effective rate of 96 percent.
While there is much to learn yet about SARS-Cov-2 and how to vaccinate against it, both Walsh and Falsey struck upbeat notes about vaccines in general and the ability to find a vaccine to fight COVID-19.
The history of vaccines has been generally, and not universally but generally, extraordinarily successful," Walsh said. "The benefit of the vaccines that have been released over the years, over the many, many years of vaccines and going back to the 1950s, is the benefit has far outweighed any risks. I think there is that history to rely on though it is no guarantee, of course. But I think this is important, too, to recognize it and education will be important (to acceptance of the vaccine)."
Falsey added, "A lot of the vaccine hesitancy in recent years has been because vaccines have been so successful that they have nearly eradicated the terrible diseases. And so people don't understand the true impact of some of these infections and they start fixating on potential threats from a vaccine. I think with this pandemic, we can look around and see friends and family members who have been devastated.
"And so everything is risk-benefit. In addition to educating people about misinformation and the true side effects of vaccines, we can also ask them to think about risk-benefit ratios and that with 100,000 cases a day and a thousand deaths each day in the U.S., there's a significant risk to not getting vaccinated. So choosing to not accept the vaccine or not do anything is a decision, and that also carries significant risk."
