A Blog by Jonathan Low

 

Jan 30, 2021

Why New Covid Vaccines Complicate Public Inoculation

As more vaccines become available and the public is made aware of their differences, there are concerns that some will demand a certain vaccine. The problem is that, for the time being, there is simply not enough of any vaccine to warrant choice so people are being urged to take whichever vaccine is available to them in order to stop the spread, which is also encouraging ever more new variants. 

Eventually, it may be possible to assign vaccines on the basis of a subject's age, gender and health issues. But eventually is not now, nor is it the immediate future. JL

Andrew Joseph and Olivia Goldhill report in Stat:

All vaccines are not equal, and increasingly, health authorities and providers will be dealing with shots with varying attributes: different storage requirements, efficacy, dosing regimens, and manufacturing platforms. That, plus the possibility of a pickier public who may want a certain shot over another, could complicate an already-messy rollout. As more vaccines get authorized, health officials could recommend that certain people, based on age or other risk factors for more severe Covid-19, are prioritized for certain shots.

It’s always good for consumers to have options, right? And indeed, the United States should soon have three Covid-19 vaccines being injected into people’s arms, with more potentially on the way in the coming months, accelerating the race to vaccinate hundreds of millions of people as quickly as possible.

But all vaccines are not equal, and increasingly, health authorities and providers will be dealing with shots with varying attributes: different storage requirements, efficacy, dosing regimens, and manufacturing platforms. That, plus the possibility of a pickier public who may want a certain shot over another, could complicate an already-messy rollout. But the different features also open the door to greater access beyond just more supply — a more convenient one-shot vaccine will likely soon be available.

The main point, experts stress, is how remarkable it is the U.S. has multiple Covid-19 vaccines just a year into the pandemic. All the immunizations that regulators authorize will have been shown to be safe and effective, so you should get whichever one you have the opportunity to get, they say.

“In the event that you have the choice to get vaccinated, I’d encourage you to take the vaccine that you’re given,” John Brooks, the chief medical officer of the Centers for Disease Control and Prevention’s Covid-19 response, said at a briefing Friday.

Johnson & Johnson, which on Friday reported its vaccine was 66% effective in preventing moderate to severe disease and 85% effective in preventing severe Covid-19 in clinical trials, plans to file for emergency use authorization with the Food and Drug Administration in early February. Presuming regulators move quickly, health authorities will have the advantage of a third shot to distribute with millions more in supply.


Unlike the two-dose mRNA vaccines already authorized from Moderna and Pfizer-BioNTech, the J&J vaccine requires only one dose. It is also cheap, and can be kept in normal refrigerators, making it easier to store and transport than the mRNA vaccines, which have to be kept at subzero temperatures, sometimes in special freezers that smaller clinics might not have.

“That’s going to be huge for rural populations,” Alan Morgan, the CEO of the National Rural Health Association, said about J&J’s shot.

Similarly, it could now be easier for vaccine campaigns to go out into communities instead of requiring people to come to hospitals to get vaccinated, which could reach people who don’t have access to health care or who are mistrustful of health institutions but may listen to community leaders. Polling data, for example, have shown that people of color, who have faced historic and ongoing mistreatment by medical providers, are less likely to get Covid-19 vaccines as quickly as other people. Plus, early vaccine distribution data show disproportionately low numbers of Black and Latino adults have received shots.

“It’s easier to bring the vaccine to hard-to-reach areas,” Mitchel Rothholz, chief of staff of the American Pharmacists Association, said about J&J’s vaccine.

Some people, however, may want to pick their vaccine as if it were a piece of produce they could squeeze to find the choicest option. Clinical trial results or reports about side effects could steer what people want.

It’s difficult to compare clinical trials of different products against each other. The pandemic has also changed: J&J’s trial occurred as at least one variant that appears to have some impact on vaccine efficacy was circulating, while the Moderna and Pfizer-BioNTech trials were completed before variants of concern started transmitting widely. Without clinical data to evaluate each vaccine against the newer strains, it’s difficult to determine if the existing Covid-19 vaccines could be less effective against variants of the virus.

Still, some people might remember the headlines of Moderna’s and Pfizer’s product offering greater than 90% effectiveness against Covid-19 and question J&J’s announcement of 66% effectiveness.

Public health officials were quick to tout J&J’s data as a strong result, particularly given that regulators initially said a vaccine would only have to be 50% effective to be authorized. A vaccine that’s 66% effective is an incredibly powerful tool in fighting respiratory viruses, they stressed. “We would be celebrating a seasonal influenza vaccine with 60% efficacy,” Jay Butler, the deputy director for infectious diseases at the CDC, told reporters.

In the U.S. arm of the clinical trial, J&J’s vaccine was 72% effective, which, in the absence of the mRNA data, “one would have said this was an absolutely spectacular result,” Anthony Fauci, the head of the National Institute of Allergy and Infectious Diseases, said at a separate White House briefing. What’s more, the immunization was 85% effective at preventing severe disease and, in the trial, all hospitalizations and deaths occurred among people who got the placebo. None of the vaccinated people diagnosed with Covid-19 got sick enough to need hospital care.

“If it comes to getting my family members vaccinated, and all that’s available is J&J or Novavax, I’d tell them to take it,” said Robert Hancock, president of the Texas College of Emergency Physicians.

Novavax is another vaccine maker that, on Thursday reported that its vaccine was 90% effective in one trial in the United Kingdom, but 49% effective in another trial in South Africa, likely because of the B.1.351 variant circulating in that country, which appears to evade some aspects of the immune response. The company has not said when it might apply to the FDA for authorization.

The differing efficacy levels among vaccines could also complicate the logistical advantages J&J’s shot provides. If states started allocating J&J’s shot only to rural areas, “there may be concerns that that’s inequitable,” said Marcus Plescia, chief medical officer of the Association of State and Territorial Health Officials. “People in rural areas might feel like they’re getting short shrift.”

Julie Swann, the head of the department of industrial and systems engineering at North Carolina State University, who advised the CDC during the H1N1 pandemic, agreed. She said providers should start surveying their communities to see whether people have a preference for which vaccines they receive. “It would be a real mistake to distribute J&J solely based on infrastructure,” she said.

Eventually, as more vaccines get authorized, health officials could recommend that certain people, based on age or other risk factors for more severe Covid-19, are prioritized for certain shots. Perhaps the mRNA vaccines could be reserved for people who are most vulnerable to the coronavirus, suggested Swann, while the J&J vaccine could be deployed to more general populations.

For now, federal health officials haven’t issued guidelines for who should get which vaccines.

Another question looms for the vaccine drive: the variants. It appears that B.1.351 has some impact on at least some of the vaccines, though experts note that immunizations don’t work like light switches that are either on or off. Rather, people vaccinated may be less defended from getting infected against B.1.351 than other forms of the coronavirus, but the vaccines could still protect them from getting severe Covid-19.

For now, health authorities and companies say the emergence of B.1.351 and other variants serves as a signal they need to be ready to adapt vaccine designs if and when a form of the virus emerges that could significantly “escape” the immune protection conferred by vaccines. Some vaccine makers have started studying booster shots engineered specifically against B.1.351, and federal health authorities said Friday they are reviewing contingency plans to tweak the vaccines if needed.

“We will continue to see the evolution of mutants,” Fauci said. “We, as a government, the companies, all of us that are in this together will have to be nimble to be able to adjust readily to make versions of the vaccine … specifically directed towards whichever mutation is actually prevalent at any given time.”

The variants add pressure to the vaccine campaigns in other ways. B.1.351 and other variants that have been confirmed in the United States appear to be more infectious than earlier forms of the virus, which means a higher proportion of the population will need to be vaccinated to drag down the U.S. epidemic. If more people get vaccinated and cases decrease, that lowers the chance of even more nefarious variants popping up.

“The sooner we can get people immunized, the better chance we have that this will not keep happening with more and more variants emerging because there’s such a large population of viruses,” Francis Collins, the director of the National Institutes of Health, told reporters Friday.

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