While the Biden administration has run againstagainst COVID-19, government researchers have also been working on what form the next generation of vaccines will take.
They can be combined with the seasonal flu vaccine or could come in the form of pills or spots instead of shots. Researchers also envision vaccines that can protect against viruses in addition to SARS-CoV-2 (the virus that causes COVID-19) that can prevent future pandemics.
And they assess whether those who are fully vaccinated may need booster shots later in the year. Additional shots could be almost identical to the initial doses, given as a protection against the possibility of weakened immunity or adjusted to defend against mutant strains giving rise to concern.
The three largest vaccine manufacturers with shots approved in the US, Pfizer, Moderna and Johnson & Johnson, are planning – or are already trying – an extra shot. The booster shots are expected to be very similar to the current vaccines, but may come in a smaller dose.
“With a lot of vaccines, we understand that at some point we have to boost, whether it’s 9 months, 12 months. And we’re preparing for that,” says Dr. David Kessler, chief science officer for the administration’s COVID-19 response, told lawmakers.
Boosters can also be mixed with the annual seasonal flu shot. Moderna said it plans early trials with this kind of combined shot this year. Other combinations of vaccines are already often used to immunize younger children against several diseases during a single doctor’s visit.
However, administration officials say no decision has yet been made on how booster shots would be used – or whether it would even be necessary.
What about varieties?
While booster shots renew the body’s immunity to the virus by mimicking parts of the original strain first identified in China, vaccine manufacturers are also trying to adjust their doses to address newer variants of SARS-CoV-2, some of which spread faster and can cause more serious illness.
This is not unusual; seasonal flu vaccines are changed regularly to address mutations seen in the virus around the world.
Dr. John Mascola, head of the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases, says understanding the mutations of SARS-CoV-2 is “a major focus” for federal researchers.
The NIH has set aside funding and researchers from across its campus to answer key questions about variations in the virus. Some researchers are focused on testing the effect of mutations on vaccine efficacy. Others are working to better understand and map its “epitopes,” spots where antibodies can target SARS-CoV-2’s signature girl protein.
“It’s a kind of basic scientific knowledge that can control antibody therapies in the long run, but also control vaccine design. Basically, I say, ‘Can I understand how the virus is going to escape, and can I explain it,'” Mascola explained.
Moderna and Pfizer are both pursuing possible versions of their doses adjusted to the B.1.351 variant, first seen in South Africa, although research so far suggests that their current vaccines may remain most effective against the mutant. The AstraZeneca-Oxford vaccine, which is not approved for use in the United States, has been shown toagainst the South African variant.
“The reason they choose that strain is that it’s one of those we know of now, with the variants of concern that are out there, it’s the most antigenically different,” Mascola said.
Mascola also raised the possibility that the development of a booster with the South African variant could provide more protection.
“For example, if we boost with the B.1.351 strain and we see that the serum antibodies are broader, they neutralize not only the original strain but also B.1.351 and other variants, then that may be a preferred approach,” Mascola added. .
Skip the needle
Significant efforts are also underway to come up with vaccines that do not rely on needles and syringes to be administered, after record demand strained the complex global supply chain in the midst of the pandemic. Some projects could make it easier to store and transport the vaccine without the expensive freezers and dry ice currently required for the Moderna and Pfizer vaccines.
For example, future doses may be inhaled through the nose instead of being shot into the arms. The NIH recently announced promising results from a single-dose intranasal vaccine tested on monkeys similar to AstraZenecas.
The Biomedical Advanced Research and Development Authority (BARDA) also last year announced millions of dollars in contracts to develop a handful of other alternatives provided by portable stains or pills, using the agency’s experts to shepherd developers through early trials and regulatory approvals.
Vaxess Technologies claims that its self-applied patch is shelf-stable and painless and delivers its vaccine through microscopic “protrusions” that dissolve in the skin.
“We are working with companies on the various technologies to potentially collaborate with the six vaccine candidates currently being supported by the U.S. government,” said BARDA Director Gary Disbrow.
BARDA hopes that companies can show in smaller trials that they trigger the same kind of immune response as the currently approved vaccine doses, which can speed up their availability to the public.
“The technologies have been shown for other viral pathogens, but we are trying to support them for the clinical trials. And again, the timing really depends on whether we can identify these correlates for protection,” Disbrow added.
A “pan-coronavirus” vaccine
Researchers at the Walter Reed Army Institute of Research recently announced early trials with a vaccine that relies on a “spike ferritin nanoparticle” that has shown some promising results against variants of SARS-CoV-2 as well as the previously related virus known as SARS- CoV-1.
“Over the last four years, we’ve been working to try to move away from a virus, a vaccine. And try to really have vaccines for the future,” said M. Gordon Joyce, a senior researcher at WRAIR’s new Department of Infectious Diseases. .
Unlike the other currently approved vaccines, WRAIR’s experimental doses are designed to deliver engineered triplets of the spike proteins they hope will train immune systems to produce a greater amount and diversity of antibodies. Like other classic “protein vaccines”, developers say these doses can prove to be more robust than vaccines that require carefully controlled climates to stay stable.
The researchers say they are in talks with commercial partners for possible next steps to their shot. The current batch of doses being tested could be developed into a “variant-proof” vaccine, booster shot or serve as a “principle-proof” for future vaccines targeting broader groups of coronaviruses.
“We did not think we would already be here with a pan-SARS-like virus vaccine, but it looks like we might be there,” said Kayvon Modjarrad, director of WRAIR’s new Infectious Diseases Department.