US Army’s coronavirus 'super vaccine': What we know, and don’t know
Study shows 'broader protection' from spike ferritin nanoparticle
Highlights
- Results of pre-clinical trials show "promise".
- The vaccine formulation known as SpFN has shown to elicit a potent immune response.
- It also being touted to provide broad protection against SARS-CoV-2 variants of concern as well as other coronaviruses.
A NEW "super vaccine" against SARS-COV-2 being developed by US Army researchers could tackle the virus that causes COVID-19 in all its mutations. It is touted to work against Omicron, Delta and all the previous variants, and even SARS-CoV-1, first detected in 2003.
Known as the Spike Ferritin Nanoparticle (SpFN) COVID-19 vaccine, its creators from the US military lab say the shot generates strong binding antibody responses against the receptor-binding domain and spike proteins of all variants of concern.
What we know so far:
Why is it being called a “super vaccine”?
It’s a term used by the Western media to describe the SARS-CoV-2 vaccine that presents eight “prefusion-stabilised spike glycoprotein trimers” in an ordered array on a spike ferritin nanoparticle (SfNP).
The vaccine is being developed by researchers at the Walter Reed Army Institute of Research (WRAIR) in Silver Spring, Maryland. It has demonstrated "potent neutralising antibody responses" against coronaviruses, the initial published study shows.
It creators said the data support further development of the vaccine as one that may be broadly applicable to "multiple sarbecovirus lineages" — highly-potent and broadly-neutralising antibody responses against major SARS-CoV-2 variants of concern, including the earlier SARS-CoV-1 virus first identified in February 2003, during an outbreak that emerged in China.
Lab data were published in the journal Nature (NPJ Vaccines) on October 28, 2021. The team led by Kathryn McGuckin Wuertz of the US Military HIV Research Program, Center for Infectious Diseases Research, Walter Reed Army Institute of Research in Maryland, said their shot is "adjuvanted" (enhanced) with what they call as the "Army Liposomal Formulation" QS21 (SpFN-ALFQ).
SpFN forms part of a forward-thinking "pan-SARS" strategy by the US military that aims to address the current pandemic and acts as a first line of defense against variants of concern and similar viruses that could emerge in the future.
This vaccine stands out in the COVID-19 vaccine landscape. The repetitive and ordered display of the coronavirus spike protein on a multi-faced nanoparticle may stimulate immunity in such a way as to translate into significantly broader protection.
What vaccine platform it based on?
Scientists in WRAIR's Emerging Infectious Diseases Branch (EIDB) developed the SpFN nanoparticle vaccine.
Dr. Kayvon Modjarrad, director of the Emerging Infectious Diseases Branch at WRAIR, co-inventor of the vaccine and the Army lead for SpFN told US media: “The accelerating emergence of human coronaviruses throughout the past two decades and the rise of SARS-CoV-2 variants — including most recently Omicron — underscore the continued need for next-generation preemptive vaccines that confer broad protection against coronavirus diseases.”
The US Army’s strategy is to develop a “pan-coronavirus” vaccine technology that could potentially offer safe, effective and durable protection against multiple coronavirus strains and species, Modjarrad explained.
How effective is it?
Results of “pre-clinical” trials show promise. Trial results published recently in Science Translational Medicine indicate that the SpFN vaccine protects "non-human primates” from disease caused by the original strain of SARS-CoV-2.
More importantly, it also induces highly-potent and broadly-neutralising antibody responses against major SARS-CoV-2 variants of concern — as well as the earlier SARS-CoV-1 virus that emerged in 2002.
Is there another COVID vaccine being developed by the US military?
Yes. WRAIR developed a secondary candidate vaccine, a SARS-CoV-2 Spike Receptor-Binding Domain Ferritin Nanoparticle (RFN) vaccine.
Unlike the SpFN candidate vaccine, the RFN shot targets a smaller part of the coronavirus Spike protein.
Results from a study, published recently in the journal Proceedings of the National Academy of Sciences (PNAS), show that this vaccine potentially offers similar protection against an array of SARS-CoV-2 variants, as well as SARS-CoV-1.
What are the advantages of such vaccines?
”The RFN vaccine candidate is more compact and has some natural advantages as we try to increase the immune response against multiple coronaviruses using a single vaccine platform, so it is still under consideration as part of our pan-coronavirus vaccine development pipeline," said Dr. Gordon Joyce, WRAIR structural biologist and vaccine co-inventor.
"The threat from COVID-19 continues as it evolves, and eventually there will be other emerging disease threats," said Dr. Nelson Michael, director of the Center for Infectious Diseases Research at WRAIR. "Our investment in developing a next generation vaccine is an important step towards getting ahead of COVID-19 and future disease threats."
What’s the timeline of this “super vaccine” development? Who will produce it?
SpFN entered Phase 1 human trials in April 2021. Early analyses — expected to conclude soon — will provide insights into whether SpFN's potency and breadth, as demonstrated in preclinical trials, will carry over into humans.
Mass production will only be done following completion of extenstive Phase 3 trials on humans showing it is both safe and effective. It will then have to go through approval process by the US drug regulators (FDA). At this point, is unclear what entity will be tasked to mass produce it, after passing regulatory hurdles.
What is the benefit from the SpFN jab?
The SpFN-ALFQ vaccine candidate is now currently under assessment in a clinical (human) Phase 1 clinical trial (ClinicalTrials.gov Identifier: NCT04784767). Clinical trial data will allow researchers to compare SpFN's immune profile to that of other COVID-19 vaccines already authorized for emergency use.
"This vaccine stands out in the COVID-19 vaccine landscape," Modjarrad said. "The repetitive and ordered display of the coronavirus spike protein on a multi-faced nanoparticle may stimulate immunity in such a way as to translate into significantly broader protection."
What do other experts say about the new candidate vaccines?
If the shot does work as expected, it could “quite possibly" mean bringing us a step closer to the end of the coronavirus pandemic, said Dr Simon Clarke, associate professor of microbiology at University of Reading, who was not part of the study.
“It could mean you could vaccinate against multiple variants in one go. You could probably do that anyway if you mix together, say, different mRNA vaccines. You would probably get some protection. It’s just another way of delivering protection, or hopefully, immunity to several different types or variants at the same time,” Dr Clarke told TRT World in an interview.
“That does not mean, of course, that the immunity you get through those viruses won’t wane over several months, like we see with the current situation,” Dr. Clarke said.