Vaccine Info

SpFN COVID-19 Vaccine

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Last reviewed
May 8, 2022

SpFN COVID-19 Vaccine Description For 2022

The Spike Ferritin Nanoparticle COVID-19 vaccine (SPFN_1B-06-PL) was developed internally at the Walter Reed Army Institute of Research (WRAIR). The vaccine employs ferritin, a protein found in almost all living organisms. By attaching a specific type of spike protein to a polymerized version of ferritin, WRAIR scientists hope the resulting vaccination dose will block SARS-CoV-2 coronavirus infections that cause COVID-19.

Ferritin has a unique structure with 24 sides, all of which can attach to a different viral protein. By using ferritin in a pan-coronavirus vaccine, the nanoparticle can produce an array of varying coronavirus antigens not just from SARS-CoV-2 variants but other coronavirus species and strains.

The spike protein sequence was derived from the Wuhan-Hu-1 genome sequence (GenBank accession number: MN908947.3). The spike protein ectodomain was modified to introduce two proline residues (K986P, V987P) and remove the furin cleavage site (RRAS to GSAS). An adjuvant, Army Liposome Formulation (ALFQ) containing QS21, was mixed with the SpFN vaccine at room temperature.

Preclinical study results show that the SpFN COVID-19 vaccine elicits a potent immune response but may also provide broad protection against the SARS-CoV-2 betacoronavirus variants of concern and other coronaviruses. The ongoing phase 1 clinical study in humans is sponsored by the U.S. Army Medical Research and Development Command, with collaborators: WRAIR and Henry M. Jackson Foundation for the Advancement of Military Medicine. As of June 11, 2021, 24 individuals have participated in the trial. Volunteers must meet specific inclusion and exclusion criteria—most notably, they have never been infected with COVID-19 or received a COVID-19 vaccine.

The journal Nature published an article on Dec. 13, 2021, revealing a recent study concluded: 'that a nanoparticle vaccine, combined with a potent adjuvant that effectively engages innate immune cells, enhances SARS-CoV-2-specific durable adaptive immune T cell responses.' And the peer-reviewed journal Science published a Research Article on December 16, 2021: A SARS-CoV-2 ferritin nanoparticle vaccine elicits protective immune responses in nonhuman primates. Conclusion: 'The immune response elicited by SpFN vaccination and resulting efficacy in nonhuman primates supports the utility of SpFN as a vaccine candidate for SARS-causing beta coronaviruses.'

Walter Reed Army Institute of Research is located in Silver Springs, MD, founded in 1893 to protect against infectious disease threats. WRAIR conducts basic and applied research that promotes psychological resilience, enhances neurological functioning, and improves operational readiness among U.S. Service Members. 

SpFN COVID-19 Vaccine History

Scientists in WRAIR's Emerging Infectious Diseases Branch developed the SpFN nanoparticle vaccine, based on a ferritin platform, as part of a forward-thinking "pan-SARS" strategy. In nonhuman primates, they developed and evaluated an adjuvanted SARS-CoV-2 spike ferritin nanoparticle (SpFN) vaccine. 

Nonhuman primates received a high-dose (50 μg) SpFN vaccine, given twice 28 days apart, induced a Th1-biased CD4 T cell helper response and elicited neutralizing antibodies against SARS-CoV-2 wild-type and variants of concern, as well as against SARS-CoV-1. These potent humoral and cell-mediated immune responses translated into rapid elimination of replicating virus in the upper and lower airways and lung parenchyma of nonhuman primates following the high-dose SARS-CoV-2 respiratory challenge. 

SpFN COVID-19 Vaccine Indication

SpFN SARS-CoV-2 vaccine is indicated to prevent COVID-19 disease caused by the SARS-C0V-2 virus.

SpFN COVID-19 Vaccine Effectiveness Against Coronavirus Variants (Omicron)

On December 21, 2021, stated: "With Omicron, there's no way really to escape this virus. You're not going to be able to avoid it. So I think pretty soon either the whole world will be vaccinated or have been infected," stated Dr. Kayvon Modjarrad, director of Walter Reed's infectious diseases branch. As of May 5, 2022, the U.S. NIH OpenPortal has not ranked the SpFN vaccine candidate's therapeutic activity against SARS-CoV-2 variants.

SpFN COVID-19 Vaccine Dosage - Phase 1 Study

Phase 1 study with 29 participants is sponsored by the U.S. Army Medical Research and Development Command - First Posted: March 5, 2021 - Estimated Primary Completion Date: October 30, 2022 - Biological: 25 µg SpFN_1B-06-PL + ALFQ (QS21 Adjuvant) Drug: Sodium chloride, USP, for injection (0.9% NaCl); and Biological: 50 µg SpFN_1B-06-PL + ALFQ (QS21 Adjuvant). Last Update Posted: September 14, 2021.

SpFN COVID-19 Vaccine News For 2021 - 2022

April 21, 2022 - Newstalk radio reported Prof Luke O’Neill, a professor of biochemistry at Trinity College Dublin said .... “Amazingly, it protects against SARS – the original virus – SARS-CoV-2, Alpha, Beta, Delta, Omicron. It protected against all of those in the monkeys – now again, that’s a tremendous result."

April 19, 2022 - The journal Nature published: Pan-coronavirus vaccine pipeline takes form.

March 28, 2022 - A non-peer-reviewed study - A SARS-CoV-2 Spike Ferritin Nanoparticle Vaccine is Protective and Promotes a Strong Immunological Response in the Cynomolgus Macaque COVID-19 Model. Conclusion: Vaccination resulted in robust cell-mediated and humoral responses and significantly reduced lung lesions following SARS-CoV-2 infection. The strength of the immune response suggests that dose sparing through reduced or single dosing in primates may be possible with this vaccine. Overall, the data support further evaluation of SpFN as a SARS-CoV-2 protein-based vaccine candidate with attention to fractional dosing and schedule optimization.

January 30, 2022 - CNET published a news article written by Peter Butler: The U.S. Army's "pan-coronavirus" vaccine could protect against any COVID variant.

January 12, 2022 - CNET wrote: The Army's vaccine, SpFN, shows promise against all COVID-19 strains, including omicron, and could shield patients against any infection in the coronavirus family.

January 6, 2022 - Maryland-based CAMRIS International, LLC, an HJF Company, announced its involvement in COVID-19 vaccine research by the Walter Reed Army Institute of Research. That SpFN platform is manufactured in WRAIR's Pilot Bioproduction Facility in Silver Spring, MD, and is the only cGMP-compliant pharmaceutical manufacturing plant in the U.S. Army and the Department of Defense.

December 16, 2021 - A new research article published by SCIENCE TRANSLATIONAL MEDICINE: A SARS-CoV-2 ferritin nanoparticle vaccine elicits protective immune responses in nonhuman primates - concluded by stating, 'The immune response elicited by SpFN vaccination and resulting efficacy in nonhuman primates supports the utility of SpFN as a vaccine candidate for SARS-causing beta coronaviruses.'

December 16, 2021 - published 'Series of preclinical studies supports the Army's pan-coronavirus vaccine development strategy.'

December 13, 2021 - The journal NPJ Vaccines published a study: SARS-CoV-2 ferritin nanoparticle vaccine induces robust innate immune activity driving polyfunctional spike-specific T cell responses. 'Our study reveals that a nanoparticle vaccine, combined with a potent adjuvant that effectively engages innate immune cells, enhances SARS-CoV-2-specific durable adaptive immune T cell responses.'

August 8, 2021 - A review was published: Nanoparticles in the clinic: An update post-COVID-19 vaccines. 

September 21, 2021 - PNAS published a RESEARCH ARTICLE - Efficacy and breadth of adjuvanted SARS-CoV-2 receptor-binding domain nanoparticle vaccine in macaques. 'Our results support consideration of RFN for vaccine development against multiple concerning members of the Sarbecovirus subgenus of Betacoronaviruses.'

May 10, 2021 - A non-peer-reviewed study: SARS-CoV-2 ferritin nanoparticle vaccines elicit broad SARS coronavirus immunogenicity. 'A Spike-ferritin nanoparticle (SpFN) vaccine-elicited neutralizing titers more than 20-fold higher than convalescent donor serum, following a single immunization, while RBD-Ferritin nanoparticle (RFN) immunogens elicited similar responses after two immunizations. Passive transfer of IgG purified from SpFN- or RFN-immunized mice protected K18-hACE2 transgenic mice from a lethal SARS-CoV-2 virus challenge. Furthermore, SpFN- and RFN-immunization elicited ACE2 blocking activity and neutralizing ID50 antibody titers >2,000 against SARS-CoV-1, along with high magnitude neutralizing titers against major VoC.'

April 28, 2021 - A non-peer-reviewed study findings reveal that a nanoparticle vaccine, combined with a potent adjuvant, generates effective SARS-CoV-2 specific innate and adaptive immune T cell responses that are key components to inducing long-lived immunity.

April 7, 2021 - Scientists say that the Army-developed COVID vaccine could 'stop variants in their tracks. "We have designed and positioned this platform as the next-generation vaccine, one that paves the way for a universal vaccine to protect against not only the current virus but also counter future variants, stopping them in their tracks before they can cause another pandemic," Kayvon Modjarrad, director of Walter Reed's emerging infectious diseases branch, said in a statement. 

January 14, 2021 - The vaccine being developed by Walter Reed, SpFN, differs from other vaccines. It uses a soccer-ball-shaped protein, allowing scientists to harness the spikes of multiple coronavirus strains on 24 different faces of the protein. This unique difference may answer the coronavirus mutations that have begun to circulate.

October 16, 2020 - WRAIR Announces COVID-19 Vaccine Candidate, Targets Clinical Trial Date

SpFN COVID-19 Clinical Trial

Clinical Trial NCT04784767: Phase 1 Study - SARS-COV-2-Spike-Ferritin-Nanoparticle (SpFN) Vaccine With ALFQ Adjuvant for Prevention of COVID-19 in Healthy Adults. This clinical protocol outlines a first-in-human study of the safety, tolerability, and immunogenicity of different doses of SpFN_1B-06-PL + ALFQ prophylactic vaccine against COVID-19 in healthy adults. The experimental vaccine in this study contains two parts: the vaccine (called SpFN_1B-06-PL) and an experimental adjuvant called ALFQ. An adjuvant is a substance added to vaccines that can help to make the vaccine more effective by improving the immune response or causing the immune response to last longer. The experimental vaccine in this study does not contain the virus and cannot cause you to become infected with the COVID-19 disease. A total of 72 healthy adult participants (18-55) will be enrolled in this study. Participants will be enrolled in one of three study arms. Principal Investigator: Paul Scott, M.D., MPHWalter Reed Army Institute of Research - Last Update Posted: September 14, 2021.

SpFN COVID-19 Preclinical Trial

SpFN was studied in nonhuman primates. 32 male and female specific-pathogen-free, research-naïve, Chinese-origin rhesus macaques (age 3 to 7 years) were distributed based on age, weight, and sex into four cohorts of 8 animals. Animals were vaccinated intramuscularly with either 50 or 5 μg of SpFN formulated with ALFQ or a placebo in the quadriceps muscle. Animals were vaccinated on alternating sides with each dose in the series. Immunizations were administered twice, four weeks apart, or once, four weeks before the challenge. Animals were challenged with 1x106 50% tissue culture infective dose (TCID50) of SARS-CoV-2 (SARS-Related Coronavirus 2, Isolate USA-WA1/2020) administered simultaneously by the intratracheal (1.0 ml) and intranasal (0.5 ml per nostril) routes.

The collective immune response elicited by SpFN translated into a robust and rapid reduction in replicating virus in the upper and lower airways of animals and resultant prevention of pulmonary pathology. Notably, SpFN protected against a potent viral challenge, as replicating virus concentrations detected in the upper and lower airways of unvaccinated controls reached a mean of 106 to 107 copies/ml. 

Clinical Trials

No clinical trials found