‘Pan-coronavirus’ vaccine in development by US Army
A massive project aimed at developing a coronavirus vaccine that can provide protection against all SARS-CoV-2 variants is underway at the Walter Reed Army Institute of Research (WRAIR). Instead of focusing on a single permutation of the SARS-CoV-2 spike protein, as most first-wave COVID-19 vaccines have, WRAIR scientists chose to harness the unique structure of iron-carrying proteins to produce an array of different coronavirus antigens.
“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,” said Kayvon Modjarrad, from WRAIR’s Emerging Infectious Diseases Branch. “Our strategy has been to develop a ‘pan-coronavirus’ vaccine technology that could potentially offer safe, effective and durable protection against multiple coronavirus strains and species.”
Recently published studies outlined an innovative nanoparticle vaccine called SpFN, or the spike ferritin nanoparticle vaccine. Ferritin, an iron-based protein, has a unique structure that resembles a soccer ball with 24 different faces. Ferritin nanoparticles have been studied as a potential universal influenza vaccine because a different viral antigen can be attached to each of those 24 faces.
In the context of a coronavirus vaccine, scientists can attach a different spike protein to each of the 24 faces of a ferritin nanoparticle. This means a single nanoparticle could hold spikes from not only a variety of SARS-CoV-2 variants, but a variety of other common coronaviruses.
“This vaccine stands out in the COVID-19 vaccine landscape,” interjected Modjarrad. “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.”
A number of preclinical studies testing WRAIR’s SpFN vaccine in animals demonstrated robust immune responses against several SARS-CoV-2 variants – the most promising of these studies reported extraordinarily broad neutralising antibody responses in nonhuman primates against a variety of SARS-CoV-2 variants as well as effective immune responses against the original SARS virus from 2002.
Modjarrad has indicated the research team will be testing the effect of vaccine-induced antibodies against all known circulating SARS-CoV-2 variants, including Omicron. The researchers are also working on a trial looking at the safety of the vaccine in those previously vaccinated with a current COVID-19 vaccine, and in those who have previously been infected with the virus.
Read: EXCLUSIVE: Vaccine development made easy with single-use bioprocessing systems
Category: Features, Pharmaceuticals
