Many countries are investing a great deal of scientific effort in developing an effective and safe vaccine for the SARS-CoV-2 coronavirus. Recently, the United States, China and Chile announced promising vaccine candidates, but developing a vaccine is a long and complex process, and before that, each of these candidates will have to go through several phases before it is ready for administration.
Yesterday, we learned about the existence of a new possible vaccine against the COVID-19 disease, which also presents an innovative application method, and has many advantages in terms of mass manufacturing and storage.
It has been presented by scientists at the University of Pittsburgh School of Medicine and, according to the academic article in which they describe it published by The Lancet , it obtained promising results “after peer review”; that is, after the critical assessment tool of all research sent to scientific journals, and carried out by experts in that area who are not part of the study in question, endorsing it.
How does this prototype vaccine work?
Tested in mice (and this is important), the vaccine was administered through a patch the size of the tip of the index finger, and was able to produce antibodies specific for SARS-CoV-2 in amounts that were considered “sufficient to neutralize virus ” within two weeks after inoculation.
The publication, which can be read on EBioMedicine , also specifies that the researchers had previous experience with other coronavirus outbreaks: “We had prior knowledge of SARS-CoV (2003) and MERS-CoV (2012). These two coronaviruses, which are closely related to SARS-CoV-2, taught us that a particular protein, called a ‘spike’ protein, is important for inducing immunity against the virus. So we knew exactly where to start fighting this new virus, ”in the words of one of the lead authors, Andrea Gambotto, associate professor of surgery at the School of Medicine. And he adds: “That is why it is important to fund vaccine research. You never know where the next pandemic will come from.”
The vaccine candidate presented by China, and which has just started clinical trials, is based on messenger RNA (the coronavirus is made up of RNA, proteins and lipids). Instead, the new prototype described by the American researchers in Pittsburg (who they have precisely called PittCoVacc) uses ‘pieces’ of the spike proteins of the virus obtained in the laboratory to ‘build’ immunity , in a similar way to how the seasonal flu vaccines.
It is administered as a ‘strip’ of microneedles to the skin
Despite the similarities to the flu vaccine, these researchers have used a novel approach to administering the drug: it involves the microneedle array. This womb is a patch the size of the tip of the index finger. It involves 400 tiny needles that deliver the viral spike protein pieces into the skin, where the immune reaction is strongest. The patch is left in place like a plaster and then the needles simply dissolve into the skin because they are made of sugars.
Scientists say that this innovative form of administration would increase the potency of the vaccine. This would also make it a painless vaccine to administer. The administration system, according to the researchers, would be highly scalable, meaning that it can be easily manufactured in large quantities.
Advantages in mass production and warehousing
The vaccine ingredients, the protein pieces, are manufactured by a “cell factory”, a culture designed to express the spike protein of SARS-CoV-2. Meanwhile, the mass production of the microneedle array In addition, once manufactured, the vaccine can remain at room temperature until needed , eliminating the need for refrigeration during transport or storage.
Use in humans: when might it be available?
It is still too early to tell. At the moment, the animals that have been administered this vaccine protototype through microneedles have not yet been monitored in the long term, but the researchers indicate that they seem to follow the same trend as those that, in their day , generated antibodies against SARS: they produced sufficient immunity to neutralize the virus for at least a year.
Importantly, the PittCoVacc vaccine maintains its potency even after it has been fully sterilized with gamma radiation , a key step in making a product that is suitable for use in humans.
The authors are now in the process of applying for FDA approval, with the human clinical trial set to begin in the coming months.
The ‘negative’ part is that you will have to wait many months to have the vaccine available, as is the case with all the prototypes that have been developed. Once the clinical trial begins (for which there are still months), patient trials generally require at least a year.
More information: COVID-19 Vaccine Candidate Shows Promise
