by Elizabeth Hofheinz, M.P.H., M.Ed., April 3, 2020
In what is a much-needed ray of sunshine, on April 2, 2020 scientists from the University of Pittsburgh School of Medicine announced a potential vaccine against SARS-CoV-2, the new coronavirus (COVID19).
Their paper is published in EBioMedicine, which is published by The Lancet, and is the first study to be published after critique from fellow scientists at outside institutions that describes a candidate vaccine for COVID-19. “Pitt” says that its researchers were able to act quickly because they had already laid the groundwork during earlier coronavirus epidemics.
“We had previous experience on SARS-CoV in 2003 and MERS-CoV in 2014. These two viruses, which are closely related to SARS-CoV-2, teach us that a particular protein, called a spike protein, is important for inducing immunity against the virus. We knew exactly where to fight this new virus,” said co-senior author Andrea Gambotto, M.D., associate professor of surgery at the Pitt School of Medicine. “That’s why it’s important to fund vaccine research. You never know where the next pandemic will come from.”
“Our ability to rapidly develop this vaccine was a result of scientists with expertise in diverse areas of research working together with a common goal,” said co-senior author Louis Falo, M.D., Ph.D., professor and chair of dermatology at Pitt’s School of Medicine and UPMC.
Describing this dissolvable microneedle array, Dr. Falo said in a video, “…What the microneedle array is able to do is deliver the vaccine antigen directly into those areas of the skin that are made to make the immune response so it results in a very potent vaccine…think about them almost like a BandAid, so the microneedle array is simply applied to the skin topically pressed into place very shortly and then it is taken off and thrown away and then the antigen is already delivered.”
As stated in the news release, “Compared to the experimental mRNA vaccine candidate that just entered clinical trials, the vaccine described in this paper — which the authors are calling PittCoVacc, short for Pittsburgh Coronavirus Vaccine — follows a more established approach, using lab-made pieces of viral protein to build immunity. It’s the same way the current flu shots work.”
“We developed this to build on the original scratch method used to deliver the smallpox vaccine to the skin, but as a high-tech version that is more efficient and reproducible patient to patient,” Falo said. “And it’s actually pretty painless — it feels kind of like Velcro.”
According to the news release, “The system also is highly scalable. The protein pieces are manufactured by a “cell factory” — layers upon layers of cultured cells engineered to express the SARS-CoV-2 spike protein — that can be stacked further to multiply yield. Purifying the protein also can be done at industrial scale. Mass-producing the microneedle array involves spinning down the protein-sugar mixture into a mold using a centrifuge. Once manufactured, the vaccine can sit at room temperature until it’s needed, eliminating the need for refrigeration during transport or storage. When tested in mice, PittCoVacc generated a surge of antibodies against SARS-CoV-2 within two weeks of the microneedle prick.”
“Those animals haven’t been tracked long term yet, but the researchers point out that mice who got their MERS-CoV vaccine produced a sufficient level of antibodies to neutralize the virus for at least a year, and so far the antibody levels of the SARS-CoV-2 vaccinated animals seem to be following the same trend.”
“Importantly, the SARS-CoV-2 microneedle vaccine maintains its potency even after being thoroughly sterilized with gamma radiation — a key step toward making a product that’s suitable for use in humans. The authors are now in the process of applying for an investigational new drug approval from the FDA in anticipation of starting a phase I human clinical trial in the next few months.”
“Testing in patients would typically require at least a year and probably longer,” Dr. Falo said. “This particular situation is different from anything we’ve ever seen, so we don’t know how long the clinical development process will take. Recently announced revisions to the normal processes suggest we may be able to advance this faster.”