On April 2, 2020, researchers from the University of Pittsburgh (Pitt) School of Medicine announced that they may have a vaccine to combat SARS-CoV-2, which is the novel coronavirus causing the COVID-19 disease pandemic.
The scientists tested the vaccine in mice, using a small patch as the delivery system. They found that the mice produced enough SARS-CoV-2 antibodies to combat the disease. According to the co-senior author and associate professor of surgery at the Pitt School of Medicine, Dr. Andrea Gambotto, says, “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. That's why it's important to fund vaccine research. You never know where the next pandemic will come from."
The researchers refer to their vaccine as PittCoVacc, and they used a new approach for delivering the vaccine through what’s called a microneedle array, which is supposed to increase the potency of the vaccine. This array is a patch that has 400 tiny needles that deliver the spike protein pieces into the skin. The patch is like a band-aid. The needles, which are made of pieces of sugar and protein, dissolve into the patient’s skin.
Co-senior author and professor and chair of dermatology at Pitt’s School of Medicine, Dr. Louis Falo, says, “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. And it's actually pretty painless -- it feels kind of like Velcro."
The protein pieces are manufactured by using a cell factory, which is multiple layers of cultured cells that are engineered to express the SARS spike protein. Further stacking of cells can produce more yield. The other great thing about this vaccine is that it doesn’t require refrigeration. The vaccine can sit at ambient temperature until it’s needed.
The study authors are now applying to begin phase I human clinical trials within the next few months. "Testing in patients would typically require at least a year and probably longer," 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."
The results of the study are published in EBioMedicine.