Scientists have identified a potential vaccine against SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic, that is proven effective in mice.
The Pittsburgh Coronavirus Vaccine, PittCoVacc, is the first candidate vaccine to be peer-reviewed and published – today in EBioMedicine, published by The Lancet – and works in the same way as flu shots, putting it forward as a “promising” strategy to immunize against coronavirus infection. When tested in mice, PittCoVacc generates a surge of antibodies against SARS-CoV-2 within just two weeks that are believed to be sufficient at neutralizing the virus.
It is delivered using a microneedle array to increase potency. A finger-tip sized patch with 400 tiny needles is applied directly to the skin – which is where immune reaction is the strongest – and goes on like a Band-Aid. Each needle is made of sugar and protein pieces that dissolve into the skin.
“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," said co-senior author Louis Falo, MD, PhD, professor and chair of dermatology at Pitt's School of Medicine and UPMC in a statement. "And it's actually pretty painless – it feels kind of like Velcro.”
The vaccination was created four weeks after scientists were able to successfully sequence SARS-CoV-2. Researchers at the University of Pittsburgh School of Medicine were able to move quickly because they had laid the groundwork for a vaccine during earlier coronavirus epidemics, like the Severe Acute Respiratory Syndrome (SARS) outbreak in 2003 and the Middle East Respiratory Syndrome (MERS) epidemic nine years later.
"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, MD, associate professor of surgery, in a statement. "That's why it's important to fund vaccine research. You never know where the next pandemic will come from."
In both SARS and MERS, the spike protein (S protein) is crucial for viral transmission and infection. The researchers say that PittCoVacc is different than an experimental vaccination mRNA-1273 currently in Phase 1 clinical testing and is largely scalable in the way that it can be mass-produced at an industrial level. Once manufactured, the vaccine can sit at room temperature until it’s needed and does not require a needle for administration.
"For most vaccines, you don't need to address scalability to begin with," said Gambotto. "But when you try to develop a vaccine quickly against a pandemic that's the first requirement."
The team will be applying for an investigational new drug approval from the US Food and Drug Administration to start human clinical trials in the next few months – but this is just the beginning. Vaccination testing and approval can take several months to years to receive approval.
"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."