Mark Johnson, Milwaukee Journal Sentinel
A potential vaccine for COVID-19 has been developed and tested successfully in mice, researchers at University of Pittsburgh School of Medicine reported Thursday.
The announcement, more than three months into a pandemic that has killed 50,000 people and sickened almost 1 million, presents an urgent challenge to government regulators, who must weigh just how much to speed up the vaccine approval process.
Vaccines often take years to receive approval from the U.S. Food and Drug Administration. Yet on March 16 the first four healthy volunteers in Seattle received a different potential COVID-19 vaccine, made by a company called Moderna and administered in a small clinical trial at Kaiser Permanente Washington Health Research Institute.
While the vaccine being tested in Seattle uses a new, faster but untested technology, the one developed in Pittsburgh employs the same technique used in flu shots. The vaccine uses lab-made viral protein to build a person's immunity to the virus.
The scientists in Pittsburgh hope they won't be far behind the Seattle researchers in getting their vaccine into trials. Tests in mice found that the vaccine developed by the team in Pittsburgh spurred a wave of virus-fighting antibodies within two weeks.
"We'd like to get this into patients as soon as possible," said Andrea Gambotto, associate professor of surgery at the University of Pittsburgh School of Medicine and co-author of a paper announcing the vaccine in the journal EBioMedicine.
"We would like to think a month, give or take. Maybe two months. We just started the process," said co-author Louis D. Falo Jr., professor and chairman of the Department of Dermatology at the University of Pittsburgh. Their paper represents work by 11 other scientists, including two from Erasmus Medical Center in Rotterdam, the Netherlands.
The potential COVID-19 vaccine follows up on research Gambotto and Falo did back in December 2003 when they were poised to proceed to clinical trials with a vaccine for another coronavirus, Severe Acute Respiratory Syndrome. At the time, the journal Nature reported, "SARS vaccines speed toward clinic."
But the outbreak had already waned. The World Health Organization declared SARS contained in July 2003.
Funding for the SARS vaccine vanished.
"SARS CoV-2 is teaching us that it is important to react and (follow) all the way through," Gambotto said. "Yes, it was a mistake not to test the vaccine back then."
Other scientists have suggested that a vaccine for one coronavirus would likely have offered at least some protection from all of them.
The two researchers also previously developed a vaccine to treat Arabian camels for another coronavirus, Middle East Respiratory Syndrome (MERS). Like SARS and COVID-19, MERS jumped from animals to people, infecting almost 2,500 and killing just under 860 since its discovery in 2012.
Gambotto said they adapted techniques they had developed previously for coronaviruses to create one specifically designed for the virus that causes COVID-19; the process of translating their work for use on COVID-19 took the scientists just 10 to 12 days.
Gambotto and Falo said their potential COVID-19 vaccine would be delivered to the upper arm, but would not require a shot from a needle as the flu vaccine does.
Instead, the scientists have developed a finger-tip sized patch that contains 400 tiny needles, each just half of one millimeter. The two scientists compared the patch to a Band-Aid and said it would feel a lot like having Velcro pressed against the skin.
The needles, made from sugar and protein pieces, would penetrate the upper level of skin, absorb moisture from the skin and release molecules. The molecules would prompt the immune system to make antibodies that attack the virus.
The Pittsburgh researchers touted two advantages to the vaccine they call PittCoVacc.
Most important, the vaccine does not have to be frozen when stored or transported; it can sit at room temperature. That would make the vaccine much cheaper to deliver to poorer countries.
While the researchers could not say exactly how much a dose of the vaccine will cost, they estimated that the patch of needles used to deliver the vaccine would likely cost less than $10 a patch.
Also, the technique employing the tiny needles, releases a highly concentrated, much smaller amount of viral protein. The scientists said a single person would be able to make hundreds of vaccine patches a day.
The vaccine was developed without using the live virus that causes COVID-19. Scientists used DNA molecules made in the lab.
When released from the patch the vaccine, exploits the crucial part of the virus that latches onto human cells, the Spike protein.
The virus' Spike protein usually acts like a key opening up human cells and allowing the virus to invade. The vaccine acts a little like gum in a lock, preventing the key from working and keeping the virus from entering human cells.
Early in the pandemic health officials took pains to stress that a vaccine would probably take 18 months to develop, test and ready for human use. Whether or not the first vaccines will take that long to reach people is not known.
In the meantime, scientists have been working furiously to develop two possible treatment methods: the use of plasma from recovered COVID-19 patients; and use of drugs that have been found safe already for use in people, such as the anti-malarial drug chloroquine.
Hospitals have already begun using survivor plasma on a compassionate, experimental basis.
Posts
No comments:
Post a Comment