This story was updated April 29, 2020, with Oxford University saying it hopes to have its vaccine ready by September.
April 24, 2020 -- The race to find a vaccine for COVID-19 is on.
At least 90 potential COVID-19 vaccines are under study, and six of those are already being tested on humans in phase I clinical trials to determine if they’re safe. One vaccine, under development by a Chinese biotech company, just launched its phase II trial, which evaluates not only safety but also how well it works.
Oxford University launched its phase I/II clinical trial in late April, giving volunteers a vaccine derived from a cold virus from chimpanzees weakened and modified with SARS-CoV-2 proteins so that it doesn’t cause infection but can stimulate the immune system. One of the scientists working on the vaccine told CBS News that she hopes it will be available by September. According to a story in Business Insider, a drug company in India says it will start production on the vaccine to have it available then, even though it's not yet known whether it works.
That speed is incredible given that the genetic sequence of SARS-CoV-2, the coronavirus that causes COVID-19, was first published in mid-January. It set off a mad scramble among scientists to develop a vaccine to combat the deadly virus. Some experts believe the world won’t able to totally relax social distancing guidelines until a vaccine is available.
While it all sounds promising, a vaccine -- or vaccines -- will not be on the market anytime soon, experts caution. But some experts predict we’ll have one as soon as 9 months for possible emergency use.
Anthony Fauci, MD, a member of the White House coronavirus task force and director of the National Institute of Allergy and Infectious Diseases, has often cited a possible 12- to 18-month timeline.
And that is probably extremely optimistic, says Paul Offit, MD, director of the Vaccine Education Center and attending physician in the Division of Infectious Diseases at Children's Hospital of Philadelphia. "I don't see how 12 to 18 months is possible," he says. "That is ridiculously fast."
Vaccines may not make it past early stages of development if they don’t produce the desired immune response. Even if the vaccine proves safe, Offit says they are tricky to make. Once a drug maker has to scale up production, they have to ensure the vaccines are consistent from batch to batch so they will confer immunity across the board.
Traditionally, vaccines have cost over a billion dollars and take 10 to 15 years to get to market, says Litjen (L.J.) Tan, PhD, MS, chief strategy officer for the Immunization Action Coalition, a nonprofit that works to increase immunization rates.
Still, Offit says, "There are a lot of reasons for hope." Among them:
- Plenty of funding for development
- A range of approaches are under study
- New ways to approach clinical trials that can speed development
- Collaborations between small biotech firms developing the vaccines and large pharmaceutical companies, who have the capability of mass production.
The Short List
Among the vaccine projects that are most often cited as promising by vaccine experts:
mRNA Vaccine: This phase I trial started in mid-March. As of mid-April, three different doses have been given to three groups of 45 healthy adults, ages 18 to 55. An additional six groups, with three groups of older adults ages 56 to 70 and three groups of adults ages 71 and above, have been added to this phase I study. No preliminary results are yet available, says Colleen Hussey, a company spokesperson.
The vaccine uses something called the messenger RNA approach. It does not require a virus to make the vaccine.
Scientists identified the sequence for a key protein on the surface of the SARS virus, called a spike protein. This protein is key for allowing the virus to enter cells when a person gets infected. The instructions for making that spike protein were encoded into an instruction molecule called mRNA. When the vaccine containing the instruction molecule is injected, it travels to immune cells and triggers them to make copies of the spike protein as if the cells have been infected with the coronavirus. Other cells of the immune system then learn about the spike protein and can offer immunity if they come in contact with the coronavirus.
"I am very enamored by the mRNA technique," Tan says.
If early vaccine testing proves that it’s safe, developer Moderna says it intends to begin a phase II study, designed to look at effectiveness, in the second quarter of 2020. The company has federal funding of up to $483 million from the Biomedical Advanced Research and Development Authority (BARDA) within the U.S. Department of Health and Human Services. The biotech company is collaborating with the National Institutes of Health.
DNA Vaccine: Phase I clinical trials have begun on a DNA vaccine from INOVIO. The technology uses DNA designed to produce a specific immune response. A hand-held smart device that uses a brief electrical pulse to open small pores in the skin delivers the vaccine. When the DNA is inside a cell, it instructs the cell to produce many copies of the artificial DNA, stimulating the body's natural response.
The first patient was enrolled in early April. Up to 40 healthy adults are scheduled to be enrolled.
The company is partnering with the International Vaccine Institute and the Korea National Institute of Health and has $6.9 million in funding from the Coalition for Epidemic Preparedness Innovations (CEPI). Initial results on safety and response are expected by late summer.
Adenovirus Vaccines: University of Oxford scientists are launching the phase I/II clinical trial of its vaccine made from a weakened version of a common cold virus, the adenovirus, taken from chimpanzees. The adenovirus is genetically altered so it's incapable of reproducing itself. The vaccine is combined with genes to trigger antibodies that allow the immune system to destroy the virus. That type of clinical trial allows researchers to test safety and how well it works at the same time.
CanSino Biologics in Tianjin, China, has just launched phase II of its study for its recombinant novel coronavirus vaccine, using a type of adenovirus known as Ad-5. Researchers plan to enroll 500 people.
Approaches to Speed Development
One approach to clinical trials that could help speed vaccine development is known as adaptive design trials, according to Peter Marks, MD, PhD, director of the Center for Biologics Evaluation and Research at the FDA. That could mean looking at ''real time'' data from a trial as it comes in, using that data to modify the study according to preset rules.
The FDA could also make use of its Emergency Use Authorization powers, which permits the FDA Commissioner to allow use of an unapproved medical product, such as a vaccine, when no other product is available. "Whether we could or couldn't would depend on the evidence we saw," Marks says, in addition to evaluating ''the situation on the ground" at that time with the pandemic.
FDA is already reassigning staff to deal with the incoming information on vaccines in development, Marks says.
Perspectives on the Race
"It's hard to predict which [vaccines] will be the ones that will prevail," says Maria Elena Bottazzi, PhD, co-director of the Texas Children's Center for Vaccine Development at Baylor College of Medicine, Houston.
As much as the newer technologies may have theoretical advantages, she believes a vaccine must be globally accessible and affordable.
"We want a vaccine for the world," she says, not only for the countries affluent enough to pay for the more expensive vaccines. "We should evaluate a huge portfolio [of vaccines] that include sophisticated technology but not shut the door on those that may not sound innovative [because they are based on older technologies]."
"This is a pandemic, and more than a pandemic, it's a pandemic with a really high penalty," says David B. Weiner, PhD, executive vice president and director of the Vaccine & Immunotherapy Center at Wistar Institute, which focuses on research in infectious disease, cancer, and immunology. It's not just the deaths, he says, but the serious illness. "We haven't seen these kinds of penalties in a long time, so that changes the equation." It underscores the need for thinking in new ways, he says. If emergency use is allowed, it may permit researchers to test a lower number of people in the safety phase, for instance, to allow the researchers to collect that additional safety data as they also deploy the vaccine, he says.
"There is going to be a lot of people pushing for innovation in vaccine trials," he says, while preserving safety, to get to the goal.