The World Health Organization has said at least 20 vaccines for coronavirus are in development around the world — though the process is likely to take many long months, as the medical world races to find both preventive measures and treatments for those infected.
“At least 20 vaccines are in development for COVID-19. Their first clinic trials are already starting,” Maria Van Kerkhove, head of the WHO’s emerging and infectious diseases unit, said Friday.
She cautioned that “We are still some time away before we would have a vaccine that could be used, and they still need to go through the trials for efficacy, but this work is under way.”
The head of WHO’s Health Emergencies Program, Dr. Mike Ryan, stressed that “There is only one thing more dangerous than a bad virus, and that’s a bad vaccine.
“We have to be very, very careful in developing any product that we are going to inject into potentially most of the world’s population.”
He added that China’s work on sequencing the genome of the virus before it became a global pandemic, and its sharing of that data, had helped work on vaccines around the world move much faster.
On Wednesday, The Times of Israel spoke with Dr. Ofer Levy, of Boston Children’s Hospital’s Precision Vaccines Program, whose team is one of the groups working on developing a vaccine, with a unique focus on a solution for the elderly.
Currently, there is no medicine specifically approved for treating COVID-19, the disease caused by the novel coronavirus, which has infected nearly 300,000 people worldwide and killed nearly 13,000 people.
Experts have warned against cutting corners, despite the virus’s unprecedented effect on the world, and have stressed the need to respect standard safety protocols.
“Governments are understandably desperate for anything that would forestall the deaths, closures and quarantines resulting from COVID-19,” Shibo Jiang, professor of virology at Shanghai’s University of Fudan and the New York Blood Center, wrote in the journal Nature this week.
“But combating this disease demands a vaccine that is safe and potent.”
Experts have warned that a vaccine could be more than a year away as clinical trials need to ensure it is safe in human test subjects before distributing to the wider public.
The president of the European Commission, Ursula von der Leyen, suggested Tuesday that regulatory approval for an eventual vaccine might be expedited.
“As we are under severe crisis, we’ll see that we are able to speed up any of the processes that are slow normally and take a lot of time and are very bureaucratic,” she said.
As some focus on inoculation, others are prioritizing treatment.
According to Benjamin Neuman, a virologist at Texas A&M University-Texarkana, immunizing against the pathogen is a long shot: There has never been a very successful human vaccine against any member of the coronavirus family.
“This is going to be a lot of trial, a lot of error, but we have a lot of options to try,” Neuman said.
Treatment could come sooner, with antiviral remdesivir showing early promise and already being used on an ad hoc basis before regulatory approval.
Remdesivir by the firm Gilead was developed to fight other viruses including Ebola (where it was shown to be ineffective) and it hasn’t yet been approved for treating anything. Still, it has shown early promise in treating some coronavirus patients in China, according to doctors, and manufacturer Gilead is moving ahead with final stage clinical trials in Asia. It has also been used to treat at least one US patient so far.
NIH’s Anthony Fauci, one of the top government scientists overseeing the coronavirus response, has said it could be available in the next “several months.”
Remdesivir gets modified inside the human body to become similar to one of the four building blocks of DNA, called nucleotides. Neuman told AFP that when viruses copy themselves, they do it “quickly and a bit sloppily,” meaning they might incorporate remdevisir into their structure — though human cells, which are more fastidious, won’t make the same mistake. If the virus incorporates the remdesivir into itself, the drug adds unwanted mutations that can destroy the virus.
Chloroquine and hydroxychloroquine
Israeli generic drug giant Teva announced Friday that it will provide 10 million doses of its anti-malarial drug hydroxychloroquine, which could potentially prove effective in fighting the coronavirus pandemic, to US hospitals free of charge.
US President Donald Trump touted the potential use of chloroquine on Thursday after encouraging results in China and France, although many experts warn of caution.
The hydroxychloroquine molecule, also used for decades in autoimmune diseases like lupus or rheumatoid arthritis, could indeed have an effect on the elimination of the virus, said Professor Didier Raoult, director of France’s Institut Hospitalo Universitaire (IHU) for the study of infectious diseases.
Toyama Chemical’s Favipiravir
This week Chinese authorities said a drug produced in Japan could be effective for treating coronavirus patients. China’s ministry of science and technology said late Tuesday that some clinical trials have been completed on favipiravir — the main ingredient in the influenza drug Avigan.
The trials using the drug as a treatment for COVID-19, the disease caused by the virus, showed “very good clinical results,” an official said.
A trial involving 80 cases conducted by a hospital in Shenzhen and a study of 120 cases led by Wuhan University’s Zhongnan Hospital both showed the drug shortened the recovery time for patients. Clinical tests using Avigan as a treatment for the virus have also started in Japan.
Within weeks of Chinese researchers making the genome of the virus public, a team at the University of Texas at Austin was able to create a replica model of its spike protein, the part which attaches to and infects human cells, and image it using a cryogenic (cooled) electron microscope.
This replica itself is now the basis for a vaccine candidate because it may provoke an immune response in the human body without causing harm — the classical method for developing vaccines based on principles dating back to smallpox vaccine in 1796.
NIH is also working with Moderna, a relatively new firm founded in 2010, to make a vaccine using the protein’s genetic information to grow it inside human muscle tissue, rather than having to inject it in. This information is stored in an intermediary transient substance called “messenger RNA” that carries genetic code from DNA to cells.
“The advantage is that it’s really fast,” explained Jason McLellan, who led the UT Austin team, whereas the traditional approach of creating the protein outside is difficult to scale and takes a long time.
The vaccine began its first human trial on March 16 after being proven effective in mice. If all goes to plan, it could be available on the market in about a year and a half, ready in case the coronavirus outbreak continues until the next flu season, according to Fauci.
Regeneron treatment and vaccine
Regeneron last year developed an intravenous drug that was shown to significantly boost survival rates among Ebola patients using what are known as “monoclonal antibodies.”
To do this, they genetically modified mice to give them human-like immune systems. The mice are exposed to viruses, or weakened forms of them, in order to produce human antibodies, Christos Kyratsous, the company’s vice president of research told AFP. These antibodies are then isolated and screened to find the most potent ones, which are grown in labs, purified and given to humans intravenously.
“If everything goes well, we should know what our best antibodies are within the next few weeks,” with human trials to begin by summer, said Kyratsous.
The drug could work as both a treatment and as a vaccine, by dosing up people before they are exposed — though these effects would be only temporary.
In the near term, they are also trying to repurpose another of their drugs devised using the same platform called Kevzara, which is approved to treat inflammation caused by arthritis. This could help fight the lung inflammation seen in the severe forms of the COVID-19 disease — in other words fighting a symptom as opposed to the virus itself.
The French drugmaker Sanofi is partnering with the US government to use a so-called recombinant DNA platform to produce a vaccine candidate. It takes the virus’ DNA and combines it with DNA from a harmless virus, creating a chimera that can provoke an immune response.
The antigens it produces can then be scaled up.
The technology is already the basis of Sanofi’s influenza vaccine, and believes it has a head start due to a SARS vaccine it developed that offered partial protection in animals. David Loew, the company’s head of vaccines, is reported to have said Sanofi expects to have a research candidate ready for lab testing within six months and for clinical study within a year and a half.
Inovio Pharmaceuticals vaccine
Inovio, another US biopharmaceutical, has since its founding in the 1980s worked on DNA vaccines — which work in a similar way to RNA vaccines explained above but work at an earlier link of the chain.
As an analogy, DNA can be thought of as a reference book in a library, while RNA is like a photocopy of a page from that book containing instructions to carry out a task.
“We plan to begin human clinical trials in the US in April and soon thereafter in China and South Korea, where the outbreak is impacting the most people,” said J. Joseph Kim, Inovio’s president and CEO in a statement.
“We plan on delivering one million doses by year end with existing resources and capacity.”
Other notable efforts
- British drugmaker GlaxoSmithKline has teamed up with a Chinese biotech firm, providing adjuvant platform technology. An adjuvant is added to some vaccines to enhance the immune response, thereby creating a stronger and longer lasting immunity against infections than the vaccine alone.
- Like Moderna, CureVac is working with the University of Queensland on a messenger RNA vaccine. Its CEO Daniel Menichella met with the White House earlier this month, and announced the company expects to have a candidate within a few months.
- American pharma Johnson & Johnson is looking at repurposing some of its existing drugs to see how they might help treat the symptoms of patients already infected with the virus. It’s also working on developing a vaccine involving a deactivated version of the pathogen.
- California-based Vir biotechnology has isolated antibodies from SARS survivors and is looking to see if these can treat the new coronavirus. Its platform has previously developed treatments for Ebola and other diseases.