Recovered victims’ blood may hold key
Biotech firms amass samples in race to test antibodies’ effect
In the race to develop treatments for the coronavirus, two California biotech companies are teaming up to collect blood samples from people who have recovered from COVID19 — with the hope that antibodies produced by their immune system after being infected can provide the key to developing a drug or vaccine.
San Francisco’s Vir Biotechnology and Los Angeles’ Sanguine Biosciences have begun collecting blood samples from 100 recovered patients in the Bay Area, Los Angeles, San Diego, Seattle, Boston and Washington, D.C. Patients must have had a case of COVID19, the disease caused by the virus, confirmed by a diagnostic test to participate in the study, and their diagnosis
“We want to definitely investigate the possibility antibodies can be used as a therapeutic.”
Dr. Robert Siegel, infectiousdisease specialist at Stanford
must have been made at least two weeks prior to their blood being drawn for the study.
The study is part of a growing number of investigations by researchers at drug companies, universities and public health agencies striving to better understand antibodies associated with the coronavirus. The idea is to not only create tests to detect who has had the virus, but also develop drugs to treat those who are sick.
When a person contracts a virus, the body produces millions of antibodies that circulate in the blood to fight the infection. The best candidates for a drug are antibodies that “neutralize” a virus by binding the most strongly to it and prevent it from infecting cells. For the virus behind COVID
19, researchers believe the antibody that holds the most promise would bind to the spiky, crownlike protein that gives the coronavirus its name.
Vir, a 3yearold immunology company, has previously identified antibodies that fight the viruses that cause hepatitis B and the flu, and those drugs are undergoing clinical trials. In late March, the company announced it identified two antibodies that neutralize SARSCoV2, the specific coronavirus that causes COVID19, in lab experiments. Vir is now working with the pharmaceutical company GlaxoSmithKline to conduct clinical trials in people over the next three to five months. The study with Sanguine is attempting to identify additional antibodies.
Sanguine is sending phlebotomists to recovered patients’ homes to conduct blood draws, while Vir is conducting the research.
The main way antibodies are useful in infectious disease outbreaks is in an antibody test — a blood test that shows if someone has had the virus and may be immune. But in cases like COVID19 where there is no effective treatment beyond anecdotal evidence — some doctors say drugs for malaria, Ebola and rheumatoid arthritis have appeared to help some of their patients’ symptoms improve — it’s important to look into whether antibodies can be used to treat the sick, too.
“Right now we don’t have any effective therapeutics (for COVID19), so we want look at everything,” said Dr. Robert Siegel, an infectiousdisease specialist at Stanford. “We want to definitely investigate the possibility antibodies can be used as a therapeutic.”
Antibody therapy has worked in a number of diseases, but the only viral disease it has worked for is respiratory syncytial virus, or RSV. And it has generated disappointing results in other diseases, such as Ebola. But antibodies have been used with some success to lessen the severity of symptoms after exposure to the rabies, hepatitis B and chickenpox viruses.
“There are no viral infections where we can throw antibodies at the person and they work magically,” Siegel said. “We don’t have any ex amples where that’s a home run.”
That is in part because antibodies are just one part of the human immune system. The other, the T cell response, is harder to measure and understand, but may play a more important role than antibodies in some diseases.
An antibody therapy, which would likely be an injectable drug, could help sick patients recover or provide temporary resistance in patients who have recovered.
“It is becoming increasingly clear that multiple therapeutic approaches, used in combination or in sequence, will be necessary to stop this coronavirus pandemic,” Vir’s chief executive, George Scangos, said in a statement.
“Everyone has an interest in making this happen as quickly as possible,” Scangos said in a January interview with The Chronicle in which he discussed the company’s efforts to develop a therapeutic using antibodies, but noted the challenges in moving quickly and safely.
“There are a number of things you have to find out, and you have to test it in some people to see if it works,” he said. “Before you expose a million people to it, you better be sure it’s safe.”
“Multiple therapeutic approaches ... will be necessary to stop this coronavirus pandemic.”
George Scangos, chief executive of Vir Biotechnolog y