Companies test antibody drugs to treat, prevent COVID-19
With a coronavirus vaccine still months off, companies are rushing to test what could be the next most sensible thing: drugs that deliver antibodies to fight the virus immediately, and never have to train the disease fighting capability to make them.
Antibodies are proteins your body makes when contamination occurs; they attach to a virus and make it be eliminated. Vaccines work by tricking the body into thinking there’s contamination so that it makes antibodies and remembers how to do that if the true bug turns up.
But it can take per month or two after vaccination or infection for the very best antibodies to create. The experimental drugs shortcut that process giving concentrated versions of specific kinds that worked best against the coronavirus in lab and animal tests.
“A vaccine does take time to work, to force the development of antibodies. However when you give an antibody, you get immediate protection,” said University of NEW YORK virologist Dr Myron Cohen. “If we are able to generate them in large concentrations, in big vats within an antibody factory ... we are able to sort of bypass the immune system.”
These drugs are thought to last for per month or more and may give quick, non permanent immunity to persons at risky of infection, such as health employees and housemates of someone with COVID-19. If they proved effective and if a vaccine doesn't materialize or protect as hoped, the drugs might eventually be looked at for wider use, perhaps for teachers or other groups.
They’re also being tested as treatments, to greatly help the immune system and stop serious symptoms or death.
“The hope there is to target persons who are in the first week of their illness and that people can treat them with the antibody and stop them from getting sick,” said Dr Marshall Lyon, an infectious disease expert helping to test one particular drug at Emory University in Atlanta.
Having such an instrument “would be a really momentous part of our fight against COVID,” Cohen said.
Vaccines have emerged as an integral to controlling the virus, which includes been confirmed to have infected a lot more than 20 million persons worldwide and killed a lot more than 738,000. Several companies are racing to build up vaccines, however the results of the large final tests had a need to evaluate them are months away.
The antibody drugs are “very promising” and, on the other hand, could possibly be available “fairly soon," said Dr Janet Woodcock, a U.S. Food and Drug Administration official who's leading government efforts to speed COVID-19 therapies. Key studies are underway and some answers should come by early fall.
One company, Eli Lilly, has recently started manufacturing its antibody drug, betting that studies now underway will give positive results.
“Our goal is to get something out as quickly as possible” also to have thousands of doses ready by fall, said Lilly’s chief scientific officer, Dr Daniel Skovronsky.
Another company that developed an antibody drug cocktail against Ebola - Regeneron Pharmaceuticals Inc. - now is testing one for coronavirus.
“The success with this Ebola program gives us some confidence that people can potentially do that again,” said Christos Kyratsous, a Regeneron microbiologist who helped lead that work.
Regeneron’s drug uses two antibodies to improve chances the drug will work whether or not the virus evolves to evade action by one.
Lilly is testing two different, single-antibody drugs - one with the Canadian company AbCellera and another with a Chinese company, Junshi Biosciences. In July, Junshi said no safety concerns emerged in 40 healthy persons who tried it and that larger studies were getting underway.
Others working on antibody drugs include Amgen and Adaptive Biotechnologies. The Singapore biotech company Tychan Pte Ltd. is testing an antibody drug and has similar products in development for Zika virus and yellow fever.
“I’m cautiously optimistic” about the drugs, said the country's top infectious diseases expert, Dr Anthony Fauci. “I’m heartened by the knowledge that we had with Ebola,” where the drugs proved effective.
What could go wrong?
- The antibodies might not exactly reach all the places within the body where they have to act, such as for example deep in the lungs. All of the antibody drugs receive via an IV and must make their way through the bloodstream to wherever they’re needed.
- The virus might mutate in order to avoid the antibody - the reason Regeneron is testing a two-antibody combo that binds to the virus in several places to help prevent its escape.
Skovronsky said Lilly stuck with one antibody because manufacturing capacity would essentially be cut in two to make two, and “you should have less doses available.” If a single antibody works, “we are able to treat doubly many people,” he said.
- The antibodies might not last long enough. If indeed they fade within a month, it’s still OK for treatment since COVID-19 illness usually resolves for the reason that time. But for prevention, it might not be practical to give infusions more regularly than on a monthly basis or two.
A SAN FRANCISCO BAY AREA company, Vir Biotechnology Inc., says it has engineered antibodies to last longer than they usually do to avoid this issue. GlaxoSmithKline has invested $250 million in Vir to check them.
Giving a higher dose also can help. If half of antibodies disappear after a month, “if you give twice as much, you should have two months’ protection,” Lilly’s Skovronsky said.
- The big fear: Antibodies may do the contrary of what’s hoped and also enhance the virus’s ability to enter cells or stimulate the immune system in a way that makes persons sicker. It’s a theoretical concern that hasn’t been observed in testing up to now, but large, definitive experiments are had a need to prove safety.
Source: japantoday.com
