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When it comes to creating treatments for Covid-19, the disease caused by the novel coronavirus, the first line of defense may be a century-old technology: purified blood plasma.

Medical literature published during the Spanish flu pandemic of 1918 includes case reports describing how transfusions of blood products obtained from survivors may have contributed to a 50% reduction in death among severely ill patients. In 1934, a measles outbreak at a Pennsylvania boarding school was halted when serum harvested from the first infected student was used to treat 62 fellow students. Only three of the 62 students developed measles — all mild cases.

More recently, plasma-derived therapy was used to treat patients during outbreaks of Ebola and avian flu. And on Wednesday the Japanese drugmaker Takeda Pharmaceutical Co. said it was developing a new coronavirus drug derived from the blood plasma of people who have recovered from Covid-19. Its approach is based on the idea that antibodies developed by recovered patients might strengthen the immune system of new patients.


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Here’s what you need to know about how this old technology might help slow the coronavirus outbreak.

How is blood plasma turned into an infection-fighting drug?

Patients who have recovered from a disease have permanent antibodies generated by the immune system floating in their blood plasma, the liquid component of blood. To turn that into a drug, the plasma is harvested, tested for safety, and purified to isolate those protective antibodies. When injected into a new patient, the “plasma-derived therapy” — also known as convalescent plasma — provides “passive immunity” until the patient’s immune system can generate its own antibodies.


Mike Ryan, the head of the WHO’s emergencies program, has said convalescent plasma is a “very important area to pursue” as a potential treatment for patients with Covid-19. “It must be given at the right time because it mops up the virus in the system and it just gives the new patient’s immune system a vital push at the time it needs it — but it has to be carefully time and it’s not always successful.”

Is this approach already being used in this outbreak?

In February, doctors in Shanghai set up a special clinical to administer convalescent plasma to select patients who were newly infected with coronavirus.

“In China, we’ve only heard anecdotal reports of encouraging results. Nothing has been published yet,” said Greg Poland, a physician and infectious disease expert at the Mayo Clinic in Rochester, Minn. “But this approach is definitely worth trying.”

How is what Takeda is doing different?

Takeda already makes a medicine called intravenous immunoglobin, or IVIG, for treating patients who have immune disorders. It consists of antibodies of all types purified from the blood plasma of healthy people. Giving antibodies in this purified form is easier, because it requires a much lower volume of treatment; it’s safer, because there is no chance of transmitting other viruses; and it’s more efficient.

With its new treatment, TAK-888, Takeda hopes to create an IVIG from the blood of people who have been infected with the coronavirus and who have recovered. That could create a treatment or prophylactic relatively quickly. It might not need to go through phase I studies to demonstrate basic safety, or larger phase III studies to demonstrate efficacy. That means the treatment could be available sooner.

The other advantage of this approach is that researchers don’t need to figure out which antibodies work best at fighting off the novel coronavirus. They basically import the entire disease-fighting army of antibodies from patients whose bodies have already won. The antibodies in TAK-888 will be more narrowly selected to target coronavirus than those in garden variety IVIG.

How much of this new drug can Takeda make?

“We are not looking at this as a therapy that everyone should go on,” Julie Kim, the president of Takeda’s blood plasma unit, told STAT. “This will be targeted to patients who have severe disease.”

Kim said the hope is that a single donor might provide enough IVIG for a single patient. But it’s also possible that IVIG derived from several people would be needed to treat each patient. Takeda won’t know until it has taken steps to learn how many antibodies are present in patients who have recovered, and what dose of TAK-888 appears necessary to be effective. Those measures, Takeda said, could be discovered without large-scale trials.

Kim said that she could not comment on precise timelines until Takeda has had discussions with regulators like the Food and Drug Administration.

Are there others working with antibody treatments?

Yes. Among them is Regeneron, which is working on a mix of manufactured antibodies to attack the coronavirus. Vir Biotechnology, another biotech firm, has said it will have a similar approach.

The IVIG approach Takeda is using is known as “polyclonal antibodies,” which means, simply, that there are a lot of different types of antibodies in the mix. But many biotech drugs are what are known as monoclonal antibodies, single antibodies that can be originally generated in mice and then manufactured in huge tanks of cells.

One reason to be optimistic is that Regeneron has pulled it off before, manufacturing a treatment composed of three different monoclonal antibodies that appears to have some effectiveness against the Ebola virus.

Geoffrey Porges, an analyst at the investment bank SVB Leerink, said in an interview he was “very impressed” with the speed at which Regeneron developed an Ebola treatment. He said that the novel coronavirus might be harder, because it is not clear what parts of the rapidly mutating virus antibodies should target. “But if anyone can figure this out, it’s Regeneron,” he said.

Don’t vaccines also work by creating antibodies?

Vaccines work by teaching the body to make its own antibodies to an infectious agent without a person ever becoming infected. This is why they are among the most powerful weapons in public health.

But Porges, who worked at Merck’s vaccine division in the 1990s, said he thinks that creating a vaccine might be harder than companies expect, because this new virus is just not well enough understood. “You kind of need to have some fundamental understanding of the immunology and the virus before you can develop a vaccine,” he said. “It’s not clear to me that we have that.”

Many companies, including the biotechnology firm Moderna and the large pharmaceutical companies Johnson & Johnson and Sanofi, are working hard to develop vaccines quickly.

So which of these approaches is better? 

That’s not the right question. Convalescent plasma, and then IVIG, could provide our first-line defense for people with Covid-19, especially those who are older and at much higher risk for complications. A monoclonal antibody drug could reach a greater number of patients. We also need antiviral drugs, such as remdesivir, being tested by Gilead Sciences. And a vaccine could do the most to slow or stop transmission.

“We need them all,” said Poland of the Mayo Clinic.

Andrew Joseph contributed reporting.

  • Hope that try to make medicine and vaccine . try it levels best and hope you can do it

  • How successful is the plasma treatment going to be if you take into account the fact that many (no exact numbers, just based on info from English papers in Asia) of those recovered patients get reinfected? How will that affect a plasma solution?

  • World needs MNTA’s technology STAT. MNTA, in interim analysis of their data, have already proven in phase 1/2 clinical study that IVIG can be made at least 24 times more potent than it’s current form. This means that a 1,000 mg of IVIG (1 dose) can be hypersialylated, using MNTA’s technology, and turned into 24 doses (43mg) of M254. So instead of having a 1 : 1 cure ratio as stated above there’s a potential of 1 : 24, and likely even more. Their scientists is currently testing lower doses.

    • IVIG is administered 8 hours or 2 to 5 days depending on dose use (1000-2000 mg/kg). M254 at 43-250 mg/kg is administered in less than 2 hours. It will likely have a sub cutaneous formulation at the lower dose. This means that it can be administered in much less time.

  • This is gold standard, brilliant application of well known immunology principles in order to treat a desease in an uncharted territory.I think Antibody or Immunoglobulin therapy is the ideal.given the virus impacts largely on cell mediated immunity.however polyvalent/pool plasma Ig of recovered patients will have arguably a better cure rate compared to mono-derived in theory,as it will cover larger number of epitopes.

  • Sure the blood plasma will work. So why are the Chinese trying to get all the so called cured using a blood serum back into quarantine for another 14 days?

  • The article seems to lack some reality about the difficulties of setting up plasma products. Requires an immense amount of collection and processing. This won’t be available for quite some time in my opinion.

    Biotest AG has an interesting approach using an IgM-enriched immunoglobulin that had some data in SARS patients.

    Can we please stop mentioning VIR? While they may seem genuine, seems quite the ploy to keep newsflow going with their upcoming IPO lockup and the stock boosted many fold by hype. It’s a preclinical project many months away from even a lead candidate!

    • It feels like cures for other diseases will come from this line of research. The mutations, etc..are very much like cancers and other pathogens. This may end up breaking open a new and fruitful pathway.

  • Hello
    Many thanks for the article!
    I wonder if there is any work using computer simulation to find out which drugs or chemicals are most effective against this virus (using known information about the virus). If there is then would it be quick to make such drugs for infected people to use?
    Thank you!

  • This is indeed encouraging. I hope funding and encouragement by our government keeps pace, and that such remedies can outrun this virus.

  • it makes more sense to collect the virus from the blood of infected patients, purify and inactivate it, and use it to immunize subjects at risk and medical personnel

    • Yaa it’s a good idea. But the virus’s genome undergoes mutation in a very firster rate so we cannot treat with the same

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