Roche Holding AG became the latest company to win emergency US approval for a coronavirus antibody test and promised a fast scale-up of the tool that policy makers hope will smooth the reopening of economies.
The Swiss giant expects production of the test to reach the high double-digit millions by June and pass the 100 million monthly threshold later this year. The test looks for antibodies in blood that have been raised to fight off the virus that causes Covid-19.
Roche's version runs on a high-volume instrument that can produce a single result in 18 minutes and as many as 300 results in an hour, the company said in a statement Sunday after receiving emergency authorization from the U.S. Food and Drug Administration.
"Our people have been working in operations day and night to make sure we have all the products," Thomas Schinecker, head of Roche's diagnostics unit, said in a phone interview.
Antibody testing could help pinpoint which people have already been exposed to the virus, potentially giving them some immunity to it. It could also help determine how widely the disease has spread, since the molecular testing that's been around since January - and used to confirm more than 3 million infections globally - can't show who had the disease weeks or months ago.
While it's still unclear how strong immunity will be for different people - or how long it will last - knowing who has already fought off the virus could nonetheless show how vulnerable regions are to future outbreak waves. The pandemic probably won't be controlled until about two-thirds of the world's population is immune, according to a report from the Center for Infectious Disease Research and Policy at the University of Minnesota.
Antibody test
Roche's antibody test has demonstrated a "specificity" of more than 99.8% and a "sensitivity" of 100% when validated against over 5,000 blood samples taken from people 14 days after their Covid-19 cases were confirmed using molecular testing, Roche said.
If a test can reliably identify positive samples, it's considered highly sensitive. If it can identify negatives, it's called specific. That means it knows the difference between Covid-19 antibodies and others raised by, say, another coronavirus that causes the common cold.
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Governments are trying to learn how many people have been exposed to the virus as they wind down social-distancing measures. The restrictions on businesses have cost millions their jobs and the global economy is on course for its deepest dive since the Great Depression.
Countries including the U.K. and parts of the U.S. were so eager for antibody tests early on that they bought versions that didn't work. Most of the earliest versions on the market came from small players, but now bigger companies with strong reputations are bringing out their own versions - including Roche and Abbott Laboratories. The U.S. FDA has granted emergency use approval to about a dozen of these tests.
Roche's test is also cleared for countries accepting Europe's CE marking, the company said.
'Immunity passport'
With no vaccine available yet for the novel coronavirus, there have been proposals that people who have antibodies could be issued an "immunity passport" that would allow them to travel or return to work, on the assumption that they're safe from re-infection. Yet the World Health Organization has cautioned on the level of protection against a second infection that people who have recovered from Covid-19 will have.
In addition to the search for a vaccine, more than 100 different programs have been launched to develop and test treatments. These include everything from antiviral drugs and antibody-containing plasma from recovered patients, to traditional Chinese herbal medicine.
Gilead Sciences Inc.'s antiviral drug remdesivir has been cleared by US regulators for emergency use in Covid-19 patients, becoming the first medication backed by early clinical data to be made available to fight the disease.
Once any resistance to the coronavirus is better understood, Roche's new test could help assess who has built up immunity, Roche said. For now, the tests will probably go first to health-care workers and their families, along with people who have already had the disease and those who think they may have had it, Schinecker said.
"There are people that think they had the flu in February, and now they're not sure - did they have the flu or something else?" Schinecker said. "Most likely these people will be tested, and then over time you can see how this develops - are they immune, or are they not immune?"
