The US biotech firm Eli Lilly on Wednesday announced it was seeking an emergency use authorization (EUA) for its lab-produced antibody treatments against Covid-19, after early trial results showed they reduced viral load, symptoms and hospitalization rates.
“Our teams have worked tirelessly the last seven months to discover and develop these potential antibody treatments,” said Daniel Skovronsky, Lilly’s chief scientific officer.
“Lilly is diligently working with regulators around the world to make these treatments available,” he added.
The company said in a statement that its “combination therapy” of two antibodies working together was shown to be effective in a placebo-controlled study of 268 patients with mild to moderate Covid-19.
Their analysis showed the proportion of patients with high viral load at day 7 of their illness was 3.0 percent on the therapy, compared to 20.8 percent on the placebo arm.
Improvement in symptoms was seen as early as three days after dosing.
The rate of Covid-related hospitalization and emergency visits was 0.9 percent for patients treated with combination therapy versus placebo 5.8 percent on placebo, a relative risk reduction of 84.5 percent.
The company is also studying a “monotherapy” of just one of the two antibodies, and said that parallel research showed that this was similarly effective.
The trial is ongoing and Lilly wants to recruit a total of 800 people.
Lilly said it expects to have 100,000 doses of the monotherapy available this month, and a million by the end of the year. It also expects to have 50,000 doses of the combination therapy by the end of 2020.
The findings have not yet been published in a peer-reviewed journal.
Both antibodies work by binding to different parts of spike proteins on the surface of the SARS-CoV-2 virus, distorting their structure so the virus can’t invade living cells.
Antibodies are infection-fighting proteins made by the immune system and can also be harvested from recovered patients, but it is not possible to make so-called “convalescent plasma” a mass treatment.
Researchers can also comb through the antibodies produced by recovered patients and select the most effective out of thousands, and then manufacture them at scale.
US President Donald Trump, who has Covid-19, received a dose of synthetic antibodies produced by the firm Regeneron last week.
Regeneron has also reported encouraging results from its early trials, but hasn’t yet applied for emergency approval and so remains an experimental treatment.
The US Food and Drug Administration has previously granted an EUA for the antiviral remdesivir, for convalescent plasma, and for hydroxychloroquine, which was subsequently revoked over safety fears.
In addition, US health authority’s guidelines recommend the use of the steroid dexamethasone to control a damaging inflammatory response seen in later stages of Covid-19.