FDA Revokes Authorization for the Only Remaining COVID-19 Monoclonal Antibody Treatment

The last remaining COVID-19 monoclonal antibody treatment, bebtelovimab, is no longer authorized for emergency use in the United States, the Food and Drug Administration announced last week.

Bebtelovimab does not appear to hold up against the Omicron subvariants BQ.1 and BQ.1.1, which make up more than 60% of COVID-19 cases nationally and are likely to continue gaining prevalence, the FDA said.

Eli Lilly, the manufacturer of bebtelovimab, has stopped distributing the antibody treatment, the FDA said. The U.S. government is keeping its stock of the treatment on-hand, in case it can be useful against future variants.

The evolution of COVID-19 has already rendered many monoclonal antibody treatments ineffective. The bebtelovimab news marks the removal of yet another tool from the arsenal to defend against COVID-19.

“It is not a surprising move. I think it’s a little bit overdue,” Jason Gallagher, PharmD, a clinical professor at Temple University School of Pharmacy and clinical pharmacy specialist in infectious diseases at Temple University Hospital, told Verywell. “We’ve reached the point where the majority of new COVID infections are due to strains that bebtelovimab doesn’t work against, so it was time to pull the plug.”

In a preprint study, researchers reported that Omicron BQ.1.1, BA.4.6, and BA.2.75.2 were all resistant to bebtelovimab. Neutralizing antibody levels were “low to undetectable” against BQ.1.1 four months after boosting.

There were more than 300,000 reported COVID-19 cases in the last week. With the approach of colder winter months, cases are expected to increase. Given the rapid evolution of the virus, future variants could become even more transmissible and evasive of our current treatments.

Fewer Options for Immunocompromised Patients

Bebtelovimab is a single-dose injection given to people who test positive for COVID-19 and are at high risk of developing severe disease. Before it was discontinued, the FDA said bebtelovimab should only be given to people who cannot take antiviral drugs like Paxlovid (nirmatrelvir and ritonavir) or remdesivir.

For people with weakened immune systems, monoclonal antibodies are preferable to antivirals, Gallagher said. Paxlovid, for instance, interacts with many medications that might be essential for immunocompromised people.

“It isn’t that Paxlovid or other antivirals won’t work in them. They certainly can. It’s just the most obvious deficit that patients have is the antibody response from vaccinations. We basically could give that to them as a monoclonal, but now we can’t,” Gallagher said.

What Other COVID-19 Treatments Are Available Now?

In addition to bebtelovimab, several monoclonal antibodies have already been discontinued because they were shown to fail at neutralizing the dominant Omicron subvariants:

• Bamlanivimab plus etesevimab from Eli Lilly
• Casirivimab plus imdevimab from Regeneron
• Sotrovimab from GSK
  

Paxlovid is the primary treatment that is considered to be effective against newer Omicron variants. The antiviral Lagevrio (molnupiravir) is also an oral medication.

Both Lagevrio and Paxlovid work by blocking the virus from replicating. While many treatments target the virus’ spike protein, these drugs target certain components of the virus that don’t change from variant to variant.

Remdesivir, sold under the name Veklury, can also slow the disease progression to keep people sick with COVID-19 out of the hospital. But it must be given intravenously over several days, making it an inconvenient option for most people.

Evusheld (tixagevimab plus cilgavimab) is a pre-exposure therapy that gives a boost to people who mount only a weak immune response from vaccination. The treatment is still available, though the FDA warned last month that it may not hold up against newer viral variants.

Immunocompromised individuals can also receive COVID-19 convalescent plasma. This treatment became less commonly used after monoclonal antibodies became available, but Gallagher said the medical community may have to consider using them again.

Gallagher said monoclonal antibodies are still worth investing in and manufacturers are working on developing monoclonal antibodies that will better target newer versions of Omicron.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.