Monoclonal antibodies: Highest-risk COVID patients are least likely to get effective treatment, Harvard researchers say

"Monoclonal antibodies should first go to patients at the highest risk of death from COVID-19, but the opposite happened -- the healthiest patients were the most likely to get treatment."

People who are at the highest risk for severe COVID-19 are often least likely to get monoclonal antibodies to fight an infection, according to Harvard researchers in a new study.

Monoclonal antibodies are very effective at treating mild to moderate COVID-19 cases among non-hospitalized patients. But during the pandemic, monoclonal antibodies have been in short supply.

Federal guidelines prioritize patients at higher risk of being hospitalized or dying from COVID-19, including older people and those with chronic conditions. But the researchers from Harvard T.H. Chan School of Public Health discovered that people 65 or over, who are at the highest risk for severe COVID-19, have often been the least likely to receive the antibodies.

“Monoclonal antibodies should first go to patients at the highest risk of death from COVID-19, but the opposite happened — the healthiest patients were the most likely to get treatment,” said Michael Barnett, assistant professor of health policy and management at Harvard Chan School and lead author of the study.

“Unfortunately, our federal and state system for distributing these drugs has failed our most vulnerable patients,” Barnett said.

The researchers wanted to learn how the limited supply of the therapy was allocated to patients at highest risk for severe disease. They looked at data from more than 1.9 million Medicare beneficiaries who had been diagnosed with COVID-19 between November 2020 and August 2021 — and compared rates of receiving monoclonal antibodies by age, sex, race and ethnicity, region and number of chronic conditions.

Among Medicare beneficiaries who weren’t hospitalized or who didn’t die within seven days of their diagnosis, only 7.2% received monoclonal therapy.

The likelihood of receiving the antibodies was higher among those with fewer chronic conditions — 23.2% of those with no chronic conditions received the therapy, versus 6.3%, 6.0% and 4.7% of those with one to three chronic conditions, four to five chronic conditions, and six or more chronic conditions, respectively.

The researchers also found that Black individuals were less likely to receive the therapy than white individuals — 6.2% versus 7.4%.

The researchers speculated as to why the therapy often failed to reach the highest-risk COVID-19 patients. They said it’s possible that higher-risk patients may have had a tough time navigating the multiple steps needed to receive monoclonal antibodies, from receiving a timely diagnosis to referral and scheduling an infusion within 10 days.

“We need new approaches to prevent these inequities from happening again with newer treatments on the horizon,” Barnett said.

There were also major differences among states when it came to the treatment. Rhode Island and Louisiana administered monoclonal antibodies to the highest proportion of nonhospitalized patients with COVID-19 (24.9% and 21.2%), while Alaska and Washington administered the lowest proportion (1.1% and 0.7%).

Southern states had the highest rates of the therapy (10.6% of beneficiaries), while states in the west had the lowest rates (2.9%).

Amid the omicron surge, the FDA decided to unauthorize two monoclonal antibody treatments because data shows that these treatments are highly unlikely to be effective against the omicron variant.