Federal health experts soon could approve COVID-19 booster shots for immunocompromised people

Most people who are sick with COVID-19 now have skipped vaccines. Others who are immunocompromised can get breakthrough cases and could benefit from an extra vaccine dose.
July 29, 2021
Booster shots for immunocompromised may help prevent breakthrough COVID-19 cases. An older cancer patient holds her granddaughter.
Booster shots for immunocompromised people like those with cancer and transplant patients could be approved soon. Photo: Getty Images.

Patients with compromised immune systems soon could be first in line in the U.S. to get COVID-19 booster shots and doctors on the front lines are eager to help vulnerable patients boost their antibodies.

An advisory committee for the Centers for Disease Control and Prevention (CDC) met on July 22 and reviewed evidence showing that fully-vaccinated, immunocompromised people are less protected from the coronavirus and could benefit from COVID-19 booster shots. Decisions from federal health authorities about COVID-19 booster shots could come soon.

Dr. Thomas Campbell supports booster shots for immunocompromised patients. He has had a unique vantage point during the pandemic. He has overseen clinical trials for COVID-19 vaccines at UCHealth University of Colorado Hospital on the Anschutz Medical Campus. Through his research, Campbell got an early look at how safe and remarkably effective the vaccines have been. He also has cared for patients who have been critically ill with the coronavirus.

As the highly transmissible delta variant overwhelms communities in Colorado, the U.S. and around the world, the number of hospitalized patients is spiking again.

More than 97% of patients currently hospitalized for COVID-19 across the U.S. have not received vaccines, according to CDC director, Dr. Rochelle Walensky.

But, doctors are seeing patients with breakthrough cases of COVID-19, meaning that the patients were fully vaccinated against COVID-19, yet still tested positive for the coronavirus. The people with breakthrough cases who have been the sickest have been those with compromised immune systems, Campbell and others have said.

For example, Campbell recently cared for a patient at University of Colorado Hospital who had received two doses of a COVID-19 vaccine months ago and still contracted COVID-19. The patient also has cancer and seemed more susceptible to a breakthrough case of COVID-19 due to underlying health problems. The patient did not need to be on a ventilator, but was very sick and needed supplemental oxygen, Campbell said.

“We want to try to prevent these breakthrough cases and there is good evidence now that an extra vaccine dose might help,” Campbell said.

Booster shots for immunocompromised patients could prevent breakthrough cases of COVID-19.Dr. Thomas Campbell, headshot.
Dr. Thomas Campbell supports booster shots for immunocompromised people to prevent breakthrough cases of COVID-19. Photo courtesy of Dr. Thomas Campbell.

In particular, people with cancer, rheumatoid arthritis, lupus and patients who have had organ or bone marrow transplants and those who are taking immunosuppressive medications have not been able to build up the same level of antibodies to COVID-19 as people without underlying health conditions.

“These immunocompromised people are at increased risk for getting very sick and being hospitalized for COVID-19,” Campbell said. “We know that giving them a third dose will increase the chance that they will have increased antibodies against the SARS-CoV2 spike proteins.”

Researchers are still learning whether increased antibodies in an immunocompromised patient’s body will help them ward off COVID-19.

But since COVID-19 vaccines are in good supply in the U.S. and some may expire soon, many patients and doctors are eager to see booster shots approved.

“The goal is to get protection,” Campbell said.

During the July meeting of the CDC’s Advisory Committee on Immunization Practices, Dr. Sara Oliver of the CDC presented research and data about immunocompromised people and COVID-19.

About 2.7% of adults are considered immunocompromised.

They include the following:

  • Cancer patients.
  • Organ and stem cell transplant patients.
  • People with immunodeficiencies.
  • People living with HIV.
  • Patients being treated with immunosuppressive medications such as chemotherapy, TNF blockers to stop inflammation tied to rheumatoid arthritis, certain biologic agents like rituximab and high-dose corticosteroids.

“Immunocompromised people are more likely to get more critically ill, have a longer illness and have lower antibody (levels) if they get SARS-CoV2 (the virus that causes COVID-19),” Oliver said.

“They also may be more likely to transfer the virus to healthy contacts,” she said.

Two studies, one in the U.S. and one in Israel, have shown that between 40 and 44% of breakthrough cases of COVID-19 among hospitalized patients have occurred in immunocompromised patients.

Research also is showing that immunocompromised people who are fully vaccinated against COVID-19 are not developing the same level of protection as healthier individuals, Oliver said. She cited one new study by several experts, including Dr. Adit Ginde, an Emergency Medicine doctor at UCHealth University of Colorado Hospital, that found that vaccines were highly effective in preventing hospitalizations for COVID-19. But, for immunocompromised patients, like transplant and cancer patients, the vaccines were effective about 60% of the time, lower than the 80 to 90% range for people with fully functioning immune systems.

The emerging research about booster COVID-19 shots for immunocompromised patients is showing potential benefits, Oliver said. Among patients who had no detectable antibody response to two doses of an mRNA vaccine, like Moderna or Pfizer, 30 to 50% of patients developed an antibody response to a third booster shot.

And, there were no serious adverse effects after the booster dose.

Other countries are beginning to recommend booster shots. France and Israel have recommended booster doses of COVID-19 vaccines for immunocompromised patients and medical experts in the United Kingdom are considering booster shots.

“The emerging data suggest that an additional dose may enhance the antibody response in some people,” Oliver said

CDC officials will continue to analyze vaccine responses and could soon decide whether to authorize booster doses of COVID-19 vaccines for immunocompromised patients.

About the author

Katie Kerwin McCrimmon is a proud Coloradan. She attended Colorado College thanks to a merit scholarship from the Boettcher Foundation and worked as a park ranger in Rocky Mountain National Park during summers in college.

Katie is a dedicated storyteller who loves getting to know UCHealth patients and providers and sharing their inspiring stories.

Katie spent years working as an award-winning journalist at the Rocky Mountain News and at an online health policy news site before joining UCHealth in 2017.

Katie and her husband, Cyrus — a Pulitzer Prize-winning photographer — have three adult children and love spending time in the Colorado mountains and traveling around the world.