People Diagnosed With Cancer Benefit From Moderna COVID-19 Vaccine
People diagnosed with cancer developed antibodies to the COVID-19 virus after receiving the Moderna vaccine. Still, they had lower antibody levels than people who hadn’t been diagnosed with cancer, according to a study.
The research was published online on March 10, 2022, by the journal JAMA Oncology. Read “Evaluation of Antibody Response to SARS-CoV-2 mRNA-1273 Vaccination in Patients With Cancer in Florida.”
About the Moderna COVID-19 vaccine
The Moderna vaccine works by using genetic material called messenger RNA (mRNA). The mRNA vaccines contain a small piece of the coronavirus’s mRNA, which tells your body to make copies of a protein in the virus called the spike protein. Your immune system then builds up immune cells and special proteins (antibodies) to fight the spike protein. So, if you’re ever exposed to the COVID-19 virus, your immune system is ready to recognize the virus and protect you from infection. Because the vaccine contains just a small piece of the virus, it cannot cause COVID-19 and is considered safe for immunocompromised people. Still, earlier studies suggest that the Moderna vaccine — as well as the other two vaccines, Pfizer-BioNTech and Johnson and Johnson (J&J) — may offer less protection against COVID-19 in people with weakened immune systems.
The Moderna vaccine is marketed under the brand name Spikevax and has full approval from the Food and Drug Administration (FDA) for people ages 18 and older. The Moderna vaccine consists of two injections, which are given four weeks apart in the upper arm muscle.
The FDA has authorized a Moderna vaccine booster shot for all adults ages 18 and older five months after their second shot. A second Moderna booster shot is authorized for:
adults ages 50 and older
young children between the ages of 12 and 17 who have had solid organ transplants or are immunocompromised
COVID-19 vaccines and people with weakened immune systems
It’s important to know that COVID-19 vaccine recommendations are different for people with weakened immune systems (called immunocompromised). Several breast cancer treatments — including chemotherapy, certain targeted therapies, and immunotherapy — can weaken your immune system. People with moderately to severely compromised immune systems are especially vulnerable to COVID-19, and may not build the same level of immunity to the virus after being fully vaccinated as people who are not immunocompromised.
If you’re currently being treated for breast cancer, it’s a good idea to ask your doctor if you should follow these recommendations from the Centers for Disease Control and Prevention (CDC) for moderately to severely immunocompromised people:
If your initial vaccine was Pfizer or Moderna, the CDC recommends you get a third dose of the same vaccine you received initially at least 28 days after your second dose.
After the third dose of either the Pfizer or Moderna vaccine, you should receive a booster dose of any of the three vaccines at least three months after your third dose.
If your initial vaccine was J&J, the CDC recommends you get a second dose of either the Pfizer or Moderna vaccine at least 28 days after receiving the vaccine. The CDC also recommends a booster dose of either the Pfizer or Moderna vaccine at least two months after your second dose. An mRNA vaccine booster is preferable for people ages 18 and older. But people may consider the J&J vaccine if they’ve had a severe allergy to an mRNA vaccine, if there is a shortage of mRNA vaccines, or if they strongly prefer the J&J vaccine.
In addition, the FDA has granted emergency use authorization to Evusheld (chemical name: tixagevimab combined with cilgavimab), an antibody therapy used to prevent COVID-19 in people ages 12 and older who have moderately to severely compromised immune systems or cannot get a COVID-19 vaccine because of a severe allergic reaction to its ingredients. Evusheld works differently from a vaccine, and may be an option for immunocompromised people who may not develop enough immunity after a COVID-19 vaccine.
About the study
A 2021 CDC study found that the Moderna and Pfizer COVID-19 vaccines help keep people with weakened immune systems out of the hospital if they’re infected with the COVID-19 virus. Still, people with weakened immune systems, including people diagnosed with cancer, didn’t develop as many antibodies to the virus as people with fully functioning immune systems.
In this study, the researchers wanted to know if the response to the Moderna vaccine was different in people diagnosed with solid tumor cancers — like breast cancer — than in people diagnosed with hematologic cancers. Hematologic cancers begin in blood-forming tissues or in immune system cells, and include leukemia, lymphoma, and multiple myeloma.
The study included 515 people with an average age of 64.5 years who were receiving cancer treatment at the Moffitt Cancer Center in Tampa, Florida. All the people received the Moderna vaccine between Jan. 12 and Jan. 25, 2021.
The researchers took blood samples from the people in the study the day before the first and second dose of the vaccine and about 1.5 months after the second dose.
The researchers also took blood samples from 18 people who had never been diagnosed with cancer 14 to 60 days after their second Moderna vaccine dose.
Of the people in the study:
50.9% were women
49.1% were men
93% were white
6.2% were Hispanic
58.4% were diagnosed with hematologic cancer
41.6% were diagnosed with solid tumor cancer
3.3% had COVID antibodies before receiving the Moderna vaccine, meaning they likely had been infected with COVID-19 before receiving the vaccine
71.3% of the people in the study developed COVID antibodies after the first dose of the Moderna vaccine
90.3% of the people in the study developed COVID antibodies after the second dose of the Moderna vaccine
When people develop COVID antibodies after receiving one of the vaccines, doctors call it seroconversion.
After the second dose of the vaccine, people diagnosed with hematologic cancers were less likely to develop COVID antibodies than people diagnosed with solid tumor cancers:
84.7% of the people diagnosed with hematologic cancers developed COVID antibodies after the second vaccine dose
98.1% of the people diagnosed with solid tumor cancers developed COVID antibodies after the second vaccine dose
The researchers also found differences in COVID antibody development after vaccination among people diagnosed with different types of hematologic cancers:
65.2% of the people diagnosed with chronic lymphocytic leukemia developed COVID antibodies
58.2% of the people diagnosed with B-cell non-Hodgkin lymphoma developed COVID antibodies
People who received treatment for either chronic lymphocytic leukemia or B-cell non-Hodgkin lymphoma were the least likely to develop COVID antibodies after vaccination. People who received anti-CD20 monoclonal antibody treatment in the six months before getting the Moderna vaccine were less likely to develop antibodies than people who received this treatment six to 24 months before getting the Moderna vaccine.
The researchers also looked at how other treatments for hematologic cancers affected COVID antibody development:
33.3% of the people treated with Bruton tyrosine kinase (BTK) inhibitors developed COVID antibodies
none of the people treated with PI3K inhibitors developed COVID antibodies
50% of the people treated with Venclexta (chemical name: venetoclax) developed COVID antibodies
The people in the study diagnosed with cancer had lower COVID antibody levels after receiving the Moderna vaccine than people who had not been diagnosed with cancer. Still, people diagnosed with cancer who had COVID antibodies before receiving the vaccine had higher levels than people diagnosed with cancer who didn’t have COVID antibodies before receiving the vaccine. Antibody levels were:
7,303.7 arbitrary units (AU)/milliliter of blood (mL) in people who had not been diagnosed with cancer
6,821.0 AU/mL in people diagnosed with cancer who had COVID antibodies before being vaccinated
1,754.6 AU/mL in people diagnosed with solid tumor cancers
745.6 AU/mL in people diagnosed with hematologic cancers
“Although we did see higher seroconversion rates among solid tumor patients, it is important to point out the antibody titers were lower than seen in healthy adults,” Anna Giuliano, PhD, founding director of the Center for Immunization and Infection Research in Cancer at Moffitt and lead author of the study, said in a statement. “Unfortunately, we don’t know how much antibody a person needs to provide full protection against the virus.”
What this means for you
If you’ve been diagnosed with breast cancer, these results can help answer questions you might have about how well the Moderna vaccine may work for you.
It’s true that people diagnosed with breast cancer don’t seem to develop as many COVID antibodies as people who haven’t been diagnosed with cancer. But they do develop more antibodies than people who have been diagnosed with blood or immune system cancers.
Like other studies, this study strongly suggests that people diagnosed with breast cancer benefit from getting a COVID-19 vaccine.
Still, everyone’s situation is different, and it makes sense to talk with your doctor about getting vaccinated and when to get a booster.
Learn more about COVID-19 Vaccine Facts for People With Breast Cancer.
Editor’s Note: This article was updated on June 9, 2022, with additional information on second Moderna booster shots and Evusheld.
Written by: Jamie DePolo, senior editor
— Last updated on July 14, 2022, 4:37 PM