People with cancer are at an increased risk of severe illness due to COVID-19. This includes people with multiple myeloma, a type of blood cancer.

If you have multiple myeloma, getting a COVID-19 vaccination may seem intimidating. You may also be unsure how effective the vaccine will be if you’re undergoing certain types of treatments, such as chemotherapy. While multiple myeloma and its treatment can affect the vaccine’s efficacy, experts still recommend that you get a full dose as soon as possible.

Below, we’ll examine multiple myeloma, the COVID-19 vaccine, and how it works with multiple myeloma treatment. Keep reading to learn more.

Multiple myeloma (MM) is a blood cancer that affects plasma cells in the bone marrow. It’s rarer than other types of cancer and is estimated to make up only 1.8 percent of all new cancer diagnoses in the United States in 2022.

According to the Centers for Disease Control and Prevention (CDC), people with cancer are at an increased risk of severe illness due to COVID-19. This may also include people with a history of cancer.

A 2021 study comparing people with and without a history of cancer found that having received a cancer diagnosis was associated with poorer COVID-19 outcomes. This effect was strongest in people whose cancer was active.

Another 2021 study saw that compared to people without MM, those with MM were at a higher risk of developing COVID-19. The study also found that excess deaths in 2020, the year the pandemic began, were higher for people with MM.

Are people with multiple myeloma immunocompromised?

MM affects plasma cells, which typically go on to become immune cells called B cells. In MM, these cells become cancerous and begin to grow and divide out of control.

When this happens, healthy blood cells in the bone marrow, including other immune cells, are crowded out. As such, one of the effects of MM is a weakened immune system.

This means that if you have MM, you’re more vulnerable to infections. A 2015 study found that, compared to healthy people, individuals with MM had a 10-fold higher risk of contracting viral infections.

The side effects of some cancer treatments can also weaken the immune system. According to the American Cancer Society (ACS), chemotherapy (chemo) is the treatment that most often causes a weakened immune system.

How does multiple myeloma affect the COVID-19 vaccine?

Based on the above findings, it’s easy to see why people with MM might have a poorer response to vaccines, including the COVID-19 vaccine.

A 2022 study looked at neutralizing antibodies people with MM made after getting the COVID-19 vaccine. Though your body makes many types of antibodies after vaccination, the COVID-19 vaccine can actually block the virus from binding to a cell.

After analyzing samples from 238 people with MM, neutralizing antibodies were detected only in 54 percent of the samples. Those who received the Moderna vaccine had significantly higher levels than people who got the Pfizer-BioNTech vaccine.

This research indicates that people with MM do have a response to the vaccine, but the results decreased over time. While this is true of everyone (and why booster shots are required), the effects are more exacerbated in those with MM.

Researchers also reported that treatment-related factors played a role in the level of neutralizing antibodies that people made. Let’s look into this a little more now.

Because chemo weakens the immune system, the immune system may not respond as strongly to a vaccine. This means that the vaccine may be less effective at protecting you from an infectious disease.

You may also have heard that people receiving chemo shouldn’t receive some types of vaccines in the first place. Though this is true, it doesn’t apply to the COVID-19 vaccine.

Some older vaccines, such as the MMR and chickenpox vaccines, contain a weak form of a virus. Because the virus can still replicate in the body, this can cause potentially problems for someone with a weakened immune system.

The COVID-19 vaccines aren’t live vaccines. Because of this, they can safely be given to people with cancer who are getting immunosuppressive treatments like chemo and others.

There’s another important point to make on MM and chemo, though. According to the ACS, chemo is now a less important part of MM treatment because of newer, more effective treatments. But these newer treatments can also impact vaccine effectiveness as well.

Many of the treatment options for MM have side effects that affect how well the immune system works. But some may have a greater effect on COVID-19 vaccines. These treatments can include:

A 2021 study looked into the effectiveness of two doses of mRNA vaccines in people with MM. People actively receiving treatment for MM made lower levels of antibodies in response to two vaccine doses.

Researchers then broke down these results by treatment type. They found that some treatments were associated with significantly lower antibody responses. These include:

  • targeted therapy drugs that target a protein called CD38, including:
    • daratumumab and hyaluronidase (Darzalex Faspro)
    • isatuximab (Sarclisa)
  • treatments that target a protein called BCMA, such as:
    • belantamab mafodotin-blmf (Blenrep)
    • the CAR T-cell therapies ciltacabtagene autoleucel (Carvykti) and idecabtagene vicleucel (Abecma)

But a 2022 study found that getting a third dose of an mRNA vaccine increased antibody levels in people with MM, including in those receiving the treatments above.

COVID-19 vaccine side effects for those with cancer

Research has found that COVID-19 vaccine side effects in people with cancer are similar to those seen in the general population. These can include:

These side effects are typical and should go away within a few days. If they last longer or begin to worsen significantly, be sure to contact a doctor.

People with MM should receive the COVID-19 vaccine even though it may not be as effective as it is in individuals without MM. Getting vaccinated can prevent severe illness due to COVID-19.

The National Comprehensive Cancer Network recommends that all people with cancer get vaccinated for COVID-19 as soon as they can. But people receiving a stem cell transplant or CAR T-cell therapy should wait at least 3 months after treatment before getting vaccinated for the best effect.

The ACS supports this recommendation. The American Society of Hematology also recommends that people with MM get the COVID-19 vaccine, although the society notes that timing may depend on your overall health and treatment.

The CDC has a different recommended vaccine schedule for people with a weakened immune system, including those with MM. The table shows the vaccine schedule for immunocompromised adults at the time of publication.

VaccinePrimary series1st booster2nd booster
Pfizer-BioNTech (mRNA)Three doses. 2nd dose given 3 weeks after the first dose. 3rd dose given at least 4 weeks after the second dose.Given at least 3 months after the primary series.Must be mRNA, given at least 4 months after the 1st booster.
Moderna (mRNA)Three doses. 2nd dose given 4 weeks after the first dose. 3rd dose given at least 4 weeks after the second dose.Given at least 3 months after the primary series.Must be mRNA, given at least 4 months after the 1st booster.
Johnson & Johnson (adenoviral vector)Two doses. 2nd dose must be mRNA and is given at least 4 weeks after the first dose.Given at least 2 months after the primary series.Must be mRNA, given at least 4 months after the 1st booster.

The mRNA vaccines are preferred over the Johnson & Johnson (J&J) vaccine for the primary series and the boosters because mRNA vaccines are more effective and have a better safety profile than the J&J.

After your COVID-19 vaccination

People with MM are still at a high risk of COVID-19 even after being fully vaccinated. A 2021 study found that the risk of a breakthrough infection was 15.4 percent in people with MM, compared to 3.9 percent in those without cancer.

People with MM were also more likely hospitalized because of breakthrough infections. People with MM need to continue to take other preventive measures after vaccination, such as:

  • encouraging family, friends, and caregivers to get vaccinated
  • washing your hands frequently
  • wearing a well-fitting mask when you’re out in public
  • avoiding very crowded or poorly ventilated areas
  • staying at least 6 feet apart from others when in public
  • regularly disinfecting high-touch surfaces in your home, such as doorknobs and light switches

How to get vaccinated against COVID-19?

If you’re looking to get the COVID-19 vaccine, a good place to start is to ask a doctor or pharmacist if they’re providing COVID-19 vaccines.

If not, you can also find a vaccination site close to you using the Vaccines.gov search tool or contacting your state or local health department.

COVID-19 vaccines are free to all people in the United States. Vaccine providers will not ask you to pay any costs or fees when you get your vaccine.

People with MM are at an increased risk of developing COVID-19 and having a more severe illness. As such, people with MM should receive the COVID-19 vaccine.

Generally speaking, the COVID-19 vaccine is less effective in people with MM. This is due to the effects of cancer and certain treatments. Still, some protection from the vaccine is better than none.

If you have MM and haven’t yet been vaccinated, talk with your doctor about getting the COVID-19 vaccine. The exact timing of the vaccination may depend on your overall health and MM treatment plan.