Antibody-based therapies for multiple myeloma

Written by Lindsey Shapiro, PhD | Last updated Mar. 5, 2026
green checkbox Fact-checked by Joana Carvalho, PhD
Jump to:

Antibody-based therapies are a growing class of treatments used to manage multiple myeloma, a type of blood cancer in which immune plasma cells grow out of control in the bone marrow.

Broadly, these treatments bind to specific protein markers on myeloma cells, leading to their destruction. Over the years, scientists have developed multiple classes of antibody therapies that target myeloma in different ways.

Some of these treatments, particularly a group called CD38 inhibitors, can be used to treat newly diagnosed patients. However, most of them are used as a later line of treatment in people whose cancer has returned after (relapsed) or failed to respond to (refractory) initial treatment.

What are antibody-based therapies?

Antibodies are naturally occurring proteins that detect and bind to specific targets, or antigens, that the immune system deems harmful to the body. Their binding triggers an immune response to eliminate the threat.

Therapeutic antibodies, used to treat various cancers and other immune-mediated conditions, are lab-made antibodies that mimic this natural defense system.

In myeloma, antibody-based therapies are designed to bind to proteins on the surface of myeloma cells, either directly triggering immune-mediated cell death or delivering another cancer-killing medication.

Antibody-based therapies for multiple myeloma

There are a few different types of therapeutic antibodies that are used for myeloma:

  • monoclonal antibodies
  • bispecific antibodies
  • antibody-drug conjugates

While all of these medications bind to cancer cells and ultimately lead to their death, the specific mechanisms by which the malignant cells are killed differ between them.

Monoclonal antibodies

Monoclonal antibodies recognize and bind to proteins on the surface of myeloma cells, triggering their immune-mediated destruction through several mechanisms. They are considered a type of immunotherapy because they boost the immune system’s natural ability to kill cancer cells.

Monoclonal antibody therapies approved for myeloma include:

All are given by an infusion into the bloodstream (intravenously), except Darzalex Faspro, which is an under-the-skin (subcutaneous) injection formulation of Darzalex.

Empliciti targets the SLAMF7 protein on myeloma cells. It’s approved as part of various combination regimens for adults with relapsed or refractory disease.

Sarclisa, Darzalex, and Darzalex Faspro target the CD38 protein. Medications in this class are commonly used in treatment regimens for adults with both newly diagnosed and relapsed or refractory disease.

To date, Darzalex Faspro is the only medication that’s approved to treat people with an asymptomatic precursor condition called smoldering multiple myeloma who are at a high risk of progressing to active myeloma.

Bispecific antibodies

Bispecific antibodies are a newer class of myeloma immunotherapies. Instead of targeting a single protein, as monoclonal antibodies do, bispecific antibodies are designed to simultaneously bind to a target protein on myeloma cells and another on immune T-cells, which have natural cancer-killing abilities. By doing so, they act as a bridge, bringing T-cells into close proximity to the cancer cells they are meant to eliminate.

Bispecific antibodies approved for myeloma include:

Elrexfio, Tecvayli, and Lynozyfic target the BCMA protein on myeloma cells, while Talvey targets GPRC5D. All also bind to the CD3 protein on T-cells.

In the U.S., all of these treatments are used for heavily pretreated adults with relapsed or refractory multiple myeloma who have received three or four prior lines of treatment. Lynozyfic is given by intravenous infusion, while the others are given by subcutaneous injection.

Antibody-drug conjugates

Antibody-drug conjugates are a class of targeted treatments that combine an antibody with a cancer-killing chemotherapy drug. The antibody binds to a protein on the surface of myeloma cells, delivering the chemotherapy directly to the cancerous cells.

Blenrep (belantamab mafodotin-blmf) is the only such medication currently approved in the U.S. for myeloma. It uses a BCMA-targeted antibody to deliver the chemotherapy agent monomethyl auristatin F. Given by intravenous infusion, Blenrep is approved as part of a combination regimen for certain adults with relapsed or refractory multiple myeloma.

Side effects

The side effects of antibody-based treatments for myeloma will vary widely depending on the specific medication and dosing regimen, but could include:

  • infusion or injection-related reactions
  • low blood cell counts
  • infections
  • fatigue
  • gastrointestinal problems, such as nausea, diarrhea, constipation, or appetite loss

Certain classes of antibody therapies are associated with specific risks. For example, all bispecific antibodies carry boxed warnings for cytokine release syndrome, a type of systemic inflammatory response, or neurological toxicity.

Because this is a large group of treatments with many possible side effects, patients should talk with their doctors about what to expect with their specific regimen.

Rare Cancer News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.


Recommended reading