Biological therapy for cancer is a type of treatment that uses the body's immune system to kill cancer cells.

Biological therapy for cancer can treat many types of cancer. It can prevent or slow tumor growth and prevent the spread of cancer. When cancer spreads, it's called metastatic cancer. Biological therapy for cancer often causes fewer toxic side effects than do other cancer treatments.

How biological therapy works

The goal of biological therapy for cancer is to get the immune system to see and kill cancer cells.

The body's immune system fights invaders, such as germs, throughout the body. Cancer cells are invaders, but the immune system doesn't always see them. Cancer cells can hide from immune system cells. Or cancer cells can keep immune system cells from acting.

In general, biological therapies work by:

  • Getting the immune system to attack cancer cells. There are several ways biological therapy treatments can do this. One way is putting chemicals that get the immune system working into the body. Another is training a sample of immune system cells from a person in a lab to attack cancer cells, then putting them back into that person's body.
  • Making cancer cells easier for the immune system to see. Biological therapy also can target the cancer cells, turning on or off cell signals that help them hide from the immune system. For example, drugs called immune checkpoint inhibitors can target certain receptors on the surface of the cancer cells. There they block the signals the cancer cells send to keep the immune system from seeing them.

Types of biological therapy

Several types of biological therapy exist, including:

  • Adoptive cell transfer
  • Angiogenesis inhibitors
  • Bacillus Calmette-Guerin therapy
  • Biochemotherapy
  • Cancer vaccines
  • Chimeric antigen receptor (CAR) T-cell therapy
  • Cytokine therapy
  • Gene therapy
  • Immune checkpoint modulators
  • Immunoconjugates
  • Monoclonal antibodies
  • Oncolytic virus therapy
  • Targeted drug therapy

Many types of biological therapy are available only in clinical trials. Biological therapy for cancer is a very active area of cancer research.

Products & Services

Get Mayo Clinic cancer expertise delivered to your inbox.

Subscribe for free and receive an in-depth guide to coping with cancer, plus helpful information on how to get a second opinion. You can unsubscribe at any time. Click here for an email preview.

I would like to learn more about

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

Clinical trials

Explore Mayo Clinic studies of tests and procedures to help prevent, detect, treat or manage conditions.

May 19, 2023
  1. Immunotherapy to treat cancer. National Cancer Institute. https://www.cancer.gov/about-cancer/treatment/types/immunotherapy. Accessed March 22, 2023.
  2. Papiez MA, et al. Biological therapies in the treatment of cancer — Update and new directions. International Journal of Molecular Sciences. 2021; doi:10.3390/ijms222111694.
  3. Niederhuber JE, et al., eds. Therapeutic antibodies and immunologic conjugates. In: Abeloff's Clinical Oncology. 6th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed March 22, 2023.
  4. Huang JL, et al. Targeting DNA damage response and immune checkpoint for anticancer therapy. International Journal of Molecular Sciences. 2022; doi:10.3390/ijms23063238.

Biological therapy for cancer