What Is a Cancer Vaccine?


While we don’t have a vaccine that can directly prevent cancer, there are vaccines being used (and more being developed) that can both prevent certain causes of cancer and treat the disease itself. 

Currently, there are two types of cancer vaccines available: Preventive vaccines can protect you from oncoviruses, or viruses that are strongly linked to cancer, while therapeutic vaccines attack cancer cells. The United States currently has four preventive vaccines and three therapeutic vaccines that are approved by the Food and Drug Administration (FDA). 

Theresa Chiechi / Verywell


Preventive Vaccines

Preventive vaccines can prevent cancer caused by oncoviruses. The HPV vaccine is one example. It protects against human papillomavirus (HPV), a contagious virus that has been linked to cancers of the cervix, anus, throat, vagina, and penis. By preventing infection with the virus, the vaccine can prevent some cases of cancer. The vaccine must be given before the virus is present in the body, however. It will not protect against cancer that has already developed.

Preventive vaccines can only protect us from oncoviruses. There are other causes of cancer such as genetics and environmental exposures that aren’t affected by the vaccines. 

The following viruses have been linked to cancer:

  • HPV includes over 150 viruses that can lead to cancers of the cervix, vagina, anus, throat, head, and neck
  • Epstein-Barr virus (EBV) is a type of herpes virus, and is associated with nasopharyngeal cancer, certain types of lymphoma, and stomach cancer
  • Hepatitis B (HBV) and hepatitis C (HCV) viruses cause viral hepatitis, which can lead to liver cancer. HCV is also linked to non-Hodgkin lymphoma
  • Human immunodeficiency virus (HIV), the virus that causes AIDS, is not directly linked to cancer, but it has been shown to increase a person’s likelihood of being diagnosed with cancer. This may be due to the fact that the virus lowers the body’s ability to fight off oncoviruses. HIV has been linked to a higher risk of cervical cancer, Kaposi sarcoma, non-Hodgkin lymphoma, anal cancer, Hodgkin disease, lung cancer, skin cancer, liver cancer, and cancers of the mouth and throat
  • Human herpesvirus 8 (HHV-8), also known as Kaposi sarcoma–associated herpes virus (KSHV), is associated with Kaposi sarcoma
  • Human T-lymphotropic virus-1 (HTLV-1) has been linked to adult T-cell leukemia/lymphoma (ATL), a type of non-Hodgkin lymphoma and leukemia
  • Merkel cell polyomavirus (MCV) has been found in patients with Merkel cell carcinoma, a rare and aggressive form of skin cancer 

 There are currently four preventive vaccines:

  • Cervarix: Cervarix protects against the two strains of the HPV virus (types 16 and 18) that cause cervical cancer. HPV vaccines can help to prevent HPV-related cancers of the cervix, anus, throat, head and neck, vagina, and penis. Cervarix is no longer available in the United States due to production costs, but is still approved for use 
  • Gardasil: Gardasil protects against HPV types 16, 18, 6, and 11. Most healthcare provider offices now offer Gardasil-9 because it protects against more strains of HPV
  • Gardasil-9: Gardasil-9 protects against even more HPV types, including 16, 18, 31, 33, 45, 52, and 58. It also aids in the prevention of genital warts caused by HPV types 6 or 11. Gardasil-9 is given in three injections over the course of six months. It requires all three doses for maximum protection, and is recommended for both men and women 9 to 45 years old. Gardasil-9 is injected into the muscle of the upper arm or sometimes the thigh. Possible side effects are similar to those of other vaccines, and include pain and redness at the injection site, headache, and upset stomach 
  • Heplisav-B: The Hep-B vaccine protects against hepatitis B infection and hepatitis B-related liver cancer. This vaccine is usually given at birth, 1 month old, and 6 months old. The first dose is recommended within 24 hours of birth for all healthy newborns. It is injected into the muscle. Newborns receive this vaccine in the thigh, while older children would receive it in their upper arm 

HPV Vaccination Recommendations

The Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) developed recommendations for administering the HPV vaccine series. It’s recommended that the vaccine first be given to patients who are 11 or 12, but can be given as young as 9. If you were not given the vaccine as a child, ACIP recommends starting the vaccine through 26 years old. Adults aged 27 to 45 should talk with their healthcare provider about whether the vaccine is necessary for them. Many people in this age range have most likely already been exposed to HPV.

Patients under 15 years old should receive two vaccines; the second should be administered six to 12 months after the first. For patients starting the vaccine series in the 15 to 26 age range, they should receive a total of three doses over six to 12 months. A three-dose schedule is also appropriate for patients who are immunocompromised. 

Anyone who has ever had a life-threatening reaction, such as anaphylaxis, to a vaccine should not receive the HPV vaccine. People with hypersensitivity to yeast should also not receive a dose. If you currently have a moderate to severe illness, hold off on the vaccine until you are well. A minor illness like a mild cold will not affect the vaccine. HPV vaccines have not been studied in pregnant women, so it is best to delay the vaccine until after childbirth. Talk with your healthcare provider if you have questions about receiving the vaccine while you are breastfeeding. 

The most common side effect of the HPV vaccine is a reaction at the injection site. This usually involves redness or mild swelling and pain. 

Therapeutic Vaccines

Therapeutic vaccines work by stimulating the immune system to attack cancer cells. They have been proven effective at treating it. Each individual’s tumor is made up of unique cells and antigens. Because of this, therapeutic vaccines need to be individualized for each patient. 

Therapeutic vaccines are made up of cancer cells, parts of cancer cells, or proteins from the surface of cancer cells. This allows the body to recognize the disease and fight it. Sometimes a patient’s own immune cells are removed and exposed to these substances in the lab to create the vaccine. Once the vaccine is ready, it’s injected into the body to increase the immune response against cancer cells.

Because each vaccine is unique to the patient, the side effects can vary widely. According to the Cancer Research Institute, possible side effects of cancer vaccines include anorexia, nausea, back pain, fever and chills, fatigue, malaise, flu-like symptoms, headache, joint pain, muscle pain, and nerve pain. Therapeutic vaccines are currently only available for some types of cancer.

There are two types of therapeutic cancer vaccine:

  • Targeting tumor-specific antigens (TSAs): Some types of cancer produce cells that have too much of a certain protein or antigen on their surfaces. This type of vaccine can target those antigens on the surface of cancer cells
  • Oncolysis: These vaccines use oncolytic viruses to infect and kill cancer cells. The viruses can be either engineered or naturally occurring in cancer cells

Three FDA-approved therapeutic vaccines are currently available.

 Provenge (Sipuleucel-T)

The sipuleucel-T vaccine was approved in 2010 for the treatment of prostate cancer. When researchers discovered that prostate cancer cells overdevelop prostatic acid phosphatase (PAP) on their surface, they were able to target those cells with a vaccine. Your healthcare provider will collect your own immune dendritic cells using a process called leukapheresis. Those cells are then grown in a lab setting with the antigen PAP so that they are better able to recognize it in the body. Once the immune cells are administered, they are more effective at finding and destroying cancer cells. 

This treatment is usually given in three doses over one month. Each appointment takes about two hours, with the IV injection lasting for one hour. This vaccine is usually considered for patients with prostate cancer whose disease is not responding to hormone therapy. Studies show that this therapeutic vaccine reduced the risk of death by 22.5% in men with advanced prostate cancer. 

Possible side effects are usually mild, and can include:

  • Fever and chills
  • Fatigue
  • Headache
  • Back and joint pain
  • Nausea

Imlygic (Talimogene Laherparepvec)

This therapeutic vaccine is used to treat advanced melanoma, a form of skin cancer. It contains the substance cytokines, which are produced in the body and cause the immune system to activate. It is made from a genetically modified herpes virus. The vaccine is able to infect the cancer cells with the weakened virus, which slows and stops their growth. 

This medication is injected directly into your tumor by a specialist. The second dose is usually given about three weeks after the first; the specific dose depends on the size and nature of your tumor. Once you receive the treatment, the injection site should be covered with a clear dressing. This will prevent you from touching it and catching the virus. Your medical team and caregivers should also avoid touching the injection site. Possible side effects include flu-like symptoms, which are usually short-lived. Studies found that 16.3% of patients treated had a durable response; this means that their tumors either shrank or disappeared.

Bacillus Calmette-Guerin (BCG)

The BCG vaccine was originally developed to treat tuberculosis. It uses weakened bacteria to stimulate the immune system. It is now also used to treat early-stage bladder cancer. 

This treatment is administered directly into your bladder through a soft catheter by a healthcare provider. The drug stays in your bladder for two hours so that it can be absorbed by the cells lining your bladder. This medication attracts immune cells to your bladder, increasing your immune response to the cancer. This vaccine is used to keep bladder cancer from spreading or recurring.

The most common side effects are fever, chills, aches, and fatigue; they usually last for about two to three days after the treatment. If the BCG spreads to your bloodstream, it can cause a serious infection; this is rare but possible. The treatment schedule varies depending on the state of your disease. 

Immunotherapy Drugs and Treatments

Therapeutic vaccines are one of many immunotherapy treatment options. Immunotherapy treatments have been approved to treat several types of cancer but are not yet as common as chemotherapy, radiation and surgery. These drugs can be given in the form of a pill, intravenous (IV) medication, topical treatment, or intravesical delivery:

  • Monoclonal antibodies are immune system proteins that can be grown in a lab. Once administered, they can bind to cancer cells, making the cells more recognizable to the immune system
  • Checkpoint inhibitors block immune checkpoints. These checkpoints usually keep the immune system from responding too strongly to a virus. By eliminating the checkpoint, these drugs can help the immune system fight cancer more aggressively
  • T-cell transfer therapy involves removing the T-cells from the tumor, then treating them in the lab to better attack a specific type of cancer, then re-administering them through a needle in your vein
  • Immune system modulators are a general class of drugs that increase the immune system’s response to cancer 

Cancer Vaccines in Development

There are several new cancer vaccines on the horizon, and they use neoantigen personalized therapy. While some cancers overproduce normally occurring antigens on the surface of their cells, other types produce unique antigens known as neoantigens. These neoantigens are only seen on the cancer cells and never on healthy cells. Vaccines in the future will hopefully be able to identify these neoantigens and attack only cancer cells. This could theoretically eliminate side effects because the vaccine will not attack healthy cells.

Some of the personalized vaccine candidates that are entering or in phase III trials include: 

  • BiovaxID (dasiprotimut-T) is an immunotherapy treatment for non-Hodgkin’s lymphoma. Initial research has found that this vaccine extended disease-free survival time by 14 months 
  • Vitespen (oncophage) has been studied in kidney cancer and melanoma in phase III trials and is currently in phase II trials for gastric cancer, colorectal cancer, pancreatic cancer, non-Hodgkin’s lymphoma, and chronic myelogenous leukaemia. It is made from the proteins of cancer cells found directly in the tumor
  • There are also current studies or phase I trials underway for vaccines protecting against hepatitis C, Merkel cell polyomavirus, HHV-8 and HTLV-1 

A Word From Verywell

The development of cancer vaccines is an exciting discovery that we are just starting to understand. While not all types of cancer can be treated or prevented with vaccines currently, scientists are working to expand those preventive and treatment options. Talk with your healthcare provider about which vaccine, if any, may be a fit for you. If you or your family members have risk factors for cancers that are caused by oncoviruses, preventive vaccine may be suitable. Remember that preventive vaccines are usually given in childhood. Therapeutic vaccines may be helpful if your cancer is advanced or has not responded to treatment.



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