Immunotherapy is a treatment that strengthens the immune system, helping the body better fight infections, cancer, and autoimmune diseases.
It is usually recommended when other treatments have not produced satisfactory results, and its use must always be evaluated and supervised by a doctor.
In cancer treatment, immunotherapy can be used when other therapies, such as chemotherapy or radiation therapy, are not effective or cause severe side effects. It may be given alone or in combination with other treatments to stimulate the immune system to attack tumor cells.
Indications for use
Immunotherapy may be recommended in the following situations:
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Cancer, when other treatments are not effective or cause severe side effects;
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Autoimmune diseases, such as rheumatoid arthritis, multiple sclerosis, and Crohn’s disease;
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Allergies, to reduce sensitivity to allergens like pollen, dust, or insect stings;
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Severe infections, when the immune system needs support to fight hard-to-treat viruses or bacteria;
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Organ transplants, to prevent rejection of the transplanted organ by controlling the immune response through immunosuppressive therapy.
Immunotherapy may also be used when other treatments cause strong side effects or when the disease responds better to immune-based therapy.
Main types
The main types of immunotherapy include:
1. T-cell transfer therapy (CAR T-cell therapy)
T-cell transfer therapy, also known as adoptive cell therapy, involves collecting immune cells that attack tumors or inflammation, analyzing them in a lab, and selecting the most effective ones to help fight the disease.
After analysis, the person’s immune cells are modified or multiplied in the lab (such as in CAR T-cell therapies)and then reintroduced into the body in large numbers to make it easier to fight the disease.
This type of therapy is mainly used for cancers such as leukemia, lymphoma, and advanced melanoma.
2. Checkpoint inhibitors
Immune checkpoint inhibitors are medications that block the immune system’s natural control points, allowing defense cells to respond more strongly against diseases.
This treatment is most often used for cancers of the skin, lungs, bladder, kidneys, and head and neck.
3. Monoclonal antibodies
Monoclonal antibodies are lab-made proteins that attach to cancer cells or immune system targets, helping mark the cancer for destruction or boost the activity of immune cells.
Some monoclonal antibodies can carry substances such as chemotherapy drugs or radioactive molecules, which help prevent tumor growth.
In addition to cancer, monoclonal antibodies are also used for autoimmune diseases like rheumatoid arthritis, multiple sclerosis, and Crohn’s disease.
4. Cancer vaccines and oncolytic virus therapy
Therapeutic cancer vaccines train the immune system to recognize tumor antigens. In the US, options include the FDA-approved sipuleucel-T, used for certain prostate cancers.
Oncolytic virus therapy, such as talimogene laherparepvec (T-VEC), is another form of immunotherapy that uses modified viruses to target and destroy cancer cells and is approved for unresectable recurrent melanoma.
These approaches help the immune system detect and eliminate cancer cells and may also reduce the risk of recurrence after other treatments.
5. Immune system modulators
Immune system modulators, including cytokine therapies such as interleukins and interferons, strengthen the overall or targeted immune response. They are used for conditions like cancer, autoimmune disorders, inflammatory bowel disease, allergies, asthma, and infections.
Treatment administration
Immunotherapy can be administered in several forms, depending on the condition and type of treatment:
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Intravenous (IV), which is the most common method;
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Oral, as pills or capsules;
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Topical, as a cream for certain early-stage skin cancers;
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Intravesical, administered directly into the bladder (for example, BCG therapy for early-stage bladder cancer);
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Subcutaneous injections, including subcutaneous or sublingual allergy immunotherapy.
The frequency and duration of treatment depend on the condition, the type of immunotherapy, and individual response. It may be given daily, weekly, or in cycles, with breaks to allow the body to recover and produce new healthy cells.
During treatment, the person is monitored with medical tests to evaluate how the disease is responding and to check for possible side effects.
Immunotherapy stimulates the immune system but does not provide quick symptom relief. Therefore, doctors may combine it with other medications, such as anti-inflammatories, corticosteroids, or pain relievers, to ease discomfort.
The effectiveness of immunotherapy can also be influenced by gut health, as a balanced microbiota may improve immune response. Maintaining a fiber-rich diet or, in some cases, undergoing a fecal microbiota transplantation can help support treatment results.
Immunotherapy for cancer
Immunotherapy helps the immune system fight cancer by stimulating or regulating the body’s defense mechanisms to target tumor cells.
It can be used when other treatments, such as chemotherapy or radiation therapy, are not sufficient or cause significant side effects.
Different types of immunotherapy for cancer include medications that enhance immune cell activity, antibodies that tag cancer cells, vaccines that train the body to recognize tumors, and cell-based therapies.
Close medical follow-up is essential to monitor side effects and evaluate how well the treatment is working.
Side effects
The most common side effects of immunotherapy include:
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Fatigue;
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Fever and chills;
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Nausea and loss of appetite;
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Headache or dizziness;
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Muscle discomfort.
When immunotherapy is given by injection or infusion, local reactions may occur at the application site, such as pain, redness, or swelling.
More serious but rare side effects can include inflammation of organs like the lungs, liver, intestines, or heart due to excessive immune activation, as well as severe allergic reactions such as anaphylaxis.