Immunotherapy for Cancer: How It Works, Types, Cost and Side Effects

What Is Immunotherapy?

Immunotherapy is a form of cancer treatment that uses medicines to help the immune system find and destroy cancer cells. It does not directly poison or burn cancer cells like chemotherapy or radiation. Instead, it removes the “brakes” that stop the immune system from attacking cancer, or it gives the immune system new tools to identify tumour cells.

How the Immune System Fights Cancer

The immune system is made up of white blood cells, antibodies, and organs such as the spleen and lymph nodes. It constantly checks the body for infections and abnormal cells. When it detects unusual cells, it destroys them before they multiply.

Cancer cells are able to hide from this defence in several ways. They can disguise themselves as healthy cells or press “checkpoint” proteins on immune cells, which act like brakes and stop the immune system from attacking. Immunotherapy medicines are designed to release these brakes or restore the immune system’s ability to see the cancer clearly.

Main Types of Cancer Immunotherapy

• Immune Checkpoint Inhibitors (ICIs) These are the most widely used immunotherapy drugs today. They block checkpoint proteins such as PD-1, PD-L1, or CTLA-4 that cancer cells exploit to switch off the immune response. Once the checkpoints are blocked, T-cells can attack the tumour.
• Adoptive Cell Therapy (ACT), including CAR T-cell therapy In this personalized approach, the patient’s own T-cells are collected, modified in a laboratory to recognise cancer cells, multiplied, and infused back. CAR T-cell therapy has shown strong results in certain blood cancers such as some types of leukaemia and lymphoma.
• Monoclonal Antibodies Laboratory-made antibodies that either flag cancer cells for immune attack, block growth signals, or carry chemotherapy directly to the tumour cell (antibody-drug conjugates).
• Cancer Treatment Vaccines Unlike vaccines that prevent infection, treatment vaccines train the immune system to recognise cancer-specific markers. Sipuleucel-T, used in some cases of prostate cancer, is one example.
• Cytokines and BCG Therapy Cytokines such as interleukins and interferons boost immune activity in general. BCG (Bacillus Calmette-Guérin), a weakened tuberculosis bacterium, is instilled into the bladder to treat early-stage bladder cancer by triggering a local immune response.

Common Immunotherapy Drugs in India

Several immunotherapy drugs are now approved and available in India. The choice depends on the cancer type, stage, and biomarker testing.

• Pembrolizumab (Keytruda): A PD-1 inhibitor used in lung cancer, melanoma, head and neck cancers, some bladder and kidney cancers, and select breast and cervical cancers.
• Nivolumab (Opdivo): A PD-1 inhibitor used in lung cancer, kidney cancer, melanoma, Hodgkin lymphoma, and head and neck cancers.
• Atezolizumab (Tecentriq): A PD-L1 inhibitor used in lung, bladder, and some breast cancers.
• Ipilimumab (Yervoy): A CTLA-4 inhibitor, often combined with nivolumab in advanced melanoma and kidney cancer.
• Durvalumab (Imfinzi): A PD-L1 inhibitor used in stage III lung cancer and bladder cancer.
• Rituximab: A monoclonal antibody used in non-Hodgkin lymphoma and some autoimmune conditions.
• Trastuzumab (Herceptin): Used in HER2-positive breast cancer.

Your medical oncologist will decide which drug is appropriate based on the cancer type, biomarker test results, and prior treatments.

Cancers Where Immunotherapy Is Used

Immunotherapy is not equally effective for every cancer. It has shown the strongest results in:

• Melanoma and other skin cancers
• Non-small cell lung cancer
• Kidney (renal cell) cancer
• Bladder cancer
• Head and neck cancers
• Hodgkin lymphoma and certain non-Hodgkin lymphomas
• Some cases of breast cancer, cervical cancer, and colorectal cancer with specific biomarkers
• Selected leukaemias (CAR T-cell therapy)

Immunotherapy vs Chemotherapy

Both are cancer treatments, but they work differently and have distinct side-effect profiles.

Many patients today receive chemotherapy and immunotherapy together, because the combination can be more effective than either alone.

Side Effects and How They Are Managed

Immunotherapy is generally better tolerated than chemotherapy, but it can cause immune-related adverse events (irAEs) when the activated immune system attacks healthy tissue. Common side effects include:

• Fatigue and mild fever
• Skin rash and itching
• Diarrhoea or colitis
• Thyroid dysfunction (under- or over-active thyroid)
• Pneumonitis (inflammation of the lungs)
• Hepatitis (liver inflammation)
• Endocrine problems affecting the adrenal or pituitary glands
• Joint pain

Most side effects respond well to steroids and dose adjustments if reported early. Your oncologist will monitor thyroid, liver, and kidney function with blood tests before each cycle. Never delay reporting new symptoms; early intervention is what makes immunotherapy safe.

Immunotherapy Cost in India

Immunotherapy cost in India varies widely depending on:

• The specific drug prescribed
• Dose (calculated by body weight or fixed)
• Number of cycles required, which depends on cancer type and stage
• Whether it is given alone or combined with chemotherapy
• Whether the drug is branded or a biosimilar, where available

A single infusion cycle can range from roughly ₹75,000 to ₹4,00,000 or more per session, with treatment typically continuing for several months to two years. Biosimilar versions of some immunotherapy drugs are now available in India at lower cost than the original branded product.

Some patients may qualify for financial assistance under:

• Mahatma Jyotirao Phule Jan Arogya Yojana (MJPJAY) — Maharashtra state scheme
• Ayushman Bharat (PM-JAY) — national scheme
• CGHS — for central government employees
• Pharmaceutical company patient-access programmes
• Health insurance policies that specifically cover targeted therapy and immunotherapy

Onco-Life is empanelled under MJPJAY, PM-JAY, and CGHS. Eligibility criteria apply; please check government scheme eligibility before your visit and discuss cost planning with your treating team.

The Immunotherapy Treatment Process

Step 1: Diagnosis and biomarker testing Your oncologist will confirm the cancer type, stage, and check biomarkers such as PD-L1 expression, tumour mutational burden (TMB), or microsatellite instability (MSI). These tests predict whether immunotherapy is likely to help.

Step 2: Treatment planning The team decides whether immunotherapy is used alone, or combined with chemotherapy, targeted therapy, or radiation. This is often discussed at the Virtual Tumour Board.

Step 3: Infusion Most immunotherapy drugs are given intravenously as daycare treatment. Sessions usually last 30 to 60 minutes and are repeated every two to six weeks.

Step 4: Monitoring Blood tests, thyroid function, and periodic imaging track how the tumour is responding and detect any immune-related side effects early.

Step 5: Follow-up Treatment continues for months to two years, depending on the cancer type and response. Long-term follow-up remains important, as some side effects can appear even after treatment ends.

Immunotherapy in Combination with Other Treatments

Immunotherapy often works better in combination:

• Chemotherapy plus immunotherapy is now standard in many advanced lung cancers.
• Radiation therapy can expose hidden tumour markers, helping the immune system recognise cancer more clearly.
• Surgical removal of the main tumour combined with immunotherapy can reduce recurrence in select cases.

 Immunotherapy Care at Onco-Life

At Onco-Life Cancer Centre, immunotherapy is planned and delivered by experienced medical oncologists, supported by trained infusion nurses, dietitians, and palliative care specialists. Every patient benefits from:

• Biomarker testing coordinated in-house or through partner laboratories
• Multidisciplinary review through the Virtual Tumour Board
• Daycare infusion, so patients return home the same day
• Structured monitoring for immune-related side effects
• Integrated palliative care and nutrition support

Onco-Life offers immunotherapy at its cancer centres in Pune, Chiplun, Satara, and Talegaon Dabhade, and consults with patients travelling from Mumbai, Kolhapur, Solapur, and other parts of Maharashtra.

To discuss whether immunotherapy is right for your cancer type, Book a Doctor Appointment or request a Second Opinion.

Disclaimer

This content is for informational purposes only and does not constitute medical advice. The signs, diagnosis, and treatment of brain tumours vary from person to person. Please consult a qualified doctor or oncologist for diagnosis and treatment decisions.

References

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