How Effective Is Immunotherapy in the Treatment of Non-Small Cell Lung Cancer & What are its Side Effects?

When you get diagnosed with cancer in the lungs, it is known as lung cancer. There are two major types of lung cancer – non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Non-small cell lung cancer is the most common type of lung cancer, known to make up almost 80 to 85 percent of all lung cancer diagnoses. This type of cancer does not spread as rapidly as small cell lung cancer.^{(1, 2, 3, 4)}

There are three main types of Non-Small Cell Lung Cancer (NSCLC), including:

• Large cell carcinoma
• Squamous cell carcinomas
• Adenocarcinomas

Once you have been diagnosed with non-small cell lung cancer (NSCLC), your doctor will discuss the various treatment options with you. If you are diagnosed with early-stage cancer, the first choice of treatment is usually surgery. In advanced stages of cancer, your doctor will recommend a treatment plan that combines surgery, radiation, chemotherapy, or a combination of all three. In many cases, immunotherapy is recommended as a second line of treatment for non-small cell lung cancer (NSCLC). This means that you become a candidate for immunotherapy if the first line of treatment, or drug, does not work or stops working for you. Of course, there are some cases where doctors use immunotherapy as the first line of treatment as well in combination with other medications, especially in late-stage cancers that have spread throughout the body.^{(5, 6)} Read on to find out everything about immunotherapy for non-small cell lung cancer (NSCLC).

Immunotherapy helps fight against non-small cell lung cancer (NSCLC) by stimulating the immune system to search and kill the cancer cells. The drugs that are used in immunotherapy that are used in the treatment of non-small cell lung cancer (NSCLC) are known as checkpoint inhibitors.

The immune system has its own army of cells that find and kill cancer cells and any other dangerous foreign invader cells and destroy them. These cells are known as T cells. Checkpoints in the immune system are basically proteins present on the surface of cells that let the T cells know whether a particular cell is harmful or friendly. Checkpoints help protect the healthy cells of the body by preventing the immune system from destroying them.^{(7, 8, 9)}

Cancer cells sometimes also make use of these checkpoints to remain hidden from the immune system. Checkpoint inhibitors help block the checkpoint proteins in order to allow T cells to recognize the cancer cells and eventually destroy them. These drugs work by taking off the ‘brakes’ on your immune system’s fight against the invading cancer cells.⁽¹⁰⁾

There are four major immunotherapy drugs or checkpoint inhibitors that are used in the treatment of non-small cell lung cancer (NSCLC). These include:

• Atezolizumab (brand name: Tecentriq) and durvalumab (brand name: Imfinzi): These checkpoint inhibitors work by blocking a protein known as PD-L1 that is located on the surface of immune cells and tumor cells. The blocking of the protein PD-L1 helps unleash the body’s immune response against the cancer.^{(11, 12)}
• Ipilimumab (brand name: Yervoy): Ipilimumab helps block another protein known as CTLA-4, which is located on the surface of T Cells. Blocking this protein along with the blocking of another protein, PD-1 protein, or in combination with chemotherapy, also helps unleash the immune response of the body to fight against the cancer.^{(13, 14)}
• Cemiplimab (brand name: Libtayo), Pembrolizumab (brand name: Keytruda), and Nivolumab (brand name: Opdivo): These drugs work by blocking the protein known as PD-1 that is present on the surface of T cells. The protein PD-1 stops the T cells from attacking the cancer cell, and blocking PD-1 help the immune system find and destroy the cancer cells.⁽¹⁵⁾

Not everyone with non-small cell lung cancer (NSCLC) is eligible for getting immunotherapy. Doctors make use of Tecentriq, Keytruda, and Opdivo as the second-line therapy for treating non-small cell lung cancer (NSCLC). You may be eligible to get one of these immunotherapy drugs if your cancer has begun to grow and spread once again after undergoing chemotherapy or another cancer treatment. The drug Keytruda is sometimes also administered as a first-line treatment in cases of advanced stage non-small cell lung cancer (NSCLC), in combination with chemotherapy.^{(16, 17)}

On the other hand, the drug Imfinzi is used to treat those with stage 3 non-small cell lung cancer (NSCLC) and who are not eligible for surgery, but at the same time, their cancer has not gotten worse after undergoing radiation and chemotherapy. Imfinzi helps prevent the cancer from growing without restrictions.

The various immunotherapy drugs are administered as an infusion through a vein in the arm. You have to receive these immunotherapy drugs at least once every two to three weeks.

Many people with non-small cell lung cancer (NSCLC) have experienced significant improvement after using immunotherapy drugs. The treatment was successful in reducing their tumors and also stopped the cancer from spreading for several months. However, not everyone responds to treatment with immunotherapy. They may find that the cancer stops growing for a while and then comes back. Researchers are still trying to understand which types of cancer respond best to immunotherapy. This will help doctors target immunotherapy to treat those people who will be able to get the most benefit from it.^{(18, 19)}

Just like any form of treatment, there are some side effects associated with immunotherapy as well. Some of the common side effects of immunotherapy drugs include:

• Nausea
• Cough
• Fatigue
• Itching
• Loss of appetite
• Rash
• Joint pain
• Constipation
• Diarrhea

Severe side effects from immunotherapy are usually rare because these drugs help increase the response of the immune system, and the immune system can begin an attack on other organs such as the liver, kidneys, or lungs. This could prove to be serious if not attended to at the earliest.^{(20, 21, 22)}

In most cases of non-small cell lung cancer (NSCLC), the cancer is not diagnosed until it has already reached an advanced stage, which makes it challenging to treat it with surgery, radiation, or chemotherapy. Immunotherapy has helped improve the treatment of non-small cell lung cancer (NSCLC).

In immunotherapy, checkpoint inhibitor drugs are used to help slow down the growth of the cancer that has spread through the body. However, these drugs don’t work for everyone, but they can dramatically help some people with advanced-stage non-small cell lung cancer (NSCLC). The cancer can go into remission and also help a person live longer.

Research is ongoing to study new immunotherapy drugs through clinical trials. It is expected that new drugs or new combinations of these drugs, along with radiation or chemotherapy, can help improve the survival rate of non-small cell lung cancer (NSCLC). If you want to find out if immunotherapy drugs can help you, you should speak to your doctor or oncologist.

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