Immunotherapy for ovarian cancer

Immunotherapy helps to strengthen or restore the immune system's ability to fight cancer. This works to kill cancer cells and stop cancer cells from growing and spreading.

Researchers are continuing to look at how immunotherapy can be used to treat ovarian, fallopian tube and primary peritoneal cancers. You may have immunotherapy to treat advanced cancer that doesn't respond to other treatments or comes back (recurs) after treatment. If you have immunotherapy, your healthcare team will use what they know about the cancer and about your health to plan the drugs, doses and schedules.

Immune checkpoint inhibitors may be used for ovarian, fallopian tube and primary peritoneal cancer.

The immune system normally stops itself from attacking normal cells in the body by using specific proteins called checkpoints. Checkpoints slow down or stop an immune system response. Cells in the ovaries, fallopian tubes or peritoneum sometimes use these checkpoints to hide and avoid being attacked by the immune system. Immune checkpoint inhibitors work by blocking the checkpoint proteins so immune system cells (called T cells) attack and kill the cancer cells.

Immune checkpoint inhibitors may be offered if the cancer has certain genetic changes known as high microsatellite instability (MSI-H) or mismatch repair deficiency (dMMR).

If the cancer has either of these features, the following immune checkpoint inhibitors may be used:

• pembrolizumab (Keytruda)
• dostarlimab (Jemperli)

These immunotherapy drugs may not be covered by all provincial or territorial drug plans. Your doctor or healthcare team will discuss access to these drugs with you and about how you could benefit from this treatment.

Antibody-drug conjugates (ADCs) are monoclonal antibodies that are attached to a chemotherapy drug. They are sometimes called targeted therapy drugs because they target certain proteins on the surface of cancer cells.

Mirvetuximab soravtansine (Elahere) is an ADC used to treat ovarian, fallopian and primary periotoneal cancer that has large amounts of a protein called folate receptor alpha (FRa) in the cancer cells. It may be used for cancers that have stopped longer responding to platinum chemotherapy drugs and have already been treated with 1-3 other drug therapies.

Side effects of immunotherapy will depend mainly on the type of drug or drug combination, the dose, how it's given and your overall health. Tell your healthcare team if you have side effects that you think might be from immunotherapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Common side effects of immunotherapy for ovarian, fallopian tube or primary peritoneal cancer include:

• flu-like symptoms, such as fever and chills

• fatigue

• skin problems, including redness, rash, itching and dryness

• diarrhea

• constipation

• nausea and vomiting

• eye and vision problems

All drugs, including those used to treat cancer, are approved for use in Canada by Health Canada. If a drug is mentioned on cancer.ca, it means that Health Canada has approved the drug and pharmaceutical companies sell it in Canada. It does not mean that the drug is offered everywhere in Canada.

Paying for drugs is the responsibility of provincial and territorial health departments. Each health department makes its own decisions about which drugs to cover (pay for) in that province or territory. This means that a drug may be covered in one province, but not in others.

Your oncologist will talk to you about different drug treatments and what is available through your provincial or territorial drug program.

Find out more about immunotherapy. To make the decisions that are right for you, ask your healthcare team questions about immunotherapy.

Details on specific drugs change regularly. Find out more about sources of drug information and where to get details on specific drugs.