Immunotherapy and targeted therapies

What is immunotherapy and how does it work?

Immunotherapy is a treatment that helps your own immune system recognise and respond to the illness. It works differently from standard treatments like chemotherapy and radiation, which attack the illness directly. The immune system is powerful but can be blocked or suppressed by certain conditions. Immunotherapy drugs remove those blocks or activate the immune response in targeted ways.

There are several types of immunotherapy. Checkpoint inhibitors are the most commonly used in Australia. They work by releasing a brake on the immune system that certain illnesses use to hide. Other forms include monoclonal antibodies, which are laboratory-made proteins that target specific markers on cells, and adoptive cell therapies, which involve engineering a patient's own immune cells.

Immunotherapy can have significant side effects. Because it activates the immune system broadly, it can cause inflammation in organs that have nothing to do with the original illness. These side effects are manageable if caught early, which is why regular monitoring is important during treatment.

What are targeted therapies?

Targeted therapies are drugs designed to interfere with specific molecules that certain illnesses need to grow and spread. Rather than attacking all fast-dividing cells, they focus on a particular biological weakness. This means they can be more effective for the right person and may cause fewer side effects than traditional chemotherapy.

Whether a targeted therapy is relevant depends entirely on the biology of your condition. A biomarker test, sometimes called molecular or genomic profiling, identifies whether your condition has the specific characteristics that a targeted therapy is designed to address. Without that testing, it is not possible to know whether a targeted therapy could help.

Not everyone will have a targetable mutation or marker. But the only way to know is to test. See the genomic profiling guide for more on how this testing works and how to ask for it.

Who are these treatments suitable for?

Eligibility depends on the specific condition, its biology, which biomarkers are present, and what prior treatments have been received. It is not possible to generalise. Two people with the same diagnosis may have completely different eligibility for the same drug.

What you can do is ask whether biomarker testing has been done or is appropriate, and what treatment options that testing might open up. Your specialist will be able to tell you whether immunotherapy or targeted therapy is relevant in your case, and why or why not.

Some treatments are only available to people who have not received certain prior therapies. This is why asking early matters. Waiting to ask until standard treatment has stopped working can mean some options are no longer available.

Is immunotherapy or targeted therapy covered by the PBS?

The Pharmaceutical Benefits Scheme (PBS) subsidises many medications in Australia, making them affordable. Services Australia (servicesaustralia.gov.au) has information on the PBS, current co-payment amounts, and the SafetyNet threshold for concession card holders. Some immunotherapy and targeted therapy drugs are PBS-listed, meaning the cost is subsidised and a standard prescription co-payment applies. Others are not PBS-listed and can cost tens of thousands of dollars per treatment cycle.

PBS listing depends on the drug, the specific condition it is approved for, and in some cases the line of treatment (whether it is first-line, second-line, and so on). A drug that is PBS-listed for one condition may not be listed for another, even if the treating specialist believes it would help.

If a drug is not PBS-listed, it is worth asking whether a compassionate access or expanded access program exists. Pharmaceutical companies sometimes provide drugs at no cost or significantly reduced cost through these programs while awaiting PBS approval or for specific circumstances. Your specialist can apply on your behalf. See the funding treatment guide for more detail.

What questions should I raise with my specialist?

These questions are written in plain language you can bring to your next appointment. You do not need to understand the answers fully before asking. The purpose of asking is to start the conversation.

A good specialist will welcome these questions. If you feel you are not getting clear answers, it is entirely reasonable to seek a second opinion from another specialist with relevant expertise.

1. Has biomarker or molecular testing been done on my condition? If not, would it be appropriate?
2. Are there any immunotherapy or targeted therapy options that might be relevant to my diagnosis?
3. If any of these treatments are relevant, are they PBS-listed or would there be out-of-pocket costs?
4. Are there clinical trials I should know about that involve these treatments?
5. Is there any reason to act on this now rather than wait, given how treatment eligibility can change?

Does private versus public treatment affect my access?

Access to newer treatments can differ between the public and private systems. In the public system, treatment decisions are often made by a multidisciplinary team and follow established protocols. In the private system, specialists have more flexibility but costs can be significant.

If you are in the public system and believe a particular treatment should be considered, you can ask your GP for a referral to a specialist who works in both public and private settings for a second opinion. You can also ask whether your treating team has considered a specific treatment and why it was or was not recommended.

Your health fund, if you have one, may cover some costs associated with private treatment. Ask your fund what is covered before making decisions based on assumed cost.

How do I manage my expectations about these treatments honestly?

Immunotherapy and targeted therapies have produced remarkable results for some people. They have also not worked at all for others. The biology of each person's condition is different, and no treatment works for everyone.

Going into these conversations with clear questions rather than fixed hopes tends to produce better outcomes. You want to understand what the realistic possibilities are, what the side effect profile looks like, and how treatment would affect your daily life and quality of life. Those are the right questions, and you deserve honest answers to them.

If a treatment is unlikely to help or is likely to cause significant suffering without meaningful benefit, your specialist should tell you that clearly. If they do not, ask directly.