Targeted treatment targets the changes in cancer cells that help them grow, divide, and spread.

What is targeted treatment?


Targeted treatment uses medicine to target specific genes or proteins either inside cancer cells or on their surface. 

Each medicine blocks a specific ‘target’, for example, a damaged gene or protein, on or within a cancer cell.

Blocking these targets can kill cancer cells or slow their growth. The signs and symptoms of cancer reduce or disappear, and damage to normal cells is minimal.

Cancer is a disease of the body's cells. It starts in our genes. Our bodies are constantly making new cells, a process controlled by certain genes. Cancers are caused by damage to these genes. As the damaged cells replicate a lump or tumour is formed. 

Tumours can be:

  • Benign - not cancerous. These do not spread to other parts of the body.
  • Malignant - cancerous


Visiting the pharmacy
Visiting the pharmacy
Visiting the pharmacy

Types of targeted treatment

There are different types of targeted cancer treatments, such as monoclonal antibodies or small-molecule inhibitors.  


For more information about specific medicines, go to Appendix 1 of our booklet on chemotherapy, immunotherapy, and targeted treatment.  
Chemotherapy, Immunotherapy, and Targeted Treatment booklet


What is a biologic medicine? 

Sometimes targeted treatments are called biologic medicines. These are produced by a living organism, like a bacteria, yeast, or cell in culture. This makes biologics different from standard medicines which are created chemically. An example of a biologic is trastuzumab used to treat HER2 positive breast cancer. 

What is a biosimilar? 

Once the licence for a brand-new medicine no longer applies, other drug companies can produce their own very similar version of a targeted treatment. In the case of a biologic, the second version is called a biosimilar. Biosimilars must show they work in the same way, and are as safe and as effective as the biologic. As an example, Pharmac is considering making biosimilar Herzuma available to replace Herceptin. Biosimilars are more cost-effective which means more people can get access to targeted treatment, it’s more affordable and there are more treatment choices. 


See Canopy Cancer Care's video below for more about biologic and biosimilar medicines.

Video Link:

How targeted treatment works

Targeted treatment medication travels through the bloodstream.

Each medicine blocks a specific target, for example, a damaged gene or protein, on or within a cancer cell.

Blocking these targets can kill cancer cells or slow their growth. The signs and symptoms of cancer reduce or disappear, and damage to healthy cells is minimal.

When is targeted treatment used?

Targeted treatment only works if a cancer cell has the gene or protein that the medication is trying to block – so it isn’t offered to everyone.

Targeted treatment may be used:

  • after surgery to destroy any cancer cells that are left
  • to treat advanced cancer that hasn’t responded to other treatment
  • to try to stop the cancer from coming back
  • to treat cancer that has come back 

Your treatment team will offeryou the best treatment based on the type and stage of cancer as well as your general health.

This means that even if someone else has the same cancer type as you, you may receive different treatments.

Before any treatment begins, make sure that you have discussed and understood your treatment team's advice. You can ask for a second opinion if you want one.

Side effects of targeted treatments

The side effects you may have will be different depending on what type of targeted treatment you have.

Common side effects are:

  • a rash that looks like acne on the face, scalp or upper body
  • tenderness and blisters on the palms of your hands and the soles of your feet
  • skin problems including dry, flaky skin and sensitivity to sunlight
  • fever
  • tiredness
  • feeling sick (nausea)
  • diarrhoea
  • heavy bleeding
  • high blood pressure

Less common side effects are:

  • increased risk of infection
  • changes in how the heart, thyroid, or liver works

Using other medications or treatment

When targeted treatments are used with other medicines or supplements (e.g. vitamins and herbal medicines), it can cause harmful side-effects.

It is important to let your treatment team know about any other medicines or supplements you are taking.  This includes traditional medicines.

It is also a good idea to talk with your treatment team before having any vaccinations.

Using complementary or traditional healing

Sometimes people with cancer might think about using complementary therapies or traditional healing.

Some alternative, complementary and traditional healing methods may react with the treatment you receive and cause harmful side-effects.

It is important to talk to your treatment team about any other therapies you’re using or thinking about because they may interfere with hospital treatment.

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Last updated: August 7, 2023