The following information provides general information about clinical trials in patients with cancer. 

What is a clinical trial?

Clinical trials are studies that test new ways to prevent, detect and treat diseases like breast cancer.

Many standard therapies commonly used in cancer treatment today began as drugs in clinical trials. 

There are generally three phases involved in clinical trials. 

Phase 1 – This is a very early trial of a new therapy, generally on 20-40 patients, after extensive pre-clinical tests in animals in the laboratory. 

This usually involves steadily increasing doses in a small group of patients, provided there is no major toxicity. 

The aim is to gauge safety side effects and what doses can be achieved. 

Patients who take part often have exhausted other treatments and are willing to see if the new drug helps though they know there are no guarantees and the new treatment could have side effects. 

Phase 2 – This involves more patients and to see whether not and whether the drug has promising effectiveness in that specific cancer and to confirm side effects. It often involves a control group.

Phase 3 – This is a large trial (often international) involving hundreds and up to several thousand patients. These are generally regulatory trials, testing the proposed new treatment against the standard usual treatment in head to head comparisons. Sometimes, the new treatment may not be better than an older standard treatment. If successful however, the pharmaceutical company can apply for a licence to market the drug. 

Phase 4 – Safety studies during sales

This assesses drug safety after sales – these studies delineate benefits, risks, and optimal use. They will continue for the drug’s lifetime and period of active consumer use. 

Why participate in a clinical trial?

  • A clinical trial offers patients a chance to receive a treatment that might otherwise be unavailable and costly. 
  • Often patients feel that by engaging with medical research they better understand their disease, and patients have access to the latest medicines before they go to market; medicines that may otherwise cost hundreds or thousands of dollars a month. 
  • Patients have consistent contact with medical specialists. 
  • Results from a clinical trial that you are involved in may help others in the future and are key to moving the field of cancer research forward.

What you need to know 

  • Remember before participating in any medical trials make sure: 
  • That the trial has been accepted by an independent ethics committee – usually committees are attached to teaching hospitals or local area health services 
  • That you have been given time to assess the trial and to read and understand the informed document. 
  • That you have been given an opportunity to ask questions about the trial. 
  • That you know what commitment is involved in terms of time, visits, parking and costs. 
  • That you understand possible risks and benefits. 


Professor Sudha Rao