One of the world’s leading clinical trials programs

As a world-leading cancer centre, The Princess Margaret is responsible for producing the evidence that promising new drugs and newly-proposed treatments are more effective than the drugs and treatments currently being used.

The difficulty and complexity of this responsibility is daunting when you appreciate that one patient’s lung cancer can be very different than another’s.  Our challenge is to determine not only if a new drug or treatment approach is more effective, but precisely who it is more effective for. 

Clinical studies produce the needed evidence, and must be conducted with great care and rigour. Our cancer centre has built a strong reputation for conducting and accurately reporting the results of clinical studies, and is the only cancer centre outside of the U.S. to hold a contract with the U.S. National Cancer Institute that allows us to participate in early phase cancer clinical trials, and therefore to have rapid access to agents in development.

The Princess Margaret is currently conducting more than 600 clinical studies, and is a global leader in study participation (1 in 5 new patients is enrolled in a study). The cancer centre hopes to double the participation rate in trials so promising new treatments are available to as many patients as possible.

The scientists and researchers working in our laboratories and our clinicians treating patients do not work independently, but rather collaborate to take learning from the laboratory and apply it in the clinic with patients, and vice versa. Clinical trials are one of the key areas where this collaboration between researchers and clinicians takes place.

The Princess Margaret is fortunate to be located at the heart of a large cosmopolitan city, which makes it ideal for clinical trials. Dr. Mary Gospodarowicz, head of the Cancer Program for The Princess Margaret, says that in addition to being able to draw from a large population that is ethnically diverse, “The Princess Margaret has the internal breadth and depth to make it one of the most comprehensive cancer centres in the world. There are very few cancer situations that we are not equipped to treat.”

Almost two-thirds of the clinical trials test new drug treatments and are run by the department of Medical Oncology, while the remaining trials are run by the departments of Radiation Oncology, Surgical Oncology and Supportive Care.

Clinical Trial Phases

Clinical trials that involve new drugs generally involve four phases of testing before the drugs can be marketed and used outside of strict testing situations. A drug is usually approved for sale by the national regulatory authority after successful completion of Phase III.

Phase I trials are the first stage of testing a new drug in humans. It is a stage designed to assess the safety and tolerability of a new drug. Usually the drug is administered to a small sample of 20 to 50 people in groups of three to six at a time, with very careful monitoring by fully trained health care professionals. This is the phase when the appropriate dose (and frequency of use) is determined.

With the initial safety of a drug confirmed in Phase I, Phase II trials are performed on larger groups of patients with a focus on determining the effectiveness of the drug.

Phase III trials are typically randomized and involve multiple hospitals/facilities. ‘Randomized’ means that each patient in the trial is randomly assigned to receive either the test drug or the current ‘standard of care’ for their type of cancer. The latter group is called the ‘control group’. The size of each group is typically in the range of 300 to 3,000 people. These trials are expensive, time-consuming and challenging to set up, but if the results are positive, a Phase III trial is considered a definitive assessment of a drug’s effectiveness.

Below is a diagram that shows the approximate timeline involved in developing and testing a new drug.

Phase IV trials often have different objectives. They can be testing the long-term safety of the drug, testing the drug against different populations (e.g., people with specific health conditions) or testing the drug in combination with different drugs.

It is important to note that not all clinical trials result in moving a new treatment or drug forward. In fact, despite the best preparation and optimism for a potential new treatment, there are many that do not get past phase I. However, without many trials, there would not be the breakthroughs that are needed for cancer prevention and treatment.