What are clinical trials?

Research & Insights

Clinical trials: an explainer

Everything you need to know about clinical trials. And, if you’re interested, how to join one.

Stephanie Osfield
May 2019

If a doctor prescribes medication to treat pneumonia or a surgeon uses keyhole surgery for a hip replacement, those choices are likely informed by the results of clinical trials.

Clinical trials are medical research studies that aim to find a better way to prevent, diagnose or manage a particular condition. The trials involve patients to test new treatments for safety and effectiveness.

"If a clinical trial proves that a treatment is more effective than existing options, it may become the new standard treatment for patients in the future. A trial can also identify any risks and side effects of a treatment and help work out the optimal doses of a medication," says Professor Sanchia Aranda, CEO of Cancer Council Australia.

According to Prof Aranda, in the area of cancer alone, clinical trials helped determine where new immunotherapy treatments are most effective. And imaging techniques like mammograms, ultrasounds and MRIs are available because they have been proved effective and safe via clinical trials.

Types of trials

In Australia, the Therapeutic Goods Administration (TGA) regulates health products to make sure they’re safe and do what they claim to do. The TGA has a very high bar for approving new medications and treatments, and usually multiple human trials are required. Researchers may have spent years developing and testing the treatment before it even gets to the clinical trial phase.

A phase 1 clinical trial includes a small group of people to test safety. For example with a drug, it may look at its dose, how it’s given to people and if there are any side effects. The people in the trial may not have the condition the treatment is developed for.

A phase 2 clinical trial may include a larger group of people and checks if the treatment does what it’s intended to do. The people in the trial usually have the condition the treatment is developed for.

Phase 3 clinical trials include more people again. They’ll compare the trial treatment to other treatments and monitor side effects.

"Phase 3 trials usually eliminate biases by randomly selecting participants and ‘controlling’ for other factors, such as lifestyle," Prof Aranda explains.

The gold standard is a ‘double blind placebo’ trial. "These involve several groups of patients, and they don’t know if they are receiving a placebo or the real treatment," Prof Aranda adds.

After the treatment has been registered by the TGA, phase 4 clinical trials establish long-term benefits, risks and other potential uses.

Taking part in clinical trials

Healthy people may be involved in trials to help others.

Or people with a condition may get involved in trials to access a treatment before it’s widely available, or to help researchers gain a better understanding of their condition, reports Australian Clinical Trials. You may also get closer management of your condition.

Risks of taking part may include side effects and the treatment not being as effective as standard treatments. It could also take up a lot of your time.

"Before you commit to any trial you should always ask about the potential risks and benefits and check in with your doctor or specialist," says Dr Chris Zappala, vice president of the Australian Medical Association.

You’ll also need to know about the study’s purpose, duration, time commitments, procedures and tests involved and key contacts, says the Consumers Health Forum of Australia. You can usually leave a trial at any time.

Ask your GP or specialist for information. Clinical trials often take place in large teaching hospitals. The online Australian New Zealand Clinical Trials Registry also lists current and upcoming trials.

Evrima, a participant in the 2019 HCF Catalyst accelerator program, connects people, doctors and researchers together to raise awareness of clinical trials and make it easier for people to register their interest. They focus on trials for lifestyle and chronic diseases that people would typically visit their GP for, such as asthma, diabetes, obesity, pain and osteoarthritis.

"There are also many good news stories of people with no other treatment options who live longer or far healthier [lives] due to the benefits of a cutting edge new treatment they try in a clinical trial," Dr Zappala says. "These uplifting and encouraging results don’t just help those involved, they also benefit others in the short and long term."

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