Joining a clinical trial in Australia follows the same path almost every time: you express interest, answer pre-screening questions, attend a screening visit where you go through informed consent and have tests done, then start a scheduled series of study visits. Nothing happens to you before you've signed a consent form, and you can stop at any point.
That last sentence is the one most people need to hear twice. You are not locked in.
The rest of this page walks through each stage in order, how long each one takes, who you'll be dealing with, and what will be asked of you. If you're weighing up whether to put your hand up at all, read the benefits and risks alongside this.
Why clinical trials exist at all
Before a new medicine or device can be registered by the Therapeutic Goods Administration and prescribed in Australia, it has to be tested in people. Laboratory work and animal studies can suggest that something is safe and might work. They can't prove it. Only human studies can show whether a treatment helps, how much of it to give, and what side effects show up at what rate.
Trials run in phases, and knowing which phase you're being offered tells you a lot about what to expect:
| Phase | Who takes part | What it's testing | Typical size |
|---|---|---|---|
| Phase 1 | Usually healthy volunteers; sometimes patients | Safety, tolerability, how the body processes the drug | Tens of people |
| Phase 2 | Patients with the condition | Whether it works, and at what dose | Dozens to a few hundred |
| Phase 3 | Patients with the condition | Whether it works better than existing treatment or placebo | Hundreds to thousands |
| Phase 4 | Patients, after registration | Long-term safety and real-world use | Varies widely |
A Phase 3 trial for a condition you already have looks very different from a Phase 1 study in a residential unit. If you're healthy and considering a Phase 1 study, this page is written for you instead.
The seven stages of a clinical trial, in order
1. You find a trial and express interest
Either you find the trial or it finds you: a specialist mentions it, your GP passes on a flyer, you see an ad, or you search a registry. Every trial running in Australia should be listed on the Australian New Zealand Clinical Trials Registry (ANZCTR) or ClinicalTrials.gov. If you can't find a trial on either, ask why before you go further.
Expressing interest is not applying, and it commits you to nothing.
2. Pre-screening (5–15 minutes)
A short set of questions, online or by phone, checking whether you're likely to fit the study's eligibility criteria. Age, diagnosis, how long you've had it, current medications, other health conditions.
It feels intrusive for a first conversation. There's a reason for it, and it's covered in what pre-screening is and why we ask so many questions.
Most people who express interest don't make it past this stage. That isn't a judgement on you. Protocols are narrow by design.
3. The screening visit (1–4 hours, sometimes split across two visits)
Your first visit to the research site. The order matters here, and it's fixed by good clinical practice: consent comes before any study procedure. Know your rights before you sign.
What happens:
- A study coordinator or doctor takes you through the Participant Information and Consent Form (PICF), section by section
- You ask questions. Take as long as you need. You can take the form home and come back
- You sign, and you're given a copy to keep
- Then the assessments begin: medical history, physical examination, vital signs, blood tests, urine sample, often an ECG. Depending on the condition being studied, you might have imaging, lung function tests, questionnaires, or a biopsy
- Some studies require a washout period, where you stop a current medication under supervision before you can continue
Then you wait. Results take days to a couple of weeks, and screening tests knock out a meaningful share of people at this point. Being told you're not eligible after screening is common and it's frustrating. It also means the trial's safety criteria are being applied properly.
Bring to your screening visit: a written list of every medication and supplement you take with doses, your Medicare card, contact details for your GP and specialist, any recent test results or scans you have copies of, and something to do while you wait. Forgetting the medication list is the single most common cause of a delayed screening.
4. Baseline and randomisation
If you're eligible, you have a baseline visit that captures your starting point, then you're allocated to a treatment group. In most Phase 2 and 3 trials this is done at random by a computer, and in blinded trials neither you nor your study doctor knows which group you're in.
This is the stage where the placebo question becomes real. Read will I get a placebo? before you consent, not after.
5. The treatment period
The bulk of the trial. You take the study treatment as directed and attend visits on a schedule set by the protocol, not by how you're feeling.
A typical visit includes vitals, blood tests, a symptom and side-effect review, questionnaires, a tablet or diary count to check compliance, and your next supply of study medication. Visits often run 30 minutes to a few hours. Early in a trial they may be weekly; later they may stretch to monthly or quarterly.
Between visits you'll usually be asked to keep a diary or use an app, take the treatment at set times, report any new symptom or hospital visit promptly, and check before starting any new medication, including over-the-counter ones.
You'll have a 24-hour contact number for the site. Use it. Under-reporting side effects because you don't want to be a nuisance is the most common mistake participants make.
6. End-of-study visit
A final round of assessments, return of any unused medication, and a conversation about what happens next: whether you go back to standard care, whether continued access to the study treatment is available, and what follow-up is planned. Some trials have a safety follow-up call or visit weeks or months later.
7. After the trial
Results go to the sponsor, then to regulators, publications and the trial registry. Getting your individual results back depends on the study. Ask directly at consent whether you'll be told which group you were in and when, because the answer varies and it's easier to establish upfront than to chase later.
How much time does a clinical trial take?
Total commitment ranges from a single day for some Phase 1 studies to several years for long-term Phase 3 trials in chronic conditions. What you should ask for, in writing, before consenting:
- The number of visits and how long each one takes
- The total duration, including follow-up
- Which visits are unavoidable and which have flexibility
- Whether any visit requires an overnight stay
- Whether anything can be done by phone, telehealth or a home nursing visit
A trial that fits your working life is one you'll finish. A trial that doesn't is one you'll withdraw from in month three, which helps no one.
Who you'll be dealing with
- Principal investigator (PI): the doctor responsible for the trial at your site, including your safety
- Study coordinator: usually a research nurse, and the person you'll speak to most. Your main point of contact
- Sub-investigators and site staff: other doctors, nurses, phlebotomists, pharmacists
- The sponsor: the company or institution running the trial. You won't usually meet them
- Monitors: sponsor or CRO staff who visit the site to check the data and, with your consent, review your records
- The human research ethics committee (HREC): reviewed and approved the trial before it opened, and continues to oversee it. Independent of the sponsor
Will it cost me anything?
The study treatment and the tests required by the protocol are provided at no cost to you. Most sites reimburse out-of-pocket costs such as travel and parking, and some studies offer a payment for time and inconvenience, which is more common in healthy volunteer studies than in patient trials.
You should never be asked to pay to take part in a clinical trial. If you are, stop and check the trial's legitimacy.
What isn't covered: your ordinary healthcare unrelated to the study. Ask specifically what happens to costs if you need care for something the study caused. It should be spelled out in the PICF.
Ten questions to ask before you consent
- What phase is this trial, and what's already known about the treatment?
- What are my chances of receiving placebo or the comparator instead?
- How many visits, over how long, and how long is each one?
- What procedures are extra, compared to my usual care?
- What are the most common side effects seen so far, and the most serious?
- Can I stay on my current medications?
- Who do I call at 2am if something goes wrong?
- What happens to my treatment when the trial ends?
- Will I be told which group I was in, and when?
- What are the alternatives to this trial, including doing nothing?
Print that list and take it in. A good study coordinator will be pleased you asked.
Frequently asked questions
Do I need private health insurance to join a clinical trial in Australia? No. Trials are not billed to your private health cover, and the tests and treatment required by the protocol are provided at no cost to you.
Should I tell my GP I'm in a trial? Almost always yes. Ask the site to share the details with them, with your permission of course, and it's in your interest. Your GP needs to know what you're taking before prescribing anything new.
Can I take part if I live in a regional area? Sometimes. Ask about travel reimbursement, telehealth visits, home nursing, or via your GP and whether a site closer to you is also recruiting. Distance is a common reason people withdraw, so be realistic about it upfront.
Do I have to stop my current medication? It depends on the protocol. Some trials require a washout, others allow you to continue. Never stop a prescribed medication on your own to try to qualify.
Can I be in two trials at once? Generally no. Overlapping studies compromise the data and can be unsafe.
Where to start
If you're seriously considering it, do two things this week: write out your full medication list with doses, and write down the three questions you most want answered. Take both to your first conversation with a study coordinator.
One thing to watch for once you're in: the visit that falls at an inconvenient time. Skipped or rescheduled visits are the point where a participant quietly starts to drift out of a trial. If the schedule is becoming unmanageable, say so early. Sites have more flexibility than most people assume, but only before a visit is missed, not after.
View our currently recruiting clinical trials →
Sources
- Therapeutic Goods Administration (TGA), Clinical Trial Notification and Clinical Trial Approval schemes.
- National Health and Medical Research Council (NHMRC), National Statement on Ethical Conduct in Human Research.
- International Council for Harmonisation, ICH E6 Guideline for Good Clinical Practice.
- Australian New Zealand Clinical Trials Registry (ANZCTR) and ClinicalTrials.gov.
Related reading: Are clinical trials safe? · Your rights as a clinical trial participant · Weighing the benefits against the risks · Can healthy people join a clinical trial?