What is a clinical trial?

A clinical trial is basically a scientific study that involves people. The aim of clinical trials is to investigate whether a medicine is reliable, safe and effective for the treatment of a particular disease or condition. Clinical trials are often carried out by a pharmaceutical company in collaboration with independent investigators (doctors).

Clinical trials allow researchers to measure the extent of the medicine’s effect, so they can predict with some confidence how much benefit patients with the same condition will get, and whether there are any potential side effects doctors need to warn patients to look for.

What happens in clinical trials?

A clinical trial can be designed in a number of ways. In randomised controlled clinical trials, large numbers of people are recruited to participate in the study. The people who have been recruited are divided by random allocation into two or more groups, so that the groups are similar in terms of age, sex, illness, and other factors that could have an impact on the study results. Each group is given a placebo (a tablet which is not active medicine) or a standard treatment for the disease.

You may have read that many clinical trials are ‘double blind’ trials. This means that during the course of the trial none of the participants, clinical trial staff/study staff know who is taking what, until the end of the trial, and so no one can affect the outcome of the trial in any way. The participants are given study medicine or the placebo/standard treatment, to take in the same way as their family doctor would request. At the end of the trial, the results from the people taking the study medicine are recorded and then compared with the results of the people taking the placebo/standard treatment, using statistical measures. This way researchers can get an accurate picture of what people can expect if they begin taking the medicine.

There is a method called “unblinding” which shows the researchers what trial medication the participant is taking should they need to know because of a side effect.

What are the phases in clinical trials?

There are various phases involved in the development of a new medicine, from the laboratory to the local pharmacy where it is available to consumers.

Initial Testing: Following the initial development of the medicine, which can take several years, it is extensively tested in the laboratory and on animals to work out its actions, to determine what the side effects might be, and to make sure it is not harmful.

After the initial development and testing, clinical testing begins. This requires Ministry of Health approval and Ethics Committee review. Clinical trials are divided into three phases of study, each phase involving greater numbers of people.

Phase I: The trial focuses on the safety of the medicine. Studies are normally conducted on healthy volunteers, usually numbering between 20 to 100 people. Researchers study the effective and tolerated dose and how the medicine is absorbed, broken down and eliminated by the body, as well as identifying any side effects at different doses. This phase generally lasts several months. More than two-thirds of medicines progress past phase I.

Phase II: Focuses mostly on the effectiveness of the study medicine in treating the intended disease. In this phase there is also some emphasis on side effects and risks in participants with existing health problems. Generally, a few hundred volunteers participate in phase II trials, which take longer than phase I trials. Only about one third of medicines successfully complete this phase.

Phase III: In this phase the focus is on safety, effectiveness and determining the right dose to treat the disease. Several hundred people with the disease in question may participate. By using such large numbers of people, less common side effects will emerge. Most of the medicines that successfully complete phase II also complete phase III.

How do researchers know the medicine won't have unwanted side effects?

As mentioned above, part of the purpose of clinical trials is not only to assess benefits but also to see if any unwanted side effects emerge, and how severe or common these are, as well as the benefits. Any side effects that occur in the group taking the study medicine are compared to the side effects seen in the placebo group or standard treatment group.

Most of the side effects in the placebo group are due to unrelated illnesses such as stomach upsets and colds. Only by comparing the two groups can the researchers determine whether an unwanted effect is due to the medicine or an unrelated illness.

What happens with the results?

The final results of the clinical trials are reported in the medical journals without individuals being identified.

They are available for doctors, so that they can make scientifically-based assessments of the benefits and risks for each patient. A collected summary of the results can be obtained, however this may be some time after the trial is completed. The data may be used to obtain permission from the Ministry of Health to market the product in New Zealand. If you have participated in a study, a summary will be sent to you at your request.

Who is involved in clinical trials?

A volunteer will be invited into a study if they meet the specific criteria for that study, and pass all pre-trial assessments. The doctor who manages a study is known as the Investigator. The Investigator is responsible for the overall management of the study.

Each Investigator is supported by a team comprising co-investigators (other doctors), a study coordinator, research nurses and other support staff who are responsible for your medical care while on the trial and will always put your safety and interests first. Each person has clearly defined responsibilities in the running of a trial. You will be given the name of the person you need to contact for appointments or advice.

How are clinical trials managed?

All parties (investigators, study co-ordinators and pharmaceutical company employees) involved with the development and testing of the study medicine must follow the study protocol. The protocol sets out in detail the process and design of the study, the treatment(s) to be used and the measurements that will be required.

In New Zealand all trial protocols must be approved by the local ethics committee, which may be contacted if you have any concerns. To gain advice with regard to volunteer rights in a clinical study, you may contact a Health & Disability Consumer Advocate on 0800 11 22 33.

What do volunteers have to do if they participate?

As participants in a clinical trial, volunteers have responsibilities.

Before agreeing to participate in the trial the should read the participant information sheet and understand what participation in the trial will involve. Volunteers are encouraged to ask the Investigator any questions necessary to fully understand the study. Volunteers are then asked to sign a consent form.

Participation in clinical trials is voluntary. If a volunteer decides not to participate, it will not affect their ongoing healthcare. If they do decide to participate, they may withdaw at any time without having to give a reason and this will not affect their future care.

By signing the Consent Form volunteers are agreeing to participate in the study.

It is important that volunteers take the trial medication as prescribed by the study staff. This involves taking the study medicine at the requested times and attending regular outpatient appointments at ACS. During these appointments, volunteers will be asked to bring their medicines with them to ensure they are taking the correct dose with the specified treatment.

When a pharmaceutical company sponsors a trial, ACC does not cover volunteer participation. The drug company running the trial will provide compensation. The Investigator can provide further details if required.

Are there any risks?

There is always some risk associated with taking any medicine and there will be an additional risk in taking any new medicines.

If a side effect does occur during a clinical trial and it is decided that it is due to the study medicine, you may choose to withdraw from the study or the doctor may withdraw you from the study. Sometimes the trial is stopped.

Are there any other checks in clinical trials?

During a clinical trial a monitor checks all the data. The pharmaceutical company employs a monitor to manage the study and to check that all evaluation data are correct and entered without errors. This is to ensure the doctors and medical team are following good clinical practice guidelines.

All clinical trials may be subject to an audit, which may be undertaken by either local regulatory authorities (including Ethics committees), the pharmaceutical company, or possibly by the Food and Drug Administration (FDA).

Will I be paid for taking part?
  • For healthy volunteer studies you will be reimbursed for your time and inconvenience at the end of the study. Full payment is conditional on completing the study and complying with the restrictions.
  • If you are receiving a benefit or allowance from a government agency, there may be implications for this if you participate in the study. You may wish to discuss this with your case manager prior to taking part. The payment advice you receive will state that you were paid from the admission visit until the final follow-up visit. ACS staff are not qualified to provide advice on tax issues.
  • If you are withdrawn from the study for medical reasons, having received trial medication, you will receive payment in full. If you withdraw for any other reason you may not be entitled to full payment but you will receive a portion of the payment, depending on how much of the study you have completed.
  • Once you have been accepted onto a study you will be offered taxis to get to and from your visits. There is no parking available at ACS. Metered parking is available on Grafton Road and the Auckland City Hospital carpark is nearby so we can also help with parking and mileage if that works better for you. If you live outside Auckland, we will advise you on your travel payment entitlement.