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“I would absolutely recommend women to take part in trials if they feel it is right for them. I was very keen to take part in it because I want to try and increase the different drugs that are available for use with ovarian cancer.”

Find out about ovarian cancer clinical trials – what they are, how they work and how you can find out more. 

What are clinical trials?

Clinical trials are research studies that investigate potential new medical treatments and procedures and compare them to the current standard treatments. 

How do clinical trials work?

Drugs and treatments are usually assessed in three phases before they can be considered as a standard treatment option. Each clinical trial phase is designed to answer a specific set of questions about a new drug or treatment, which means there are strict guidelines about who can participate.

Phase I

This is the first time the treatment has been tested outside the laboratory. A small number of people - around 30 or fewer - who have no standard treatment options available, are chosen to participate. 
The aim is to find a safe dose of the treatment and look at the possible side effects. If the treatment is safe and appears to have a positive effect, it will go into Phase II.

Phase II

This builds on the findings from Phase I, improving knowledge of the potential side effects of the treatment and the best dose of the treatment to give. 

It usually involves up to 100 people and looks at which type of cancer the treatment might work best for. If tumours respond to the treatment (either by slowing down growth or reducing in size), it moves to Phase III.

Phase III

This phase recruits the largest number of participants with hundreds or even thousands of people taking part, often from hospitals across the country. 
It compares the new treatment with a standard treatment and will look to see if the new treatment improves overall survival or progression free survival (how long someone stays free of cancer). 

What are the benefits of joining a clinical trial?

Many women view taking part in a clinical trial as a very positive experience. Some of the benefits include:

  • Getting a new treatment before it is widely available.
  • Being one of the first to benefit if the drug or treatment works.
  • Receiving additional monitoring and care – you will need to attend regular tests and check-ups.
  • Helping advance medical knowledge for the benefit of women now and in the future.

Often, clinical trials are randomised, so you will not know whether you are receiving the new or standard treatment. However, research has shown that taking part in a trial can be beneficial, even if you do not have the drug or procedure being tested. This could be because trials involve additional care and monitoring at the hospital. 

You also need to consider that new treatments are not always better than standard treatments. The new drug or treatment might not work for you and sometimes there are unexpected side effects. 

As trials compare new treatments with standard treatments, you may be selected to receive either the new treatment or the standard treatment. So by agreeing to be in a trial, it does not necessarily mean you will receive the new drug being tested. 

How do I find out about clinical trials?

Speak to your oncologist, who should be able to tell you about suitable trials in your local treatment centre. If there isn’t a trial, they may be able to give you information about trials in other hospitals, if you are willing and able to travel.

You might want to ask about:

  • What trials are you eligible for at your treatment centre?
  • If you're willing and able to travel, what is available at another centre?
  • What is the aim of the trial?
  • What is the evidence that this new treatment might be effective?
  • What are the possible risks and benefits of taking part?
  • What taking part would involve compared to not taking part

Remember, if you are suitable, it is your decision whether or not to join a clinical trial.


You can also find out about trials across the UK by visiting our Clinical Trials Information Centre.

Having discussed the possibilities for treatment with your oncologist, you may want to seek a second opinion, either at your current hospital, or one which is more involved in research and trials. Your Clinical Nurse Specialist (CNS) should be able to advise you on how to get a second opinion.

How do drugs get approved for use on the NHS?

A drug is given a license by the European Medicines Agency (EMA) or the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK once it is deemed safe to use in a certain group of patients, and has shown to be of some benefit. 

Drug manufacturers generally submit applications for licenses once the results of clinical trials are published. This process can take up to a year.

Once a drug is licensed, the National Institute of Health and Care Excellence (NICE) and the Scottish Medicines Consortium will, if asked, assess whether the drug should be used by the NHS. 

They look at the clinical and cost effectiveness of the drug. In other words, does the drug in question work better than standard treatments offered (either for all patients, or for a particular group of patients)? Is the price to the NHS acceptable for the amount of benefit seen?

This process can take some considerable time, and countries within the UK may reach different conclusions. 

This means it can take up to two years, or more, from results of trials being announced to the drugs being approved for use on the NHS.


The information on this page is approved by the Information Standard scheme to ensure that it provides accurate and high-quality information.

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Last reviewed: November 2016
Next review: October 2019