About clinical trials

This information is about clinical trials for lymphoma: what they are, why they are done, how they are carried out, what they involve and who can join them. We have another page about taking part in clinical trials that answers common questions about taking part, as well as a list of questions you might like to ask the clinical trial’s team. 

There is a lot of information on this page. You might want to read it in chunks. You can use the links under ‘On this page’ to help you navigate to the parts that are most relevant to you.

On this page

What are clinical trials?

How are clinical trials designed?

Planning clinical trials

Who can take part in a clinical trial?

What happens at the end of a trial?

What are clinical trials?

Clinical research is research directly involving people to understand health and disease better. There are two main types of clinical research: clinical trials and observational studies.

Clinical trials, or interventional studies, aim to find better ways to treat or prevent different diseases. This page focuses on clinical trials for lymphoma. Trials often test potential new treatments, or new ways of giving treatments, and compare them to the current treatments available. Every new treatment for lymphoma needs to be tested in clinical trials before it can be approved. Clinical trials are the fastest and safest way to find new treatments for lymphoma. 

Dr Chris McNamara and Dr Kirit Ardeshna explain the different types of clinical trials used in lymphoma research.

Clinical trials testing new treatments aim to find out: 

• if the new treatment is safe
• what is the best dose of the treatment
• how it compares to current treatments
• if it has side-effects. 

Not all clinical trials will result in a new treatment. Sometimes the results from a trial do not indicate that the new treatment is more effective or has more manageable side effects than current standard treatments. 

Clinical trials can test:

• a new treatment to see if it works, if it is safe, whether it is better than the current standard treatment, if it can work in combination with other treatments, how it works and how your body processes it.
• existing treatments to compare one treatment with another, comparing different ways of using existing treatments (for example, a different dose or a different way of giving it), or testing if treatments used for other diseases could help people with lymphoma.

Observational studies do not involve giving anyone a treatment or intervention. They might be used to study:

• what causes lymphoma
• the best ways to detect or diagnose lymphoma
• how genetic changes (mutations) in lymphoma cells might be used to design or choose treatments
• the best ways to monitor response to treatment and follow-up after treatment
• how lymphoma affects your quality of life.

This page will focus on clinical trials rather than observational studies.

If you are considering entering a trial that does not involve treatment, talk to your medical team about exactly what is involved.

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How are clinical trials designed?

There are several ways to organise a trial, but regardless of the method used they aim to provide accurate and reliable results. They are also designed to make them as safe and risk-free to participants as possible.

Four important parts of trial design that we will explain on this page are:

• phases of trials
• randomisation
• blinding
• placebos.

Dr William Townsend talks about the difference between early phase trials for lymphoma (phase 1 trials) and those in later phases (phase 2 and 3).

Phases of trials

Clinical trials are organised in phases. More is learnt about a treatment as it goes through the different phases. If a treatment is not successful in one phase, it can’t go on to the next. 

• Phase 1 trials test the safety and side-effects of a new treatment in a small number of people. One of the aims of a phase 1 trial is often to find out what the right dose might be to use in later studies. These are called a ‘dose escalation study’. They start with small doses and increase the dose if the people taking tolerate the treatment. Many phase 1 trials have a dose escalation followed by a dose expansion. Phase 1 trials might be the first time a treatment has been tested in people (known as ‘first-in-human’ trials). They are usually only carried out in people who have no other treatment options.
• Phase 2 trials aim to find out more about the safety and effectiveness of the new treatment in a larger group of people. This is to get a better understanding of its side effects in the short term.
• Phase 3 trials compare the safety and effectiveness of the new treatment (or new way of using an existing treatment) to current treatment in a larger group of people.
• Phase 4 trials are done after the new treatment has been shown to work and it has been licensed (a doctor can prescribe it), to monitor how well it works and any side effects that occur with widespread use.

Phase 1 and 2 trials are sometimes called ‘early phase’ trials. Phase 3 and 4 trials are sometimes called ‘late phase’ trials.

Randomisation

When trials compare at least one treatment against another, they are often randomised. Randomised trials are the best way of collecting reliable evidence about a new treatment. Instead of a doctor choosing which treatment you have, you are randomly assigned to different treatment groups. These are sometimes called ‘treatment arms’. If you are in a randomised trial, you can’t choose which treatment you have and neither can your doctor. The treatment you are given is down to chance. You may be allocated to the ‘control group’. People in this group are either given the current standard treatment, a placebo or no treatment at all.

To make sure any differences in results are due to the treatment and not another factor, researchers aim to make the treatment arms the same in all other ways. This means that people in each treatment are matched for things like age, gender and stage of lymphoma.

Blinding

In some trials, you do not know which treatment you are having. This is called a ‘blind’ trial. If your doctor doesn’t know either, the trial is called ‘double-blind’. Blinding is used to remove any expectations you or your doctor might have about the treatment. Expectations could affect the results of the trial because people can’t help being influenced by knowing what the treatment is. The trial organisers keep a record of who is having which treatment so they can tell your doctor if any problems occur.

Placebos

A placebo is a dummy treatment. It doesn’t have any active medication in it so will not help the disease but will also not cause any harm. It is used to make sure that the results of a trial aren’t affected by whether or not participants know they are having active treatment.

Many lymphoma trials do not use placebos. If they do, placebos are used in addition to standard treatment. You don’t have placebo treatment on its own. For example, participants in a placebo-controlled trial might be treated with either:

• standard treatment plus the new treatment
• standard treatment plus a placebo that looks the same as the new treatment.

If you take part in a trial that uses placebos, your trial team will tell you. However, you won’t know whether you are having the placebo or active treatment.

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Planning clinical trials

Setting up any trial usually takes a long time. Clinical trials in the UK are governed by strict laws. These laws protect the people taking part and help to ensure that trials are as safe as possible.

Organising a trial usually involves the following process:

• Making a proposal: All trials start with an idea or question that researchers want to answer. Clinical trials are designed by individuals or organisations to try to answer this question. This might be by a university or a pharmaceutical (drug) company.
• Developing a protocol: Every trial needs a document that describes the study in detail. This is called the trial ‘protocol’. The doctors and nurses treating you have to follow the procedures described in the protocol to make sure everyone who participates in the trial is treated in the same way. The protocol includes information on:
  • why the research is needed
  • who is able to take part
  • how many people are needed for the trial
  • the treatments, tests and methods involved
  • how participants will be monitored and for how long
  • and when the trial will end.
• Getting funding: Trials are very expensive. Funding has to cover costs for research staff, administration, drugs and tests, hospital stays, analysis of the results and the costs of following-up participants, sometimes long after treatment has finished. Cancer trials in the UK are usually funded by a pharmaceutical company, a national charity (for example Cancer Research UK or Blood Cancer UK) or a government organisation. In most cases it comes from a combination of sources.
• Getting a sponsor: Every trial needs to have a sponsor. This is usually an organisation or an institution, but it can be an individual. They are there to manage the trial, and to ensure that the research team carries out the trial correctly, following all the regulations.
• Getting approval: All clinical trials must be approved by an independent ethics committee and by the Medicines and Healthcare products Regulatory Agency (MHRA), a government organisation that regulates the use of medicines in the UK. These agencies look at the protocol carefully to make sure the researchers are working in the participants’ best interests.

Once the protocol has been approved and funding has been secured, investigators can begin to find people to take part in the trial. This is called ‘recruitment’. If your doctor thinks you could be suitable for a trial they might suggest you take part. You can choose not to get involved. Your decision won’t affect the care or treatment you receive outside the trial.

If you do consider taking part in a trial, you might want to read some of the advantages and disadvantages of taking part. Take time to think about all the information you get. Ask your doctor questions to make sure you understand what is involved. You can show the information to someone else, such as a family member or your GP.

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Who can take part in a clinical trial?

In order to take part in a clinical trial, you must meet a strict set of criteria. These ‘eligibility’ criteria help to make sure that everyone taking part in the trial are like each other in terms of characteristics such as age, type and stage of lymphoma, general health, and previous treatment.

• Inclusion criteria set out who can take part in the trial. For example, the type of your lymphoma, the stage of your lymphoma and whether you have already had treatment or not. The criteria also usually give an age range for participants.
• Exclusion criteria set out who can’t take part in the trial. For example, certain previous treatments might interact with the study drugs so you can’t join the trial if you’ve had them. Other criteria relate to safety, so if you have other medical conditions, you might not be able to take part. Pregnant and breastfeeding women are normally excluded from clinical trials to prevent harm to the baby.

Some trials are available for children under the age of 16 to take part in. You might find our information about lymphoma in children helpful – we include information about giving consent for children to receive treatment. 

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What happens at the end of a trial?

After you finish treatment as part of a trial, there is usually a long period of follow-up, often several years. The trial team is interested in long-term as well as short-term effects of a treatment. As part of follow-up, you attend the hospital regularly for tests and a check-up. Details of what is involved are included on your information sheet.

It can take several years before the results of a clinical trial are available. This is because it takes time to recruit enough people, treat them according to the trial protocol, and follow them up afterwards. Researchers also need to analyse the results to work out what the outcome of the study is. Results are usually reported at major medical conferences and in medical or scientific journals. For some clinical trials, people who took part are sent a results information sheet. 

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