Last updated, March 2008.

Next due for update, March 2009.

Clinical trials are needed to see if a medicine is safe and works. This factsheet provides a brief introduction to the types of clinical trial that people with HIV might be asked to join. There is also information on how a trial is organised and what your rights and responsibilities are if you join a trial.

HIV and clinical trials

Clinical trials involving people with HIV are currently testing treatments in five areas:

**Treatment against HIV to stop or delay it damaging the immune system.

**Treatment to boost the immune system.

**Treatment against other infections.

**Treatment to stop infections developing – often called prophylaxis.

**Vaccine against HIV and other infections.

How trials are organised

A new treatment is first tested in the laboratory. If these results are promising clinical trials are started in humans. There are a number of stages or phases to a trial depending on how far advanced research into a drug has progressed.

 **Phase I: This stage is to see if a drug is safe to be tested in humans and what the maximum safe dose is.

**Phase I/II: This stage is to see what the maximum safe dose is.

**Phase II: This stage looks at the effectiveness of a drug in the short-term, normally about six months.

**Phase III: This stage normally lasts at least a year and compares the next drug to an existing treatment or a dummy treatment called a placebo.

Randomisation

If a trial is comparing two treatments it is normally randomised. This means that people are selected at random, normally by a computer, to take one of two treatments. This way researchers can be sure that treatments are being tested in people who have similar characteristics.

'Blinding'

Many trials are ‘blinded.’ This is to make sure that your or your doctor’s expectations don’t influence the results of a study. If a study is ‘double blinded’ it means that neither you nor your doctor knows which treatment you are taking. If it is ‘single blinded’ to means that you do not know which treatment you are taking.

Comparison studies

In these studies, one group of people will receive a new treatment, the other group will be given the treatment that is in current use.

Placebo-controlled trials

If there is no current treatment, the study will be a placebo-controlled trial. This compares the safety and effectiveness of the new treatment to a dummy placebo. You won’t know if you are taking the active treatment or the placebo.

Dose studies

Some trials compare different doses of drugs. Sometimes there studies are ‘blinded.’

Open label studies

In these trials both you and your doctor know what treatment is being given.

Information about a trial

All trials have what’s called a protocol. This sets out its aims and objectives. Trials also have rules about who can and cannot join. These are called inclusion and exclusion criteria.

You should always be given written information about a trial. You should read it carefully and ask questions if there is anything you don’t understand. 

Before you join a trial you have to give your written consent. You should only give this after important facts about the trial have been explained, including the possible risks and benefits.

Rights and responsibilities

You should not have pressure put on you to join a trial. Saying no should not affect the standard of care you receive.

If you do join a trial, you can withdraw at any time without having to give a reason.

You should be given details of how to contact somebody if there is an emergency.

You also have responsibilities if you join a trial. For example, taking your treatment as instructed and keeping clinic appointments. It’s also important to tell your doctor if you experience any changes in your health or develop symptoms.