Taking part in a clinical trial: What you must know

A clinical trial may target different participant profiles, depending on its Phase. Phase I clinical trials usually invite a reduced number of healthy volunteers to assess the safety of an investigational medicinal product. The number of required participants increases in subsequent phases, where participants must have the disease for which the experimental treatment is being assessed.

A person may decide to participate in a clinical trial for several reasons, such as:

• To have the chance to play a more active role in disease discovery, treatment and prevention.
• To have access to new investigational drugs to treat their disease before they are commercially available.

Participation in a clinical trial is a personal, untransferable decision, which must be thoughtfully made based on all the information received. Before enrollment in a clinical trial, the participant will be verbally informed by one of the investigators and will receive a document called “Patient Information Sheet”, which must be read carefully. This document describes the trial, potential risks and benefits, as well as the participant’s rights and obligations. In addition, before making a decision, the participant must ask all the questions required to clarify any potential doubts. If deemed necessary, the patient may postpone his/her decision to another day, after discussing the information with someone he/she trusts.

When participation is agreed, after meeting inclusion criteria and because the information received is considered satisfactory, the document called “Informed Consent” must be signed both by the participant and the investigator who has provided all the information.

It should be noted that, upon deciding to take part in a clinical trial, the participant assumes a series of responsibilities, such as attending study visits and following the instructions received. But the participant must also know that he/she may leave the study whenever he/she may consider it necessary, without giving any reasons and without this affecting any subsequent medical care to treat his/her disease.

It is also important to bear in mind that a participant may be withdrawn from the trial by any of the investigators, whether for safety reasons or because they think that the participant is not following the established procedures. In either case, the participant will be given an adequate explanation of the reason for withdrawal.