Health research is a key tool for improving both the quality and life expectancy of citizens. It also plays a fundamental role in enhancing the general well-being and economic development of society by advancing the prevention, diagnosis, and treatment of diseases.
Human research is irreplaceable when it comes to obtaining reliable evidence on the safety and clinical efficacy of new drugs. However, before any treatment can be administered to humans, preclinical studies must be conducted to gather initial data on safety and pharmacological activity—these typically include laboratory tests and/or animal studies.
Once the preclinical phase is successfully completed, clinical trials are initiated with the goal of obtaining regulatory approval and, eventually, commercializing the new drug. This research must always be conducted under the highest safety standards for the individuals involved. Therefore, all clinical trials must be authorized by the Spanish Agency of Medicines and Medical Devices (AEMPS) and must receive a favorable opinion from a Research Ethics Committee for medicinal products (CEIm).
WHAT IS A CLINICAL TRIAL? A clinical trial is a scientific study conducted in humans to evaluate the safety, efficacy, and potential benefits of new treatments, medications, or medical procedures.
WHY ARE CLINICAL TRIALS IMPORTANT? Clinical trials are essential to ensure that new treatments are both safe and effective before they can be approved for widespread use in medical practice.
PHASE I: The treatment is tested in a small group of healthy volunteers to evaluate its safety, determine a safe dosage range, and identify possible side effects.
PHASE II: The treatment is administered to a larger group of patients to assess its effectiveness and further evaluate its safety profile.
PHASE III: The treatment is compared to the current standard of care in a large patient population to confirm its efficacy, monitor side effects, and collect information for regulatory approval.
PHASE IV: Conducted after the treatment is approved and on the market. It gathers additional information on long-term effectiveness, benefits, and any rare or long-term side effects.
A clinical trial is a type of research carried out with people to evaluate the safety and effectiveness of a treatment, medication, or medical procedure. These studies are essential to determine whether a new therapy provides more benefits than risks.
Clinical trials generate high-quality evidence that helps improve current treatments, develop new ones, and ultimately contribute to preventing, alleviating, or curing diseases. They also play a key role in improving the quality of life of the population.
To be approved by regulatory agencies, a new drug must go through several clinical trial phases. Each phase has a specific purpose and builds upon the results of the previous one. These phases are known as Phase I, II, III, and IV.
Focuses on safety. A small group of healthy volunteers receives the drug at low doses, which are gradually increased. The main goal is to determine the safest way to administer the treatment and identify the most appropriate dosage range.
Involves patients who have the condition the drug is intended to treat. This phase assesses the treatment’s effectiveness and continues to monitor safety. Some studies may include a placebo group—a substance with no active ingredient—for comparison.
Includes a larger patient population and compares the new treatment with standard therapies. It confirms effectiveness, identifies side effects, and gathers all necessary data for regulatory approval and marketing authorization.
Conducted after the drug is approved and available to the public. These studies monitor long-term safety and effectiveness in real-world conditions. They may also explore new uses or dosing strategies for the drug.
Participation in a clinical trial is always voluntary and depends on the specific criteria of each study. Some trials are open to healthy volunteers, while others involve patients with a particular condition.
In studies with patients, the treating physician usually informs the individual about the possibility of joining the trial. The physician will explain the purpose of the study, its procedures, potential risks and benefits, and any other relevant details.
If the patient meets the eligibility criteria, they will receive a detailed information sheet and have the opportunity to ask questions. Participation only begins once the patient has signed the informed consent form. Importantly, participants can withdraw from the study at any time, without affecting their regular medical care.
Taking part in a clinical trial means following the study protocol, which may include more frequent medical visits, tests, and procedures than in standard clinical practice. Participants are expected to follow the instructions provided and communicate any concerns or questions to the research team.
Many trials use a randomized design, where participants are randomly assigned to different groups. One group may receive the investigational treatment, while the other receives a standard treatment or a placebo. In most cases, neither the participant nor the physician knows which treatment is being administered (a process known as double-blinding).
Taking part in a clinical trial means following the study protocol, which may include more frequent medical visits, tests, and procedures than in standard clinical practice. Participants are expected to follow the instructions provided and communicate any concerns or questions to the research team.
Many trials use a randomized design, where participants are randomly assigned to different groups. One group may receive the investigational treatment, while the other receives a standard treatment or a placebo. In most cases, neither the participant nor the physician knows which treatment is being administered (a process known as double-blinding).
Although investigational drugs and treatments used in clinical trials have undergone prior testing and comply with safety standards, unexpected side effects may still occur. For this reason, the research team carefully monitors all participants throughout the study.
Some potential risks or inconveniences of participating include:
Before enrolling, participants are encouraged to discuss all potential risks and benefits with the study doctor and research team. All clinical trials are covered by insurance to protect participants in the event of study-related harm.
La investigación en seres humanos está estrictamente regulada por principios científicos, éticos y legales. La Agencia Española de Medicamentos y Productos Sanitarios (AEMPS) y el Comité de Ética de la Investigación con medicamentos (CEIm) son los organismos que regulan la realización de los ensayos clínicos. Estos deben seguir las recomendaciones para ensayos clínicos y evaluación de medicamentos en humanos, según lo establecido en las Guías de Buenas Prácticas Clínicas (GCP) de la Conferencia Internacional de Armonización, la Declaración de Helsinki (en sus sucesivas revisiones por la Asamblea Médica Mundial) y la legislación vigente sobre ensayos clínicos en Europa y España.
Participation in a clinical trial should not involve any cost to the participant. While each study is different, the sponsor typically covers all costs related to the research and any specific tests required.
In some studies, volunteers may receive compensation for their participation. This is usually proportional to the duration of the study and the level of inconvenience, helping to offset travel or other related expenses. The amount varies depending on the number of visits or hospital stays required.
Once the trial is completed, all data is compiled and conclusions are drawn about the treatment’s effectiveness. If the results are favorable, they are usually submitted to health authorities for marketing approval and usage recommendations. In some cases, the results may lead to the withdrawal of a drug from the market if it proves ineffective or poses health risks. Additionally, if the participant wishes, they may request a report with the results of the research in which they took part.
The information collected about participants can only be used for the purposes of the study and will be stored in a way that does not identify the patient. Your identity will not be disclosed to anyone, except in cases of medical emergency or legal obligation. All personnel involved in the trial are required to maintain data confidentiality in accordance with applicable European and national data protection regulations.
For more information, please consult here: https://www.aemps.gob.es/medicamentos-de-uso-humano/investigacion_medicamentos/ensayosclinicos