What is a clinical study?
Clinical studies are a type of research studies aimed to:
- identify or verify the clinical, pharmacological, or other pharmacodynamic actions of a drug
- identify probable side effects of the drug
- study the absorption, distribution, metabolism, and excretion of the under-investigation drug, and to determine its efficacy and safety
- compare the clinical efficacy of the new drug to existing therapies for a specific disease
How is a new drug studied and evaluated?
The development of a new drug occurs in two stages:
- Stage of preclinical studies
- Stage of clinical studies
In the first stage, wide doses are tested using in vitro (test tube or cell culture) and in vivo (animal) experiments, to evaluate the efficacy and safety of the new drug. In most cases test animals are usually rats or rabbits which have similar drug metabolism to human. The duration of preclinical studies is usually 3 to 4 years.
The clinical studies are classified in four phases:
- trials. The new drug is tested on a small group of healthy volunteers (usually 20-80 subjects). These trials are designed to evaluate the safety and tolerability of a drug in different doses. Side effects are also recorded.
- Phase II trials. Larger group of patients (100-300 subjects) suffering from a specific disease are treated with the under-investigation drug, to estimate the efficacy and to continue the Phase I safety assessments.
- Phase IIΙ trials. The efficacy and safety of the new drug is investigated in a large patient population (1.000-3.000 subjects) over a period of 6 to 12 months or longer. The goals are the comparison to placebo or preexisting therapies, the monitoring of adverse effects and the collection of all the necessary information for the optimum use of the new drug.
- Phase IV trials. After approval, thousands of patients receive the new drug, to assess its effectiveness, cost-effectiveness, and safety in real-world settings. The safety surveillance is designed to detect any rare or long-term adverse effects over a much larger patient population and longer period.
Who can participate in a clinical study?
The candidates may be of any age group and may be healthy volunteers or patients. In each study the researchers identify factors called inclusion criteria that allow one to participate in the study, and factors called exclusion criteria which disqualify the participation.
Who sponsors clinical studies?
Clinical research can be sponsored by the state, pharmaceutical companies, or non-profit organizations.
What way do clinical studies work?
- The researchers prepare the protocol of the clinical study, to give the appropriate answers to specific questions.
- The protocol is checked by the National Organization for Medicines and the National Commission of Ethics, which examine the adequacy of the design, the potential hazards to the participants and bioethics problems. The study can start only after the approval required.
- Most clinical studies include two groups, the active treatment, and the control group. In the first group, the participants take the under-investigation drug, while in the control group they receive a placebo or an already approved drug for a specific disease. The participants are classified randomly in the two groups.
What is placebo?
Placebo is a product that looks and tastes like the active treatment being tested but contains no medication. Comparing results deriving from the two groups shows researchers whether changes in the active treatment group were related to taking the treatment, or if they occurred by chance or other factors.
What is inform consent?
To take part in a clinical study, the participant must sign an informed consent document to show that one was given information on the risks, potential benefits, and alternatives and that he understands it. Signing the document and providing consent is not a contract. Participants may withdraw from a study at any time, even if the study is not over.
Do I have any responsibilities during my participation in a clinical study?
All participants have the following responsibilities:
- Confirm that the contact details you have provided are correct
- Provide accurate information regarding your personal and family medical history
- Apply the instructions provided by the scientific personnel
- Accuracy in all planned meetings
- Immediate briefing of the research personnel about any adverse events experienced while participating in the study
Do I have any rights as a participant?
All participants in a clinical study, have the following rights:
- To be treated with respect and sincerity
- To be aware of the aim of the study
- To be aware of the name and the contact details of the principal investigator
- To have the opportunity to submit any question you wish to the scientific staff and get the decision to participate in the study without feeling any psychological pressure
- To be able to ask for additional information in any phase of the study
- To withdraw from the study without any consequences
- To be aware of who may have access to your personal medical file
How can I register in a clinical study?
In the web page of the Special Unit for Biomedical Research and Education you can find and complete an application, which will be checked by the research personnel of the clinical study and you will receive an answer as soon as possible.