All You Need to Know about Clinical Trials

What is a clinical trial? What phases does it have and who can participate in it? In this article, Avrio Biopharmaceuticals will give answers to these questions and help you feel more confident when deciding whether to take part in one of them.

Clinical Trials

What are clinical trials?

A clinical trial is a study of new drugs, as well as new ways to prevent, detect or treat diseases using volunteer people. When a new medicine is being studied, it is usually unknown whether it will be useful, harmful, or will not differ from existing alternatives. The task of a clinical trial is to determine whether or not the drug being studied is effective, and whether the new treatment is safe.

Who conducts clinical research?

Clinical researches are funded or sponsored by various organizations. Most often, sponsors are pharmaceutical companies – drug developers, but this role can also be played by doctors, foundations, medical institutions, community groups and online pharmacies like Trusted Tablets with the official website

A researcher is a doctor or group of doctors from clinical centers where research is permitted. A research team is also involved in a clinical trial, which may include doctors, nurses, social workers, and other healthcare professionals.

Why participate in clinical trials?

People take part in clinical trials for various reasons. For some, the motive to participate in the study is the opportunity to contribute to the development of new methods of treatment and, thus, to help other people recover.

Most people with complex long-term illnesses believe that clinical research is an opportunity to receive the best treatment, giving hope for a cure when existing methods fail. Thanks to participation in clinical trials, patients receive free access to innovative drugs, modern diagnostics according to world standards, and supervision from highly qualified specialists and additional medical care.

Who can participate in clinical trials?

Clinical trials are conducted according to a plan known as a protocol. Each clinical trial has specific requirements for who can participate, and all of them are listed in the protocol.

One of the reasons that you are not allowed to participate in a clinical trial may be the inconsistency of the set of criteria by which participants in clinical trials are selected.

The factors that allow someone to participate in a clinical trial are called “inclusion criteria.” Those who exclude from the participants or do not allow their participation are called “exclusion criteria”. These criteria are based on such factors as age, gender, type of disease, its stage, previous history of treatment and other diseases.

Phases of clinical trials

First, preclinical studies are conducted in laboratories in which drugs are tested on cages and animals. Then, the most promising experimental drugs are allowed at further stages of a clinical trial.

  • Phase I. The first experience of using an experimental drug in humans. A clinical trial in this phase usually includes a small number of participants – from 20 to 80. The main goal of Phase I is to find the highest dose of a new drug that can be applied safely without severe negative reactions. First participants usually receive a low dose of the drug and are under close observation. If there is only a slight toxicity after taking the drug, the next few participants may receive a higher dose. This process goes on until the doctors find the dose effective and having a satisfactory level of toxicity. Due to the small number of participants in Phase I trials, rare adverse effects may not be identified. In general, participation in this phase has the greatest potential risk;
  • Phase II. If the new drug is safe enough in phase I, then Phase II is initiated to find out if it is working. To test the drug, 100-300 participants are required. The goal is to investigate the effectiveness of the drug in a particular disease, study the pharmacokinetics of the drug. Also, the drug safety check continues. As a rule, all participants receive the drug in the same dose prescribed during phase I;
  • Phase III. If a new drug or method will prove to be effective for a sufficient number of participants, and the adverse reactions are not so serious, the drug proceeds to phase III. In this phase, the drug is tested on a large number of participants, at least 300-500, in order to show its effectiveness with a specific disease in a representative group of patients, as well as to reveal rare side effects and compare the safety and efficacy of the new treatment with the standard one. Since doctors still do not know which treatment is better, research participants are often chosen in a random order. When this is possible, neither the participant nor the healthcare professional knows which of the drugs the patient receives. This type of study is called a double-blind study. Phase III is conducted, as a rule, in the form of international multicenter studies, in which patients from different countries participate. The data obtained in Phase III is the basis for creating instructions for the use of the drug. If the drug is successfully tested in the first three phases, it receives a registration certificate;
  • Phase IV is carried out after the start of the sale of the drug. In this phase, clinical trials are performed to identify and evaluate the long-term effects of using a new drug for a large number of patients, for example, how it interacts with other medicinal substances. Information obtained in Phase IV may contribute to the fact that the drug will be excluded from the market or restrictions will be imposed on its use. This is the safest phase because the drug is already well studied and used by thousands of people.

Are patients paid for participation in the trial?

Usually, only participation in phase I studies is paid when the drug is tested on healthy volunteers. At other stages, the financial incentive is excluded, so that the decision on participation is truly voluntary and independent. Some studies may cover the cost of parking, transportation and food. If the participant receives any payment or compensation for participation in the clinical trial, then this will necessarily be stated in informed consent.

Where to find a clinical trial?

There is only one resource, used to search for clinical trials conducted in the United States – – the international registry of clinical studies of the US National Institutes of Health. This resource is useful for more detailed and important research information.

Category: Healthcare

Tags: clinical trials, drug production, health professions, quality drugs