The Course of Clinical Studies

The course of a clinical trial can be described both from the perspective of the drug and the patient.

When we talk about clinical studies as the process from the invention of a new molecule to its approval for use, there are usually "clinical study phases". On the other hand, a patient can take part in a specific phase of a clinical study, and his path in the study will be divided into certain characteristic stages. More about the details of the phases and stages of studies can be found below.
Phases of drug clinical studies

Phases of drug clinical studies

Clinical studies are divided into phases - each of them must end with a positive result so that the next one can begin.

Phase 1

First, the safety of the test substance is initially assessed. In a group of several dozen healthy volunteers, its metabolism, absorption, excretion, possible toxicity, and interactions with other drugs are being investigated.

Phase 2

At this stage of the study, it is determined whether the drug works in a specific group of patients and whether it is safe for them. The relationship between the dose and the effect of the new drug is also assessed.

Phase 3

It is aimed at final confirmation of the effectiveness of the test substance in the treatment of a given disease. This stage includes the investigation of the relationship between the safety of the drug and its effectiveness during short-term and long-term use.

Phase 4

The last phase of a clinical study concerns drugs that are registered and marketed, i.e. available for sale. This stage is aimed at determining whether the drug is safe in all indications recommended by the manufacturer and for all groups of patients. In this phase, the results obtained in the previous phases are additionally verified. As part of Phase 4, new indications for an already registered drug are also being tested.

Phases of a clinical study from the patient’s perspective

Participation in a clinical study from the patient's perspective consists of several stages.

The first, beginning with the signing of the Informed Consent Form, is called the "screening period" or "screening" - during this time, the patient's medical records are reviewed, laboratory, imaging, and/or endoscopic tests are carried out, and data on disease activity are collected. All these activities are aimed at confirming that the patient meets the criteria for participation in the study.

After the screening period and qualifying for therapy, the patient is transferred to the treatment period. Depending on the study, the duration of treatment may vary - some studies assume only a few weeks of drug administration, while other studies may be designed to last several years.

During the study, the patient remains under the constant care of his treating physician and may contact him at any time, especially in the event of any health ailments that raise concerns or medical problems that require resolution by the physician. It is also always possible to contact the study coordinator, who provides assistance in organizational matters, sets the dates of visits, and is the second contact person if the treating physician remains out of reach.

During the study, the patient's health is constantly monitored - both the diary of disease symptoms and regular medical visits, blood collection during visits, control of vital signs, and repeated periodic ECG, audiometry, or endoscopic examinations are used for this purpose.

Adverse events may occur during the study. Since patient safety is an absolute priority, patients are always asked to inform the staff immediately about this fact. The patient is asked for information regarding the duration of the event and possible additional treatment.

An adverse event is any medical fact about a patient that deviates from the normal state. It may be reported by the patient and considered adverse or result from changes in the results of diagnostic tests, which should not occur according to the physician’s opinion. All deviations are recorded, even if the lack of connection with the experimental treatment seems obvious.

After the treatment period, the patient goes to the observational (safety) stage; its duration varies from 4 weeks to 16 weeks, and sometimes up to 30. This is the time after the end of taking the drug in which the patient is still a participant in the study, but the visits are limited to 1 or 2 meetings, during which a doctor's visit and possible collection of samples for laboratory tests take place. This period is to check the patient's well-being and safety after discontinuation of the drug.

After completing all stages of participation in a clinical trial, the patient may remain under the care of their physician and start any new treatment of the underlying disease. Previous participation in a clinical study does not preclude participation in another trial with a different drug or treatment under a drug program financed by the National Health Fund.

Phases of a clinical study from the patient’s perspective