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Classification of Clinical Trials

• 01

  Phase 1 clinical trial

  The phase 1 clinical trial is a clinical trial that aims to determine the pharmacokinetics, pharmacological action in the human body, side effects, and the safe dose (tolerance) of a drug after administering the drug to a relatively small number of healthy people (usually between 20 and 80 subjects, sometimes less than 20) based on toxicity, absorption, metabolism, excretion, and pharmacological action data obtained from preclinical animal testing of drug candidates.

• 02

  Phase 2 clinical trial

  Phase 2 is a step to prove the efficacy and safety of a new drug. It is a test to confirm the pharmacological effect and determine the appropriate dosage or usage. It is usually carried out using a limited number of patients who can be carefully examined. The number of target patients is generally between 100 and 200. However, it may be performed in a much larger number of patients for drugs with a range of applicable diseases, such as antimicrobic drugs.

• 03

  Phase 3 clinical trial

  Phase 3 is conducted after the effectiveness of the new drug has been identified to some extent. It is the last clinical trial to obtain drug approval. It is a test to compare and evaluate the dose, effect, efficacy, and safety of the drug by setting a control group and a treatment group at the same time. The number of target patients depends on the characteristics of the drug. Generally, it is desirable to set the number of target patients to confirm side effects that appear with a probability of 1/1000.

• 04

  Phase 4 clinical trial

  This is a test to evaluate the long-term efficacy and safety of new drugs after it is sold and used. It may include post-marketing surveillance to obtain additional information on the frequency of side effects of new drugs, studies to search for special pharmacological effects, large-scale follow-up studies to review the effects of drug use on morbidity or mortality, clinical trials on special patient groups that were not reviewed in pre-marketing clinical trials, and post-marketing clinical studies to explore new indications.

Explanation of terms related to clinical trials

• 

  01. Clinical Trial/Study

  It refers to tests or studies conducted on humans to confirm the pharmacokinetics, pharmacodynamics, pharmacology, and clinical effects of drugs and investigate adverse reactions for the purpose of proving the safety and efficacy of investigational drugs.

• 

  02. Protocol

  It is a document describing the goals, materials and methods, statistical aspects, related organizations, etc. of a clinical trial to provide the background or basis for the clinical trial.

• 

  03. Clinical Trial/Study

  It refers to a procedure that prevents people or departments involved in a clinical trial from knowing about the assigned treatment. Single-blind generally means to blind the subject, while double-blind is blinding the subject, the examiner, the monitor, and, if necessary, the person involved in the data analysis.

• 

  04. Multicenter Trial

  It refers to clinical trials conducted in two or more test institutions according to one clinical trial protocol.

• 

  05. Serious AE/ADR

  Cases falling under any of the following items among adverse reactions or adverse drug reactions that occurred at any dose of a drug used in clinical trials

• 

  06. Adverse Drug Reaction (ADR)

  All adverse and unintended reactions that occurred at any dose of the investigational product. It is not possible to exclude a causal relationship with the investigational product.

• 

  07. Unexpected Adverse
  Drug Reaction

  When it shows differences in the pattern of adverse drug reactions or the degree of harm in light of available drug-related information (e.g., clinical investigator package or attachment of drug products)

• 

  08. Vulnerable Subject

  Subjects whose voluntary participation decisions may be affected due to expectations of benefits associated with participation in clinical trials or concerns about disadvantages they may receive from superiors in the organizational hierarchy if they refuse to participate (e.g., students of medical school, pharmacy school, dental school, nursing school, hospital or research institute employees, pharmaceutical company employees, military personnel, and prisoners), people with incurable diseases, people confined in group facilities stipulated by the Enforcement Regulations, the unemployed, the poor, patients in emergency situations, racial minorities, vagrants, refugees, minors, and subjects unable to give consent of their own free will.

• 

  09. Institutional Review
  Board

  A standing committee established independently within the trial institution to protect the rights, safety, and welfare of subjects participating in clinical trials by reviewing and continuously checking the protocol or changed protocol, and methods or provided information to obtain written consent from subjects.

• 

  10. Impartial Witness

  A person who is unrelated to the clinical trial and who can not be unfairly influenced by those involved in the clinical trial. If the subject or the subject's legal representative is illiterate, a person who will be present during the written consent process and will read the written consent form and all written information provided to the subject on behalf of the subject.

• 

  11. Clinical Trial Pharmacist

  A pharmacist who is designated by the head of the testing institution and responsible for the receipt, storage, dispensing, managing, and return of investigational drugs at the test institution.

Reference: Safe Drug World, the Ministry of Food and Drug Safety

Participation and Recruitment Procedures of Clinical Trials

• 

  NO.1Announcement of applicant recruitment

  • If applicants to participate in a clinical trial are needed, the researcher shall post a recruitment announcement or advertisement after receiving approval from the Institutional Review Board (IRB) for the consent statement and recruitment announcement.
  • Recruitment announcement or advertisement shall use the recruitment notice section on the website of the clinical trial center, the website of hospitals or related institutions, and/or if necessary, mass media (newspapers or broadcasting).

• 

  NO.2Application for participation in clinical trials

  • Although there are slight differences between the centers or institutions that host clinical trials, they generally accept applications in the following way.

    - Online application: Fill out the application form on the website of a clinical trial center (or related institution) - In-person application: Fill out the application form at related institutions and clinical trial centers - Phone (or fax) application: Call the relevant department of a clinical trial center and provide simple information orally

  • Even if an applicant cannot participate because there was no suitable trial at the time of application, the applicant may be contacted individually if the participant wishes to participate later.

• 

  NO.3Individual notification to applicants according to the test schedule

  • Notify each applicable person by e-mail or phone and arrange a visit.

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  NO.4Explanation and Preparation of Written Consent Forms

  • Applicants who are eligible to participate shall visit the clinical trial center at the scheduled visit time, obtain a sufficient explanation of the study from an authoritative person, such as an investigator or research nurse, and provide written consent by filling out a consent form.
  • When a research applicant gives written consent, the applicant must be aware of:

    - Objectives and method of the clinical trial - Expected efficacy and effects - Side effects and risks - If the applicant is a patient, whether there are other treatment methods for the current disease. - Confirmation that the applicant will not be penalized for not agreeing to participate. - Possibility of withdrawal at any time by free will after the subject has given consent to participate in the trial - Confirmation that the applicant can receive compensation and treatment in case of damage - Guaranteed confidentiality of the identity - Other human rights protection requirements, etc.

• 

  NO.5Physical examination (Screening test)

  • Only those who signed the written consent will undergo a physical examination.
  • The screening test is a process to check whether the applicant is suitable for the clinical trial.
  • The items of the screening test vary depending on the study, and it takes about 30 minutes. The results of the screening test can be obtained by contacting the relevant institution or clinical trial center.
  • The applicant will receive diverse tests including blood/urine tests, body measurements, blood pressure, and pulse as well as a medical examination by interview by a doctor in charge. Depending on the study, more complex tests may be required.
  • Precautions for accurate examination

    - No food or drink other than drinking water should be consumed for 10 hours prior to the screening test, - Please avoid excessive exercise or drinking from three days prior to the screening test.

  • The applicant may need to visit again for a retest depending on the test results.

• 

  NO.6Selection of suitable subjects and individual notification

  • Only those who are suitable according to the results of the physical examination will participate in the clinical trial.
  • Results are individually notified after 2 to 4 days (1 week for special tests).

• 

  NO.7Participation in the main clinical trial

  • Subjects who are suitable according to the results of the screening test will participate in the study according to the research plan established by the center.
  • Since the clinical trial is conducted according to the study plan as described in the explanation, the subject shall take the clinical trial drug (new drug or control drug) exactly as the researcher directs.
  • The trial drug or control drug will be administered once or repeatedly. The subject may receive clinical tests (blood and urine tests) similar to the screening test to confirm safety.
  • Blood and urine tests may be performed multiple times to evaluate pharmacokinetics and efficacy. The total amount of blood collected during the period will not exceed the amount of one blood donation.
  • Sometimes, hospitalization may be required.

• 

  NO.8End of clinical trial participation

  • If there is no specific finding during the clinical trial process, participation in the trial ends after the planned period.
  • If an unusual or severe adverse reaction occurs during the trial, participation in the test may be discontinued based on the judgment of the researcher or the will of the subject.
  • If participation terminates due to a side effect caused by the clinical trial, appropriate compensation will be made by the sponsor.

Reference: Safe Drug World, the Ministry of Food and Drug Safety