Clinical Trials

Question 1

What are clinical trials?

Answer 1

Interventional studies where researchers test new treatments, drugs, or medical devices under controlled conditions.

Question 2

What is the purpose of Phase 1 in clinical trials?

Answer 2

Determine safe dosage, side effects, and how the drug is processed in the body.

Question 3

How many participants are typically involved in Phase 1 of clinical trials?

Answer 3

Small group (20–80 healthy volunteers or patients).

Question 4

What is the main focus of Phase 2 in clinical trials?

Answer 4

Assess effectiveness and further evaluate safety.

Question 5

What is the participant group size for Phase 2 clinical trials?

Answer 5

Larger group (100–200 patients with the disease).

Question 6

What occurs during Phase 3 of clinical trials?

Answer 6

Compare the new treatment with existing treatments or placebo.

Question 7

What is the typical participant size for Phase 3 clinical trials?

Answer 7

Large population (1,000–3,000+ patients).

Question 8

What happens if a drug is successful in Phase 3?

Answer 8

It may receive regulatory approval (e.g., FDA, EMA).

Question 9

What is the purpose of Phase 4 in clinical trials?

Answer 9

Detect rare side effects and evaluate long-term safety & effectiveness.

Question 10

Who are the participants in Phase 4 clinical trials?

Answer 10

General population (long-term monitoring).

Question 11

What is a key aspect of the regulatory review process in Phase 3?

Answer 11

Ensure the possibility of bias is minimized.

Question 12

What does ‘Controlled’ mean in methodological features?

Answer 12

The treatment is evaluated against a defined alternative.

It serves as a baseline for comparison and allows clear interpretation of results.

Question 13

What is the purpose of a Control group?

Answer 13

Receives (as close as possible) the same treatment as the intervention group except for the intervention being assessed.

Question 14

What does ‘Randomized’ refer to in research methodology?

Answer 14

Patients are allocated to treatments at random, ensuring comparability.

Question 15

What is the purpose of blinding in studies?

Answer 15

To reduce bias.

Question 16

What are the types of blinding?

Answer 16

• Single (either subject or assessor is blind)
• Double (both subjects or assessors blind)
• Triple (data analyst is also blind)

Question 17

What are Open Label Trials?

Answer 17

Participants are aware which treatment they have been allocated to.

Question 18

What is the purpose of Open Label Trials?

Answer 18

Used to compare treatments and gather additional information about the long-term effects in intended patient populations.

Question 19

What is Intention-to-treat analysis?

Answer 19

Analysis based on treatment allocation, not adjusted for compliance.

Question 20

How are participants counted in Intention-to-treat analysis?

Answer 20

All persons randomized to a treatment are counted in the analysis.

Question 21

What does ‘per protocol’ analysis refer to?

Answer 21

Analyzing those who complete treatment.

Question 22

When is Intention-to-treat analysis particularly useful?

Answer 22

If treatments are long, e.g., TB drugs.

Question 23

What percentage of new therapeutic products that reach clinical testing are not approved or reach commercialization?

Answer 23

90%

This statistic highlights the high failure rate in the clinical trial process.

Question 24

What percentage of clinical trial failures are due to lack of efficacy?

Answer 24

52%

This indicates that more than half of the failures are because the treatment does not work as intended.

Question 25

What are the two main reasons for clinical trial failures?

Answer 25

* Lack of efficacy (52%) * Safety issues (24%) ## Footnote Safety issues refer to adverse drug reactions that can occur during trials.

Question 26

What percentage of clinical trial failures is attributed to safety issues?

Answer 26

24% ## Footnote This figure represents the failures due to adverse drug reactions.

Question 27

What percentage of clinical trial failures occur due to various technical or commercial reasons?

Answer 27

24% ## Footnote These reasons can include issues like manufacturing problems or market conditions.

Question 28

What was thalidomide initially marketed as in the 1950s?

Answer 28

A sedative

Question 29

For what condition was thalidomide later promoted to treat?

Answer 29

Morning sickness in pregnant women

Question 30

What was a significant flaw in the preclinical testing of thalidomide?

Answer 30

It was tested on rodents, which do not metabolize drugs like humans

Question 31

What type of clinical trials were not performed before thalidomide's distribution?

Answer 31

Proper randomized controlled trials (RCTs)

Question 32

What long-term studies were lacking in thalidomide's testing?

Answer 32

Long-term safety studies in humans

Question 33

How were patients monitored for side effects during thalidomide trials?

Answer 33

Patients were not properly monitored

Question 34

What severe issue was noticed by doctors in the late 1950s related to thalidomide?

Answer 34

An increase in severe limb deformities in newborns

Question 35

How long did it take to identify thalidomide as the cause of birth defects?

Answer 35

Several years

Question 36

Approximately how many babies worldwide were affected by thalidomide-related birth defects?

Answer 36

10,000+ babies

Question 37

What other tragic outcomes were associated with thalidomide use besides birth defects?

Answer 37

Many stillbirths and miscarriages

Question 38

What do observational studies involve?

Answer 38

Monitoring participants in real-world settings to identify patterns, risk factors, and treatment outcomes ## Footnote Observational studies do not involve active interventions.

Question 39

Are participants in observational studies assigned to specific interventions?

Answer 39

No, participants are not assigned to specific interventions by the investigator ## Footnote Participants may receive interventions as part of their routine medical care.

Question 40

What is a Cohort Study?

Answer 40

A study that follows a group of people over time to assess risk factors and disease development ## Footnote Example: Studying smoking habits and lung cancer incidence.

Question 41

Fill in the blank: In observational studies, participants may receive _______ as part of their routine medical care.

Answer 41

[interventions]

Question 42

True or False: Observational studies involve active interventions.

Answer 42

False

Question 43

What can interventions in observational studies include?

Answer 43

Medical products, such as drugs or devices, or procedures ## Footnote Interventions are part of routine medical care but not assigned by the investigator.