Classes #16-#19: Interventional Study Designs

Question 1

What type of study is required by the FDA in order to get consideration for approval of a new drug?

Answer 1

Interventional Study

Question 2

What are some other common names for interventional study designs?

Answer 2

Clinical Trial
Clinical Study
Experimental Study
Human Study
Investigational Study

*NOT the only design for these terms for studies

Question 3

When comparing observational studies and interventional study design, what are the key differences of interventional studies?

Answer 3

> Investigator selects “interventions” and allocates study subjects to forced-intervention groups

> More “rigorous” in ability to show cause-and-effect
- can demonstrate CAUSATION

Question 4

What are the phases of interventional studies?

Answer 4

Pre-Clinical -> Phase 1 -> Phase 2 -> Phase 3 -> Phase 4

Question 5

Bench and Animal research would be in which phase of interventional studies?

Answer 5

Pre-Clinical (prior-to human investigation

Question 6

What is the primary focus of the researchers in phases 1 and 4 in an interventional study?

Answer 6

Safety

*remember that safety is always of concern

Question 7

Which phase of an interventional study would most likely be expected if the study was of short duration and had an N-value of 79?

Answer 7

Phase 1 (new drug/device/procedure)

Question 8

What is the primary focus of phases 2 and 3 in an interventional study design?

Answer 8

Primary focus is on effectiveness (efficacy).

Question 9

In a study that reaches phase 4 that is looking at a new drug, what change would you expect about the drug between phase 3 and 4?

Answer 9

The drug would not reach phase 4 without having a name. Thus, a named drug.

Question 10

What is the average N-value in a phase 2 study and what is the expected duration of the study? Also, is restriction present in participants allowed to enter the study?

Answer 10

N-value = 100-300 people

Short-to-Medium Duration (a few to several months)

Yes, likely to have a narrower inclusion criteria for participants in study

Question 11

What kind of patients are usually chosen for phase 2 studies?

Answer 11

Commonly utilize patients with condition of interest, used to expand on purpose of Phase 1 study (safety) but also to begin assessing efficacy in diseased population.

Question 12

For a phase 3 study, what is the expected N-value, study duration, and typical patient selection criteria?

Answer 12

N (1,000-3,000)

Long duration (many months to a year (or few years))

Used in patients with condition of interest to continue determination of safety, with primary purpose to assess efficacy.

Question 13

In which phase of interventional study design does the FDA approve or not prove a drug of interest?

Answer 13

Phase 3

Question 14

Can a drug that’s in phase 3 of an interventional study be named?

Answer 14

Yes

*Dr. Segars said, “don’t get confused on the exam if I give you a study that has a named drug and think that it can’t be phase 3 and that it is only in phase 4”.

Question 15

Would an interventional study enter phase 4 after or before approval from the FDA?

Answer 15

After approval from the FDA.

*phase 4 (post-marketing)

Question 16

Discus phase 4 of a study and why it is performed and sometimes mandated by the FDA?

Answer 16

Long-term effects (risks and benefits) in a large population of diseases patients (expanded use population (age, ethnic)).
- registries, survey’s (e.g., FDA’s MedWatch/FAERS/VAERS programs)

Question 17

What are 2 advantages of an interventional trial, versus other designs?

Answer 17

1) Cause precedes effect (shows Causation)

2) Only design used by FDA for “approval” process (on-label)

Question 18

What are a few of the disadvantages of interventional trials, versus other designs?

Answer 18

1. cost
2. complexity/time (development/approval/conductance)
3. ethical considerations (risk vs. benefit evaluation)
4. generalizability (a.k.a.; External Validity) - is study population similar to general population and will methodology and findings be applicable to them?

Question 19

What is the only type of study that can prove causation?

Answer 19

Interventional Study