CRA Phase I-IV Clinical Trials 2 — Questions and Answers
Question 1: In a Phase I dose-escalation study, what is the primary purpose of a 'sentinel dosing' strategy?
- To identify the maximum tolerated dose more quickly
- To administer the dose to one or two subjects first before dosing the rest of the cohort (Correct answer)
- To randomize subjects to different dose levels simultaneously
- To allow subjects to self-administer study drug under supervision
Correct answer: To administer the dose to one or two subjects first before dosing the rest of the cohort
Sentinel dosing involves treating one or two subjects before the remainder of a cohort to allow early safety monitoring before wider exposure.
Question 2: A Phase II trial is designed with a Simon two-stage design. What is the main advantage of this design?
- It eliminates the need for a control group
- It allows early termination for futility after the first stage (Correct answer)
- It guarantees statistical significance with fewer subjects
- It permits dose escalation mid-trial without protocol amendment
Correct answer: It allows early termination for futility after the first stage
The Simon two-stage design allows early stopping if the drug shows insufficient activity in stage one, conserving resources and protecting subjects.
Question 3: Which regulatory submission is typically required before initiating a Phase I clinical trial in the United States?
- New Drug Application (NDA)
- Biologics License Application (BLA)
- Investigational New Drug Application (IND) (Correct answer)
- Abbreviated New Drug Application (ANDA)
Correct answer: Investigational New Drug Application (IND)
An IND must be submitted to and allowed by the FDA before a sponsor can begin human clinical testing of an investigational drug.
Question 4: In Phase III trials, what does the term 'superiority trial' mean?
- The trial tests whether a new drug is better than placebo or active comparator (Correct answer)
- The trial tests whether a new drug is no worse than an existing treatment
- The trial is designed for a superior or premium patient population
- The trial uses a superior randomization method such as stratified block randomization
Correct answer: The trial tests whether a new drug is better than placebo or active comparator
A superiority trial is designed to demonstrate that the new treatment is statistically better than the comparator or placebo.
Question 5: During a Phase IV post-marketing study, a CRA identifies a serious unexpected adverse drug reaction in multiple subjects. What is the most appropriate immediate action?
- Wait until the study ends to include the finding in the final report
- Notify the sponsor's pharmacovigilance team immediately per protocol (Correct answer)
- Discontinue all subjects from the study without sponsor notification
- Report directly to the FDA without informing the sponsor
Correct answer: Notify the sponsor's pharmacovigilance team immediately per protocol
Serious unexpected adverse reactions must be reported to the sponsor's pharmacovigilance team immediately so expedited regulatory reporting can occur.
Question 6: What distinguishes a Phase IIb trial from a Phase IIa trial?
- Phase IIa is conducted in healthy volunteers while Phase IIb uses patients
- Phase IIa assesses proof-of-concept while Phase IIb focuses on dose-finding (Correct answer)
- Phase IIb requires a placebo group whereas Phase IIa does not
- Phase IIb is conducted internationally while Phase IIa is single-country only
Correct answer: Phase IIa assesses proof-of-concept while Phase IIb focuses on dose-finding
Phase IIa typically explores proof-of-concept and initial efficacy signals, while Phase IIb is a more rigorous dose-ranging study to select the optimal dose for Phase III.
Question 7: A sponsor wants to run a combined Phase I/II trial. Which ICH guideline is most relevant to the design of such a seamless adaptive trial?
- ICH E6(R2) — Good Clinical Practice
- ICH E9(R1) — Addendum on Estimands and Sensitivity Analysis
- ICH E8(R1) — General Considerations for Clinical Studies (Correct answer)
- ICH E11 — Clinical Investigation of Medicinal Products in the Pediatric Population
Correct answer: ICH E8(R1) — General Considerations for Clinical Studies
ICH E8(R1) provides general considerations for the design, conduct, and reporting of clinical studies including adaptive and seamless designs.
CRA Phase I-IV Clinical Trials 2
In a Phase I dose-escalation study, what is the primary purpose of a 'sentinel dosing' strategy?