CRA Phase I-IV Clinical Trials 3 — Questions and Answers
Question 1: In a first-in-human Phase I oncology trial using the 3+3 dose escalation design, the first cohort of 3 patients shows 1 dose-limiting toxicity (DLT). What happens next?
- Escalate to the next dose level immediately
- Stop the trial and declare the dose unsafe
- Enroll 3 additional patients at the same dose level (Correct answer)
- De-escalate to a lower dose level for the next cohort
Correct answer: Enroll 3 additional patients at the same dose level
In the 3+3 design, one DLT in three patients triggers enrollment of three additional patients at the same dose before deciding on escalation or de-escalation.
Question 2: What is the primary objective of a pharmacokinetic (PK) study conducted as part of a Phase I trial?
- To evaluate the drug's efficacy in a disease population
- To characterize absorption, distribution, metabolism, and excretion of the drug (Correct answer)
- To confirm the drug's mechanism of action at the receptor level
- To determine long-term safety over multiple years
Correct answer: To characterize absorption, distribution, metabolism, and excretion of the drug
Phase I PK studies characterize the ADME profile to understand how the body processes the drug and to inform dosing regimens.
Question 3: A Phase III randomized controlled trial uses a double-blind design. Who in the trial is kept unaware of treatment assignment?
- Only the subjects
- Only the investigators
- Both the subjects and the investigators (Correct answer)
- Only the sponsor's biostatisticians
Correct answer: Both the subjects and the investigators
In a double-blind design, both subjects and investigators are unaware of treatment assignment to minimize bias in outcome assessment and reporting.
Question 4: Which of the following best describes an 'adaptive seamless Phase II/III design'?
- A trial that combines Phase II and Phase III patient data in a single analysis (Correct answer)
- A trial with no interim analyses and a single final endpoint analysis
- A trial where Phase II and Phase III are run sequentially with separate statistical plans
- A trial design that eliminates the need for FDA pre-approval
Correct answer: A trial that combines Phase II and Phase III patient data in a single analysis
An adaptive seamless Phase II/III design combines both phases into a single trial, and data from both stages may contribute to the final confirmatory analysis.
Question 5: In the context of Phase IV commitments, what is a 'required post-marketing study' (RPMS)?
- An optional observational registry voluntarily submitted by sponsors
- A study the FDA requires as a condition of drug approval (Correct answer)
- A pharmacoeconomic analysis submitted five years after launch
- A study initiated by academic researchers independent of the sponsor
Correct answer: A study the FDA requires as a condition of drug approval
An RPMS is mandated by the FDA as a condition of approval, typically to evaluate a safety concern not fully characterized during pre-approval studies.
Question 6: A CRA is monitoring a Phase II oncology trial and notices the site has missed collecting mandatory tumor biopsy samples from three subjects. What should the CRA do first?
- Immediately terminate the subjects' participation in the trial
- Document the deviation and discuss with the site to understand the root cause (Correct answer)
- Notify the IRB before contacting the sponsor
- Unblind the data to assess if the missed samples affect efficacy outcomes
Correct answer: Document the deviation and discuss with the site to understand the root cause
The CRA should document the protocol deviation and work with the site to identify the root cause before escalating, following sponsor SOPs.
Question 7: What term describes the dose level just below the dose that causes unacceptable toxicity in at least 2 of 6 subjects in a 3+3 Phase I design?
- Minimum effective dose (MED)
- Recommended Phase 2 dose (RP2D)
- Maximum tolerated dose (MTD) (Correct answer)
- No-observed-adverse-effect level (NOAEL)
Correct answer: Maximum tolerated dose (MTD)
The MTD is defined as the dose level just below the dose where 2 or more of 6 patients experience a DLT in the 3+3 design.
CRA Phase I-IV Clinical Trials 3
In a first-in-human Phase I oncology trial using the 3+3 dose escalation design, the first cohort of 3 patients shows 1 dose-limiting toxicity (DLT).
What happens next?