CPI Treatment Planning & Protocols 3 — Questions and Answers
Question 1: In a clinical trial protocol, an 'allowed concomitant medication' list is provided. A subject requires a drug NOT on the list. The investigator should:
- Prescribe the medication and document it as standard of care
- Withhold the medication until the subject completes the trial
- Consult the protocol's prohibited medication section, contact the sponsor, and document the decision (Correct answer)
- Automatically discontinue the subject from the trial
Correct answer: Consult the protocol's prohibited medication section, contact the sponsor, and document the decision
When a concomitant medication is not addressed, the investigator must cross-reference prohibited lists, consult the sponsor, and carefully document the clinical rationale.
Question 2: A protocol specifies 'stratified randomization' by disease severity. What is the PRIMARY advantage of this approach over simple randomization?
- It speeds up the enrollment process significantly
- It ensures balance of key prognostic factors across treatment arms (Correct answer)
- It eliminates the need for a placebo control group
- It allows investigators to select which treatment subjects receive
Correct answer: It ensures balance of key prognostic factors across treatment arms
Stratified randomization ensures that important prognostic variables are balanced between arms, reducing confounding.
Question 3: A physician investigator receives a protocol that includes a 'run-in period' before randomization. What is the primary purpose of a run-in period?
- To allow the sponsor to review preliminary data before committing to full enrollment
- To assess subject compliance, tolerability, or to wash out prior treatments before randomization (Correct answer)
- To permit investigators to select the most favorable subjects for randomization
- To satisfy FDA requirements for pre-randomization data collection
Correct answer: To assess subject compliance, tolerability, or to wash out prior treatments before randomization
Run-in periods assess compliance, tolerability to study drug, or eliminate prior treatment effects before subjects are randomized.
Question 4: Under ICH E6(R2) GCP guidelines, the protocol must include which of the following regarding treatment?
- Marketing strategy for the investigational product post-trial
- Description of investigational product, dose, schedule, route, and duration (Correct answer)
- Investigator's personal clinical experience with similar treatments
- Insurance coverage terms for study-related injuries
Correct answer: Description of investigational product, dose, schedule, route, and duration
ICH E6(R2) requires the protocol to specify the investigational product's dose, dosage regimen, route of administration, and treatment duration.
Question 5: A subject in a double-blind trial develops symptoms suggesting the study drug rather than placebo. The investigator considers unblinding. In what circumstance is emergency unblinding justified?
- When the investigator is curious about the subject's treatment assignment
- When knowledge of treatment assignment is essential for subject safety or medical management (Correct answer)
- When the subject requests to know their treatment assignment
- When the IRB requests interim efficacy data
Correct answer: When knowledge of treatment assignment is essential for subject safety or medical management
Emergency unblinding is justified only when knowing the treatment assignment is medically necessary for subject safety.
Question 6: A Phase III protocol uses a 'non-inferiority' design. What does this mean for the treatment planning hypothesis?
- The experimental treatment is expected to be dramatically superior to standard therapy
- The experimental treatment is hypothesized to be no worse than the active comparator by a pre-specified margin (Correct answer)
- The study will demonstrate that no treatment is necessary for the condition
- Both treatments are expected to produce identical outcomes
Correct answer: The experimental treatment is hypothesized to be no worse than the active comparator by a pre-specified margin
Non-inferiority trials test whether an experimental treatment is not worse than an active comparator by a clinically acceptable margin (the non-inferiority margin).
Question 7: When a protocol includes an 'interim analysis,' what is the primary risk that must be managed?
- Increased cost of the trial due to additional statistical testing
- Inflation of Type I error (false positive) if proper alpha spending is not applied (Correct answer)
- Delayed enrollment due to data lock requirements
- Loss of subject confidentiality during data review
Correct answer: Inflation of Type I error (false positive) if proper alpha spending is not applied
Interim analyses increase the chance of a false positive finding unless an alpha spending function (e.g., O'Brien-Fleming) is pre-specified to control Type I error.
CPI Treatment Planning & Protocols 3
In a clinical trial protocol, an 'allowed concomitant medication' list is provided.
A subject requires a drug NOT on the list.
The investigator should: