When can an investigator deviate from the protocol?

• A. Never.
• B. Only where necessary to eliminate immediate hazards to trial participants.
• C. When the sponsor approves.
• D. At any time for operational reasons.

Answer: (B)

The key idea is that participant safety drives any departure from the study plan. An investigator may deviate from the protocol only to eliminate an immediate hazard to trial participants. This allows a rapid, safety-driven action without waiting for formal approvals, but it must be documented and communicated to the sponsor and the ethics committee as soon as feasible, and a formal protocol amendment should be pursued afterward if the change is to be kept.

This is why the correct approach is to act only when immediate safety concerns require it. Deviation for convenience or operational reasons isn’t permitted, and it isn’t acceptable to rely on sponsor approval alone to justify a change that could affect safety or data integrity. If a deviation occurs, it should be clearly explained in records, and the sponsor/IRB should be informed so appropriate oversight and potential amendment can follow.