The U.S. Code of Federal Regulations (CFR) specifies when sponsors must notify FDA of changes to investigational drug studies under 21 CFR 312.30. A protocol amendment is required if there is:
A change to the protocol (e.g., objectives, design, subject population, dosing, or procedures).
The addition of a new investigator.
A change in the chemistry, manufacturing, or controls (CMC) that could significantly affect product quality or safety.
Among the listed options, a change in the manufacturing site (D) directly falls under significant manufacturing changes, requiring FDA submission. Changes in investigator financial interests (B) are covered under 21 CFR 54 and reported separately, not as protocol amendments. Addition of a sub-investigator (C) does not require a formal amendment, only site-level documentation and delegation log update. Addition of a monitoring test (A) may affect the protocol, but not necessarily mandate an amendment unless it changes objectives or subject safety endpoints.
Therefore, the correct answer is D. This ensures FDA oversight of product safety, efficacy, and compliance with CMC standards before investigational use.
[References:, , 21 CFR 312.30 (Protocol amendments)., , 21 CFR 312.23(a)(7) (Chemistry, manufacturing, and controls information)., ]
