21 CFR 58.120
Protocol
21 CFR 58.120 is the regulation titled “Protocol” in 21 CFR Part 58, Good Laboratory Practice for Nonclinical Laboratory Studies. Since 2021, 1 FDA warning letter has cited it.
- Letters citing it
- 1 since 2021
- Jan 1 to Oct 30, 2026
- 0 against 0 on the same dates in 2025
- Most often cited with
- 21 CFR 58.130, in 1 letter
- Closed out
- 100% of these letters have a published close-out
Letters citing it, by year issued
It is a biologics letter. 2026 runs to Oct 30, 2026. Pick a year to see its letters.
- 02021
- 12022
- 02023
- 02024
- 02025
- 02026
The regulation
Read the text of 21 CFR 58.120 (eCFR, as of Sep 1, 2026)
(a) Each study shall have an approved written protocol that clearly indicates the objectives and all methods for the conduct of the study. The protocol shall contain, as applicable, the following information:
(1) A descriptive title and statement of the purpose of the study.
(2) Identification of the test and control articles by name, chemical abstract number, or code number.
(3) The name of the sponsor and the name and address of the testing facility at which the study is being conducted.
(4) The number, body weight range, sex, source of supply, species, strain, substrain, and age of the test system.
(5) The procedure for identification of the test system.
(6) A description of the experimental design, including the methods for the control of bias.
(7) A description and/or identification of the diet used in the study as well as solvents, emulsifiers, and/or other materials used to solubilize or suspend the test or control articles before mixing with the carrier. The description shall include specifications for acceptable levels of contaminants that are reasonably expected to be present in the dietary materials and are known to be capable of interfering with the purpose or conduct of the study if present at levels greater than established by the specifications.
(8) Each dosage level, expressed in milligrams per kilogram of body weight or other appropriate units, of the test or control article to be administered and the method and frequency of administration.
(9) The type and frequency of tests, analyses, and measurements to be made.
(10) The records to be maintained.
(11) The date of approval of the protocol by the sponsor and the dated signature of the study director.
(12) A statement of the proposed statistical methods to be used.
(b) All changes in or revisions of an approved protocol and the reasons therefore shall be documented, signed by the study director, dated, and maintained with the protocol.
[43 FR 60013, Dec. 22, 1978, as amended at 52 FR 33781, Sept. 4, 1987; 67 FR 9585, Mar. 4, 2002]
Text from eCFR as of Sep 1, 2026.
Cited alongside it
Regulations that appear in the same letters as 21 CFR 58.120.
- 21 CFR 58.130Conduct of a nonclinical laboratory study1 letter cites both
- 21 CFR 58.185Reporting of nonclinical laboratory study results1 letter cites both
- 21 CFR 58.190Storage and retrieval of records and data1 letter cites both
- 21 CFR 58.29Personnel1 letter cites both
- 21 CFR 58.33Study director1 letter cites both
- 21 CFR 58.35Quality assurance unit1 letter cites both
Latest letters citing it
The letter citing 21 CFR 58.120 that FDA posted most recently.
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