21 CFR 58.33
Study director
21 CFR 58.33 is the regulation titled “Study director” in 21 CFR Part 58, Good Laboratory Practice for Nonclinical Laboratory Studies. Since 2021, 9 FDA warning letters have cited it.
- Letters citing it
- 9 since 2021
- Jan 1 to Oct 30, 2026
- 1 against 2 on the same dates in 2025
- Most often cited with
- 21 CFR 58.35, in 8 letters
- Closed out
- 22% of these letters have a published close-out
Letters citing it, by year issued
Most are medical device letters (5 of 9). 2026 runs to Oct 30, 2026. Pick a year to see its letters.
What FDA writes when it cites it
The finding headings that cite 21 CFR 58.33 most often, as written in the letters.
- 1 letterFailure of the study director to assure that all experimental data, including observations of unanticipated responses of the test system are accurately recorded and verified [21 CFR 58.33(b)]
The regulation
Read the text of 21 CFR 58.33 (eCFR, as of Sep 1, 2026)
For each nonclinical laboratory study, a scientist or other professional of appropriate education, training, and experience, or combination thereof, shall be identified as the study director. The study director has overall responsibility for the technical conduct of the study, as well as for the interpretation, analysis, documentation and reporting of results, and represents the single point of study control. The study director shall assure that:
(a) The protocol, including any change, is approved as provided by § 58.120 and is followed.
(b) All experimental data, including observations of unanticipated responses of the test system are accurately recorded and verified.
(c) Unforeseen circumstances that may affect the quality and integrity of the nonclinical laboratory study are noted when they occur, and corrective action is taken and documented.
(d) Test systems are as specified in the protocol.
(e) All applicable good laboratory practice regulations are followed.
(f) All raw data, documentation, protocols, specimens, and final reports are transferred to the archives during or at the close of the study.
[43 FR 60013, Dec. 22, 1978; 44 FR 17657, Mar. 23, 1979]
Text from eCFR as of Sep 1, 2026.
Cited alongside it
Regulations that appear in the same letters as 21 CFR 58.33.
- 21 CFR 58.35Quality assurance unit8 letters cite both
- 21 CFR 58.185Reporting of nonclinical laboratory study results5 letters cite both
- 21 CFR 58.202Grounds for disqualification5 letters cite both
- 21 CFR 58.81Standard operating procedures5 letters cite both
- 21 CFR 58.90Animal care4 letters cite both
- 21 CFR 58.130Conduct of a nonclinical laboratory study3 letters cite both
- 21 CFR 58.31Testing facility management3 letters cite both
- 21 CFR 58.190Storage and retrieval of records and data2 letters cite both
Latest letters citing it
The 3 letters citing 21 CFR 58.33 that FDA posted most recently.
- DrugsView Vedic Lifesciences Pvt. Ltd.investigational drug (b)(4)IssuedMar 9, 2026PostedMar 17, 2026
- DevicesView Palamur Biosciences Private Limitednonclinical laboratory studies for medical devicesIssuedDec 11, 2025PostedDec 30, 2025
- DevicesView Jiangsu Kerbio Medical Technology Group Co.nonclinical laboratory testing services for medical devicesIssuedJul 11, 2025PostedAug 26, 2025
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Counts include every citation in a letter, as the Letters filter does. How this database is built.