Commissioning GLP toxicology studies

Regulated toxicology is the most expensive and least flexible part of a nonclinical programme. The studies take a fixed time, the capacity to run them is limited, and a study that has to be repeated costs the schedule as well as the money. This article covers what the good laboratory practice declaration in a United States submission actually requires, what drives the schedule, how to read a quotation, and which guidance governs each study in the package.

What the declaration actually requires

The requirement is narrower than it is usually stated. For each nonclinical laboratory study in the application, the sponsor must include a statement that it was conducted in compliance with the good laboratory practice regulation, or, if it was not, a brief statement of the reason for the noncompliance.^[S1] A study conducted outside the regulation is therefore not automatically rejected; what is required is that the position be declared and explained. Compliance is determined study by study rather than held by a facility.^[S2] The practical consequence is a decision to make deliberately for each study: which ones will be run under the regulation, and what the explanation will be for any that are not.

What the regulation buys, beyond the declaration, is reconstructability. It requires standard operating procedures, retention of raw data, and a quality assurance unit that is independent of the staff running the study.^[S2] That is what allows a finding to be traced back years later when a question arises during review. When assessing a laboratory, the useful questions are what the quality assurance unit actually inspects and reports, and how raw data, including electronic records, are retained and would be retrieved.

Schedule and cost

Both the schedule and the price are determined by things that do not appear on the front page of a quotation. The two that matter most are when capacity is booked and what the quoted scope excludes.

Capacity booking and dose range finding

A regulated toxicology study occupies animal rooms, staff and pathology capacity for its full duration, so laboratories schedule them into slots booked well in advance. The start date is usually set by when a slot is available rather than by when the sponsor is ready. Book the slot before the dose range finding work is complete, on the basis that the design may change, rather than after. No figure is given here for typical wait times, because it depends on the laboratory and the species.

Dose range finding studies precede the regulated ones and are normally run outside the regulation, which makes them faster and cheaper. Their purpose is to set the doses for the definitive study, and getting them wrong is the most common cause of a repeat: a top dose set too low produces a study with no findings and no margin, and one set too high produces a study that cannot be interpreted. Running the range finding work at the same laboratory that will run the definitive study removes one source of variability between the two.

Reading a quotation

Quotations are comparable only when they cover the same scope, and they frequently do not. Establish what triggers a change order, whether animal purchase and husbandry are included, whether the price covers the pathology read and any peer review of it, what the report includes, and who pays if the study has to be repeated for a reason attributable to the laboratory. A low quotation with a broad change-order clause is not a low price.

Which guidance governs which study

The concrete form of this question is whether the laboratory designs each study against the guidance that governs it. That is checkable, unlike a general claim to expertise.

• {'items': ['Repeat-dose toxicology: duration tied to the intended clinical trial duration, in two mammalian species, one of them a non-rodent.^[S3]', 'Safety pharmacology: the core battery covering central nervous, cardiovascular and respiratory function, with a separate assessment for delayed ventricular repolarization.^[S4]', 'Genotoxicity: the standard assay combinations and the interpretation of a positive result in one of them.^[S5]', 'Reproductive and developmental toxicology: which studies are needed before which clinical stage depends on the population to be enrolled.^[S6]', 'Carcinogenicity: whether long-term rodent studies are needed at all is itself a guidance question, decided from the intended treatment duration and other factors.^[S7]', 'Biotechnology-derived products: a different framework applies, and species selection is the constraining decision.^[S9]', 'Products for advanced cancer: a different package again, with some studies required at marketing application rather than before clinical work.^[S8]']}

Experience with the modality matters because the applicable guidance differs by modality, not merely because familiarity helps. A laboratory that has run antibody programmes will have dealt with the species selection problem that arises when a biologic is active in only one species,^[S9] and one that has run oncology programmes will know which studies that framework moves to the marketing application stage.^[S8] Ask which programmes of this modality the laboratory has supported and what questions the agency raised, rather than asking whether it has experience.

The other capability worth establishing is what happens when an unexpected finding appears. Ask what additional analysis the laboratory can run on retained material without a new study, how quickly, and whether that is inside the quoted scope or a change order. This is the situation in which the difference between laboratories is most visible, and it is not visible in a quotation.

Summary

The schedule is set by when capacity is booked, not by study duration. The price is set by what the quoted scope excludes, not by the headline figure. And whether the study will be usable is set by which guidance it was designed against, and by whether the compliance position was decided deliberately rather than assumed.^[S1]

This article does not claim that a more expensive laboratory costs less overall; that depends on the programme and no source establishes it generally. What can be said is narrower. Each of the checks above is answerable before award, from documents the laboratory can produce and from a public inspection database,^[S10] and a selection made on those answers rests on something firmer than a claim of expertise.

About this article

This is an independent editorial article for people who commission nonclinical work in the United States. Regulatory citations are to the Code of Federal Regulations as published; guidance documents describe the agency current thinking and are not binding. This site does not recommend any laboratory and receives no compensation from the companies it describes. Last reviewed: September 3, 2026.

References

1. 21 CFR 312.23(a)(8)(iii) — For each non-clinical study, a statement of GLP compliance—or, in cases of non-compliance, a brief explanation of the reason—is required. https://www.govinfo.gov/content/pkg/CFR-2023-title21-vol5/xml/CFR-2023-title21-vol5-sec312-23.xml (accessed 2026-09-03)
2. 21 CFR Part 58 — Good Laboratory Practice for Nonclinical Laboratory Studies (§58.1 scope; §58.35 quality assurance unit; §58.81 standard operating procedures; §58.185 final report). https://www.ecfr.gov/current/title-21/chapter-I/subchapter-A/part-58 (accessed 2026-09-03)
3. FDA — ICH M3(R2) Nonclinical Safety Studies for the Conduct of Human Clinical Trials and Marketing Authorization for Pharmaceuticals, January 2010. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/m3r2-nonclinical-safety-studies-conduct-human-clinical-trials-and-marketing-authorization (accessed 2026-09-03)
4. FDA — ICH S7A Safety Pharmacology Studies for Human Pharmaceuticals, April 2001, and ICH S7B (Non-clinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation)), October 2005. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/s7a-safety-pharmacology-studies-human-pharmaceuticals (accessed 2026-09-03)
5. FDA — ICH S2(R1) Genotoxicity Testing and Data Interpretation for Pharmaceuticals Intended for Human Use, June 2012. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/s2r1-genotoxicity-testing-and-data-interpretation-pharmaceuticals-intended-human-use (accessed 2026-09-03)
6. FDA — ICH S5(R3) Detection of Reproductive and Developmental Toxicity for Human Pharmaceuticals, May 2021. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/s5r3-detection-reproductive-and-developmental-toxicity-human-pharmaceuticals (accessed 2026-09-03)
7. FDA — ICH S1A The Need for Long-term Rodent Carcinogenicity Studies of Pharmaceuticals, March 1996（connection: S1B, July 1997、S1C(R2), September 2008）. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/s1a-need-long-term-rodent-carcinogenicity-studies-pharmaceuticals (accessed 2026-09-03)
8. FDA — ICH S9 Nonclinical Evaluation for Anticancer Pharmaceuticals, March 2010. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/s9-nonclinical-evaluation-anticancer-pharmaceuticals (accessed 2026-09-03)
9. FDA — ICH S6(R1) Preclinical Safety Evaluation of Biotechnology-Derived Pharmaceuticals. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/s6-r1-addendum-preclinical-safety-evaluation-biotechnology-derived-pharmaceuticals (accessed 2026-09-03)
10. FDA — Inspection Classification Database（Update and publish facility inspection classifications on a weekly basis.）. https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/inspection-classification-database (accessed 2026-09-03)