What Makes a Good Preclinical Study Final Report?

When it comes to meeting deadlines and continuing to receive investments, the timely review of your GLP preclinical final report is very important. Timelines are generally tight, and your report is not the only study that a reviewer* is working on. So, how do you compile a report that is both detailed enough to gain approval, yet easy enough to read that it moves through the review process efficiently?

Based on decades of collective experience conducting preclinical studies and writing both GLP and non-GLP final reports, our team of subject matter experts have outlined what they believe makes a good preclinical study report.

*Note: The term “reviewer” in the context of this article refers to any individualized reviewing the results of a preclinical study to include investors/due diligence teams for funding, grant agencies, regulatory bodies, preclinical consultants, study directors, etc.

Write a Detailed Executive Summary

Your executive summary should help the reviewer (regulatory body or other) get a lay of the land and focus on the most important date by:

• Discussing the background of the test article and why the study was conducted

• Laying out why the study was conducted

• Summarizing the objectives, methods, results, and conclusion in paragraph format
  
  

Sections of the Report

Personnel

This describes all individuals involved in the study from the study director to the husbandry technician. Be sure to include all credentials. An important part of 21-CFR part 58) is the use of “qualified personnel in the study.” Having credentials helps reviewers know that the individuals with the appropriate expertise performed the study.

Objectives

List all specific objectives from the protocol. Do not summarize. For example: “The objective of this study was to evaluate the safety of the test article. Safety was determined using the following criteria: absence of adverse events, 5% or less mortality, absence of thrombi.”

Enrollment Table

Include a table describing the number of animals, animal identification, implant and explant dates, any follow-up dates, early mortalities and scheduled termination. Overall duration on study for each animal should be considered for chronic studies.

Test Article Description  

Describe the test article — your device or product — even though you also describe it in the protocol. Pictures are helpful, too.

Test Article Use and Disposition

A table here is handy. List lot numbers, manufacturing dates, implant dates and specific animal numbers.

Test Article Characterization

The CFR requires that the test article characterization be established. For devices, this means everything from sterility certificates, build records, lot travelers, expiration/stability data etc. Be sure to reference where this data can be found, and attach it in the appendix.

Animal Source and History

Healthy animals from approved vendors are a requirement of a good preclinical study. List the USDA approved vendor’s phone number, name and address. List whether or not the animals have a history of prior use and their condition at the time of the study.

Related regarding animal models: Beyond documenting animal source and history, your final report benefits when the preclinical model was strategically selected from the beginning. When model selection is treated as an afterthought or based solely on availability, final reports often must explain anatomical mismatches, protocol amendments to accommodate unexpected model limitations, or compromised data from models that were 'close enough' but not optimal. Strategic model selection—particularly for interventional devices requiring precise anatomical equivalence—produces cleaner final reports with fewer deviations to justify and more straightforward results to present. This upfront strategic decision makes report writing easier and regulatory review smoother. Learn how strategic preclinical model selection impacts study outcomes.

Methods

This is another important section. The methods generally describe how everything in the study was conducted. This includes procedural steps and frequency for implant, follow up and explant procedures, physical exams, body weights, clinical pathology, histopathology, gross pathology, daily observations, or any other procedure or analysis that was performed during the study. Any discrepancies from what the protocol laid out and what was performed should be detailed in logged deviations and referenced in the text accordingly.

Context & Related Content (October 2025) - A note about the value of in-house histopathology for preclinical studies & reports.

How histopathology is conducted—whether in-house or outsourced—significantly impacts the quality and comprehensiveness of this section. When preclinical CROs have integrated, in-house histopathology capabilities, pathologists participate in protocol development from the start, ensuring tissue sampling strategies, evaluation timepoints, and analytical approaches are optimized before procedures begin. This early involvement prevents protocol deviations and amendments that complicate final report writing, produces more detailed and accurate methods descriptions, and ensures seamless coordination between procedural teams and pathology teams throughout the study. The result is a methods section that regulatory reviewers can follow confidently, with fewer discrepancies to explain. Discover why in-house histopathology integration produces better final reports.

Results

The highest focus! This section should contain all the results from the study, good and bad. Any unanticipated event or finding has to be explained whether it was related to the intended use of the test article. Tables and pictures come in handy in this section. While its important to attach appendices of pertinent data or contributing scientist reports, it is important to summarize all raw data in a meaningful way within the body of the main report. This ensures the reviewer doesn’t have to “go fishing” in the appendices. Failure to include a raw data summary within the body of the main report will frustrate the reviewer, require additional time spent “searching,” and delay the process.

For example: If you have attached a contributing scientist’s histopathology report, ensure you have at least included a summary of those results and some representative pictures in the main body of the report as opposed to “see appendix C.” This is a top area of frustration for reviewers! When describing amendments and deviations, it is important to focus on why, how and if they impacted the quality and integrity of the data and/or the animals’ health and wellbeing or study outcomes. It is important to provide this analysis and describe it in the body of the report in addition to the copies of the amendments and deviations.

Context & Related on Histopathology Reports (October 2025)
Outstanding histopathology reports provide group-based analysis that supports regulatory decision-making, include carefully selected annotated photomicrographs that tell the visual story of device-tissue interactions, offer expert interpretation beyond mere observation, and detail transparent scoring methodologies. Since many regulatory reviewers aren't pathologists, these elements serve as crucial evidence that studies were properly conducted and help answer questions before they're even asked. When summarizing histopathology findings in your main report body, ensure you capture these interpretive elements—not just raw scores—to give reviewers the context they need. Learn what separates outstanding histopathology reports from merely adequate ones.

Discussion and Conclusions

The discussion and conclusions section of a GLP preclinical report are of equal significance as the results section. Occasionally, study results are not straightforward. That does not mean that the study was not successful. The discussion describes what influenced or influences results and helps the reviewer understand confounding results.

It’s unrealistic to expect the reviewer to make their own conclusions. We’ve read reports with one-line conclusions stating “The study was successful. No deaths.” This is not helpful nor funny in a review situation. The conclusions need to state very clearly whether or not the specific objectives of the study were accomplished.

For example: if one objective is absence of adverse events, then, state that based on the results no adverse events were observed. If you have 10 objectives, ensure that every one is stated as fulfilled or not fulfilled in COMPLETE SENTENCE FORMAT. Include the conclusions from contributing scientists’ reports.

When there is a critical, overarching objective like safety, ensure that is also detailed. For example, “this device was found to be safe in the porcine model.” Do not state “See results” in this section. Sometimes conclusions are not straightforward. That is okay. State the facts. Do not exclude data. Never try to make data fit the objectives.