A practical guide to transitioning from exploratory studies to GLP toxicology when outsourcing your non-clinical safety program to a specialist GLP toxicology CRO.

Demonstrating efficacy in a disease model represents a major milestone in preclinical drug development. Whether your compound reduces tumour burden in an oncology model, improves cognition in a mouse model of Alzheimer’s disease, or restores muscle function in Duchenne muscular dystrophy mice, efficacy data provide the first indication that your therapeutic approach has biological potential to treat the indicated disease.  

However, efficacy alone is not sufficient to support a regulatory submission.  

Before a novel therapeutic can enter First-in-Human (FIH) clinical trials, regulatory authorities require evidence that the compound can be administered safely. Accordingly, generating these safety data marks the transition from exploratory research into regulatory preclinical development. 

For many sponsors, particularly first-time biotech companies, one question frequently arises at this stage: when is it time to move from exploratory in vivo studies to Good Laboratory Practice (GLP) toxicology?  

Understanding this transition early can help you prevent unnecessary delays, repeated studies, and costly regulatory questions later in development.  

In this blog post, we discuss how exploratory and GLP studies complement each other, when a program is ready to transition into GLP toxicology, and how GLP principles ensure that preclinical safety data are scientifically robust and suitable for regulatory decision-making.  

Lastly, we outline how outsourcing your GLP toxicology studies to a specialist European CRO can accelerate your path to IND submission without compromising data integrity.  

First things first: Would you be comfortable defending your nonclinical data package to a regulatory authority today? 

Before transitioning from exploratory studies to GLP toxicology, you should evaluate whether your current nonclinical data package is sufficiently robust to support regulatory discussions and an IND-enabling development pathway. 

The wrong study selection can jeopardize both your budget and your timeline.  

Therefore, a useful principle when planning a nonclinical data package is: 

• Nonclinical studies that primarily support safety assessment and the selection of a safe human starting dose should be conducted under GLP conditions. 

• Nonclinical studies primarily designed to demonstrate biological mechanism of action or efficacy can generally be conducted under non-GLP conditions. 

At InnoSer, we help you assess where you are in your nonclinical development and determine what data are still needed before you are ready to move into GLP toxicology territory. Together, we can identify the studies that need to be performed, what can be addressed through exploratory work, and how to build a focused program that supports the next development milestone without unnecessary studies, costs, or delays. 

Exploratory nonclinical studies: defining the right path before entering GLP toxicology 

Exploratory in vivo studies provide the foundation for a successful GLP toxicology program. Although these studies are not intended to generate definitive regulatory safety data, they provide critical information required to design appropriate GLP studies. 

Exploratory studies are designed to answer biological and scientific questions: 

• Does the compound engage the intended target?  

• Does the therapeutic produce the expected disease-modifying effect?  

• What dose range produces biological activity?  

• How is the compound absorbed, distributed, metabolized and eliminated in vivo? 

They also offer greater flexibility in terms of timelines and budget. Accordingly, exploratory studies can be conducted faster and at a lower cost than formal GLP studies, allowing you to generate the information needed to make informed decisions before committing to a larger, and more costly, regulatory program. This flexibility can help you identify potential issues early on, refine your study design, and most importantly, avoid unnecessary investment in a GLP program before the key scientific questions have been addressed.  

At InnoSer, we support you throughout this transition, helping you build on the data you already have and design the next stage around specific requirements of your drug development program.  

Once you’ve answered these questions, and your drug development path is now well-defined, your drug development program can finally move onto the next stage: formal nonclinical GLP toxicology testing.  

GLP toxicology studies: generating regulatory-compliant safety data to support First-in-Human (FIH) studies 

Once your drug candidate has reached a stage where the therapeutic strategy, formulation, and development pathway are sufficiently defined, the focus shifts from exploration to regulatory safety assessment. 

Accordingly, toxicology studies performed under GLP guidelines are designed to answer regulatory safety questions, such as: 

• What adverse effects occur following single and repeated exposure?  

• Which organs or systems may be affected?  

• What exposure levels are tolerated?  

• What dose can safely support clinical development? 

By building on the insights generated during exploratory non-GLP studies, a well-designed GLP toxicology program provides the robust safety data needed to support regulatory submissions and confidently advance a drug candidate into FIH studies. 

Why do regulatory authorities demand GLP-quality data in IND and NDA submission packages? 

The importance of GLP can be traced back to a landmark moment in regulatory toxicology history. In 1976, the FDA identified major discrepancies in the preclinical study documentation of Industrial Bio-Test Laboratories (IBT), at the time one of the largest preclinical testing facilities in the United States.  

Subsequent inspections revealed significant deficiencies in study documentation, data integrity, and laboratory practices, a situation described by FDA inspectors as “the swamp”. 

These findings highlighted the need for a structured quality framework to ensure that regulatory decisions are based on reliable and reproducible scientific data.  

In response, the FDA introduced GLP regulations in 1978, establishing standards for how non-clinical safety studies should be planned, conducted, documented, and reported. 

Today, GLP remains a cornerstone of regulatory preclinical development, with key benefits:  

• Improves data quality and reliability 

• Reduces errors and inconsistencies 

• Ensures complete and accurate record keeping 

• Facilitates regulatory acceptance (worldwide) of study results (generated once) 

• Enhances confidence in laboratory findings 

• GLP ensures that laboratory studies are conducted in a well-organized, documented, and quality-controlled manner, producing trustworthy and reproducible results  

Ultimately, studies performed in accordance with GLP principles provide regulatory authorities with confidence that your nonclinical safety data have been generated, documented, and reported according to established quality standards, with appropriate traceability and data integrity. 

However, GLP compliance alone does not determine the scientific validity of a study. Sound study design, appropriate methodologies, scientific expertise, and early engagement with regulatory authorities are equally important in generating meaningful data to support the development of a drug candidate. 

A common misconception: GLP does not define what should be tested; it defines how studies are conducted 

A common misconception is that GLP represents a specific type of toxicology study. In reality, GLP is a quality framework describing how nonclinical safety studies should be planned, performed, documented, reported, and archived.  

GLP does not determine: 

• which therapeutic target should be investigated,  

• which animal model should be selected,  

• which endpoints should be measured,  

• or which dose should be tested.  

Instead, GLP ensures that the generated data are reliable, traceable, and suitable for regulatory review. Regulatory authorities, sponsors, and research organizations must be able to rely on the integrity and quality of study results. 

This is why working with an experienced preclinical GLP-certified toxicology CRO can be critical when planning your nonclinical drug development strategy. The right preclinical GLP toxicology CRO does more than conduct a study according to GLP requirements; it can work alongside you to determine the most appropriate study design, model, endpoints, dosing strategy, and overall approach based on the scientific and regulatory objectives of the program. 

At InnoSer, our preclinical experts work closely with you to translate these objectives into scientifically sound study designs. From selecting appropriate models and endpoints to defining dosing strategies and planning the transition from exploratory studies to GLP toxicology, we combine scientific expertise with regulatory and operational experience to help ensure that each study generates meaningful data for the next stage of development. 

Have questions about your nonclinical development strategy? Get in touch with our team to discuss how we can support your next step.

ALCOA+ is no mysterious coding: Why GLP enhances data integrity and therefore the trustworthiness of your preclinical data quality  

When preparing a nonclinical data package for regulatory submission, generating high-quality scientific data is only one part of the process. Regulatory authorities must also have confidence that the data were generated, documented, and maintained in a way that ensures reliability and traceability throughout the study lifecycle. 

This is where data integrity becomes critical. 

Under GLP, data integrity is supported by the ALCOA+ principles. Despite the technical name, the concept is straightforward: every important piece of information generated during a study should be attributable, traceable, accurate, and available when needed for regulatory review. 

The ALCOA+ principles help ensure that your study data are not only scientifically meaningful, but also trustworthy: 

• Attributable: who made the entry or made a change when 

• Legible: permanent readable und understandable 

• Contemporaneous: document the actions timely  

• Original: firsthand documentation counts 

• Accurate: documentation is true and correct 

• +Complete: no relevant information is missing 

• +Consistent: documentation is logical and in correct order 

• +Enduring: data and documentation is safe the whole lifecycle long including archiving for about 15 years 

• +Available: data and documents must be available for audits and inspections. 

At InnoSer, data integrity is embedded throughout our GLP workflows, with controlled processes and documentation practices designed to ensure that study data remain accurate, traceable, and inspection ready.  

If you are planning a GLP toxicology program and want to ensure your data meet both scientific and regulatory expectations, our team can help you define and implement the right approach. 

GLP quality does not happen by chance: How contracting laboratories build confidence in preclinical data — and why outsourcing to the right GLP toxicology CRO partner matters 

A successful GLP study is not defined only by the final report. Behind every regulatory-ready preclinical package is a structured quality system involving multiple teams, defined responsibilities, independent oversight, and continuous review throughout the entire study lifecycle. 

GLP compliance requires more than following a study protocol. It requires that every step, from study planning and experimental procedures to data review, reporting, and archiving, is performed according to predefined processes and documented in a traceable manner. 

During GLP inspections, regulatory authorities evaluate whether a facility has the appropriate systems in place to generate reliable and reproducible nonclinical data. This includes reviewing toxicology study processes, quality systems, data governance practices, computerized systems, and the validation and application of bioanalytical methods supporting non-clinical studies.  

Particular attention is given to the traceability, reliability, and integrity of data generated throughout the study lifecycle. 

Evaluating compliance with GLP principles and internationally recognised bioanalytical standards ensures that your nonclinical data are scientifically robust, reproducible, and suitable to support regulatory decision-making. 

Therefore, partnering with an experienced GLP facility allows sponsors to access these capabilities while maintaining focus on their core scientific programs. 

At InnoSer, we work closely with sponsors throughout the study lifecycle, combining experienced toxicology teams, established quality systems, independent quality oversight, and robust data management practices to ensure that each study is conducted and documented to the required GLP standards. By taking responsibility for the operational and quality aspects of the study while keeping sponsors closely involved, we help ensure that the resulting data are reliable, traceable, and ready to support the next stage of development and regulatory review. 

The people behind your GLP toxicology study: Players, referees, and the teams ensuring data integrity

A GLP toxicology study is not driven by a protocol alone. Behind every regulatory-ready preclinical package is a multidisciplinary team responsible for study execution, scientific oversight, quality assurance, and data integrity. 

At InnoSer, our GLP teams work as an extension of your development team, combining scientific expertise, regulatory understanding, and quality oversight to support the successful execution of your toxicology program.  

The players: conducting the study 

The referees: independent oversight of study integrity

From disease models to exploratory research and GLP toxicology: How InnoSer supports your regulatory development pathway journey to the clinic

Following the acquisition of Vivo Science, InnoSer has expanded its preclinical capabilities to include GLP toxicology expertise, enabling you to progress from exploratory research towards regulatory studies within a connected development pathway. 

For many biotech and pharmaceutical companies, the transition from efficacy studies into GLP toxicology represents a critical step in development. However, moving between providers can introduce challenges, including transfer of study knowledge, alignment of documentation, and maintaining consistency in scientific strategy. 

Therefore, by combining InnoSer’s expertise in exploratory in vivo disease models with Vivo Science’s GLP toxicology capabilities, sponsors can benefit from a more integrated approach to preclinical development. From early study design onwards, programs can be developed with regulatory expectations in mind, supporting a smoother transition from exploratory studies to regulatory safety packages. 

This integrated approach helps reduce unnecessary handovers, minimise duplication, and maintain continuity of scientific knowledge throughout the preclinical development journey. 

Planning your transition from exploratory studies to GLP toxicology? Contact our scientific team to discuss your preclinical development strategy and how we can support your program from early in vivo studies through regulatory-ready safety packages.