An Investigational New Drug (IND) application is the regulatory gateway that allows a drug candidate to advance from preclinical development into first-in-human clinical trials. Before that application reaches the FDA, sponsors must compile a comprehensive body of preclinical evidence demonstrating that the compound is safe enough to test in humans and that the proposed clinical protocol is scientifically sound.
IND-enabling studies are the preclinical experiments specifically designed to meet FDA requirements outlined in 21 CFR Part 312. They span pharmacology, toxicology, pharmacokinetics, and manufacturing quality — each producing data that directly informs the IND submission package. For biotech companies and academic sponsors navigating this process for the first time, understanding the scope and sequencing of these studies is critical to avoiding costly delays.
At InfinixBio, our preclinical team partners with sponsors at the IND-enabling stage to design, execute, and interpret the studies needed to support a complete submission.
The FDA expects a well-organized IND to address several interconnected areas of preclinical evidence. Sponsors should anticipate that each area requires both primary data generation and formal report writing.
Primary pharmacology data demonstrates that the drug candidate produces the intended biological effect. This typically includes target engagement assays, mechanistic proof-of-concept experiments in relevant cell lines or animal models, and dose-response characterization. Secondary pharmacology work evaluates off-target activity that could predict safety risks before human exposure begins.
The FDA requires safety pharmacology assessments covering central nervous system, cardiovascular, and respiratory function at minimum (ICH S7A guidance). Cardiovascular studies, especially hERG channel assessment, are a common gating factor for IND timelines and should be planned early rather than treated as a checkbox at the end of development.
Understanding how a compound is absorbed, distributed, metabolized, and excreted is foundational to both dose selection and safety interpretation. InfinixBio’s pharmacokinetic analysis services generate the in vitro and in vivo PK data needed to support starting dose calculations and exposure multiples in toxicology studies.
Toxicology is typically the most time- and resource-intensive component of IND-enabling work. For a standard small molecule entering a Phase 1 oncology trial, the FDA generally expects:
Toxicology studies conducted under GLP compliance (Good Laboratory Practice, per 21 CFR Part 58) are required for pivotal IND-enabling studies.
In vitro assay development and early pharmacology data inform species selection for downstream animal work. Running toxicology studies in a pharmacologically irrelevant species wastes significant resources and may generate uninterpretable safety data.
Toxicology study doses are set based on PK projections and maximum tolerated dose estimates. Sponsors who initiate GLP tox studies without completed PK data risk selecting inappropriate doses, failing to achieve adequate exposure multiples — a critical FDA expectation.
GLP studies require formal study reports reviewed and signed by the study director and QA unit before inclusion in an IND. This process adds four to eight weeks to the calendar after raw data is collected.
InfinixBio is structured to support preclinical sponsors across the full IND-enabling scope. Our team’s expertise spans bioanalytical method development and validation for exposure measurement, in vivo pharmacology and toxicology, and dose range-finding studies that precede formal GLP work. We maintain BSL Level II laboratory facilities with a team that is 38% PhDs and holds 60+ issued and pending patents.
We are transparent about scope: InfinixBio does not conduct regulatory affairs submissions or clinical data management. Our focus is on generating the high-quality preclinical data that sponsors bring to those downstream activities. Learn more about our IND-enabling study support.
Contact InfinixBio today to discuss your preclinical program and how we can help you build a complete IND package.
Most small molecule IND packages require toxicology data from two species: one rodent (typically rat) and one non-rodent (typically dog or non-human primate). The appropriate non-rodent species depends on pharmacological relevance and metabolic similarity to humans. For biologics, the FDA may accept single-species tox if only one species is pharmacologically relevant.
Not all studies. Exploratory pharmacology, early ADME screening, and dose range-finding studies are commonly conducted as non-GLP. The FDA requires GLP compliance for pivotal safety pharmacology and toxicology studies cited directly in the IND submission. Sponsors should clearly designate which studies are pivotal before contracting a CRO.
A Pre-IND meeting (Type B) is a voluntary interaction with the FDA before the IND is filed, used to align on study design and data expectations. The IND submission triggers a 30-day FDA review period, after which the sponsor may proceed to clinical trials unless the FDA places a clinical hold. Pre-IND meetings reduce the risk of clinical holds by surfacing FDA expectations early.
Our experienced lab team is here to help. Reach out today to learn more.
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