Modality determines the nonclinical package

Two products can act on the same target and need almost nothing in common nonclinically. What a programme has to do is set less by the target than by what the molecule is: an orally dosed small molecule, a protein given by infusion, an oligonucleotide, or a population of living cells. Each article here takes one modality and sets out what it changes.

Three frameworks, and which one applies is not always obvious

A small molecule is developed against the general nonclinical safety guidance, which sets out what is needed before each clinical phase.^[S1] A biologic is developed against the guidance for biotechnology-derived products, where the first decision is a species in which the product is pharmacologically active at all.^[S2] A cell or gene therapy product falls outside the scope of the ICH safety guidances entirely, as the FDA's own guidance for those products states.^[S3] Describing a cell therapy programme as compliant with the biotechnology guidance is therefore inaccurate without a qualification, and settling which framework applies is a question for a pre-application meeting rather than an assumption.

Articles in this section (19)

• Antibody-Drug Conjugates: Linker Chemistry, Multi-Analyte Bioanalysis, and the FDA Guidance — linker chemistry, multi-analyte bioanalysis, and the FDA guidance specific to this format
• Anti-HER2 Antibodies: Target-Related Cardiotoxicity, Expression Heterogeneity, and Species Selection — cardiotoxicity that comes from the target itself, and expression heterogeneity
• Anti-PD-1 Antibodies: What the Approved Labels Say About Their Nonclinical Packages — what the approved labels record about the animal studies behind them
• Anti-VEGF Agents in Oncology: Target-Related Toxicity and What the Monkey Studies Found — the reproductive and renal findings in the monkey studies
• Antisense Oligonucleotides: Nonclinical Distribution, Pharmacology, and Safety Assessment — distribution, class effects, and safety assessment for oligonucleotides
• BCR-ABL Inhibitors: Resistance Models, Exposure, and Cardiovascular Safety Assessment — resistance models, exposure, and cardiovascular safety assessment
• BTK Inhibitors: Nonclinical Assessment of Covalent and Noncovalent Agents — covalent and noncovalent agents, assessed differently
• CAR-NK Cell Therapy: Product Design and Nonclinical Assessment — product design and nonclinical assessment for engineered NK cells
• CAR T Cell Products: Which FDA Framework Applies, and Why the ICH Safety Guidances Do Not — why the ICH safety guidances do not apply, and what does
• Cyclic Peptides: Permeability, Peptide Stability, and Immunogenicity Assessment — permeability, peptide stability, and immunogenicity
• EGFR Inhibitors: Resistance Mechanisms, Target-Related Toxicity, and Two Very Different Modalities — resistance mutations, and why the antibodies against this target need a different package
• Embryonic Stem Cell-Derived Products: Tumorigenicity and Nonclinical Assessment — tumorigenicity and residual undifferentiated cells
• GLP-1 Receptor Agonists: The Class Boxed Warning, the Species Problem, and What the Labels Record — the class boxed warning every approved product carries, and the species question behind it
• iPSC-Derived Cell Products: Two Regulatory Frameworks at Once, and the Tumorigenicity Study That Must Use the Clinical Product — two product frameworks at once, and the study that must use the clinical product
• Macrocyclic Drugs: Chameleonicity, Drug Interactions, and Tissue Exposure — conformational behaviour, interactions, and tissue exposure
• mRNA Therapeutics: Which Regulatory Framework Applies, and What the Delivery Vehicle Adds — which framework applies, and what the lipid vehicle adds to the assessment
• Mesenchymal Stromal Cell Products: Potency, Biodistribution, and Nonclinical Assessment — potency definition and biodistribution
• siRNA Development: Seed-Region Off-Target Effects, Hepatocyte Delivery, and What the Approved Labels Show — seed-region off-target silencing, and hepatocyte delivery
• TCR-Engineered T-Cell Therapy: Cross-Reactivity and Nonclinical Assessment — cross-reactivity screening against normal tissue

References

1. FDA — ICH M3(R2) Nonclinical Safety Studies for the Conduct of Human Clinical Trials and Marketing Authorization for Pharmaceuticals. 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)
2. 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)
3. FDA (CBER/OCTGT) — Preclinical Assessment of Investigational Cellular and Gene Therapy Products（2013/11）. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/preclinical-assessment-investigational-cellular-and-gene-therapy-products (accessed 2026-09-03)