title: Evaluation of genotoxicity testing of FDA approved large molecule therapeutics.
abstract: Large molecule therapeutics (MW>1000daltons) are not expected to enter the cell and thus have reduced potential to interact directly with DNA or related physiological processes. Genotoxicity studies are therefore not relevant and typically not required for large molecule therapeutic candidates. Regulatory guidance supports this approach; however there are examples of marketed large molecule therapeutics where sponsors have conducted genotoxicity studies. A retrospective analysis was performed on genotoxicity studies of United States FDA approved large molecule therapeutics since 1998 identified through the Drugs@FDA website. This information was used to provide a data-driven rationale for genotoxicity evaluations of large molecule therapeutics. Fifty-three of the 99 therapeutics identified were tested for genotoxic potential. None of the therapeutics tested showed a positive outcome in any study except the peptide glucagon (GlucaGen®) showing equivocal in vitro results, as stated in the product labeling. Scientific rationale and data from this review indicate that testing of a majority of large molecule modalities do not add value to risk assessment and support current regulatory guidance. Similarly, the data do not support testing of peptides containing only natural amino acids. Peptides containing non-natural amino acids and small molecules in conjugated products may need to be tested.
authors.affiliation: Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA 91320, United States. Electronic address: ssawant@amgen.com.
authors.forename: Satin G
authors.initials: SG
authors.lastname: Sawant
authors.affiliation: Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA 91320, United States.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Fielden
authors.affiliation: Comparative Biology and Safety Sciences, Amgen Inc., Thousand Oaks, CA 91320, United States.
authors.forename: Kurt A
authors.initials: KA
authors.lastname: Black
mesh_terms: D017277:Drug Approval; D004348:Drug Labeling; D005934:Glucagon / Q000633:toxicity; D006801:Humans; D008970:Molecular Weight; D009152:Mutagenicity Tests / Q000379:methods*; D010455:Peptides / Q000633:toxicity; D004364:Pharmaceutical Preparations / Q000008:administration & dosage* / Q000737:chemistry; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D014481:United States; D014486:United States Food and Drug Administration
chemical_list: D010455:Peptides; D004364:Pharmaceutical Preparations; D005934:Glucagon
keywords: Antibody-drug conjugate; Biologics; Genetic toxicity studies; ICH S6(R1); Large molecule therapeutics; Monoclonal antibodies; Peptides