Negative in Ames, in vitro TK6 micronucleus and in vivo rat micronucleus assays
“Ensitrelvir was not genotoxic in the reverse mutation bacterial (Ames) test, in vitro micronucleus assay using human lymphoblastoid TK6 cells, or the in vivo rat micronucleus assays.”
✓ VerifiedFDA pharmacology/toxicology review, p. 13Source ↗
Carcinogenicity
Not conducted (short treatment duration)
“Carcinogenesis studies were not conducted due to the short duration of drug administration.”
✓ VerifiedFDA pharmacology/toxicology review, p. 13Source ↗
Instead of carcinogenicity
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Instead of genotoxicity
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
DRG histopathology
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Reproductive & developmental
Rabbit EFD: axial skeletal malformations, embryofetal lethality and abortion with maternal toxicity (NOAEL 30 mg/kg/day, 3x)
“In rabbits, malformations and variations of the axial skeleton, embryofetal lethality, abortion, and post-implantation loss, accompanied by maternal toxicity were observed, with a NOAEL of 30 mg/kg/day and a safety margin of 3X.”
✓ VerifiedFDA pharmacology/toxicology review, p. 7Source ↗
Safety pharmacology
No adverse CV, respiratory or CNS effects; hERG 39% inhibition at 100 µM, low QT risk
“There were no adverse effects in any of the cardiovascular, respiratory, and central nervous system assessments in dogs and rats. In the hERG assay, the maximum tested concentration of 100 µmol/L inhibited the hERG current by 39%, which was not considered significant and suggested a low risk for QT prolongation.”
✓ VerifiedFDA pharmacology/toxicology review, p. 11Source ↗
Genotox: Ames
Negative
“Ensitrelvir was not genotoxic in the reverse mutation bacterial (Ames) test, in vitro micronucleus assay using human lymphoblastoid TK6 cells, or the in vivo rat micronucleus assays.”
✓ VerifiedFDA pharmacology/toxicology review, p. 13Source ↗
Genotox: in vitro mammalian
In vitro micronucleus (human TK6 cells): negative
“Ensitrelvir was not genotoxic in the reverse mutation bacterial (Ames) test, in vitro micronucleus assay using human lymphoblastoid TK6 cells, or the in vivo rat micronucleus assays.”
✓ VerifiedFDA pharmacology/toxicology review, p. 13Source ↗
Genotox: in vivo
Rat micronucleus: negative
“Ensitrelvir was not genotoxic in the reverse mutation bacterial (Ames) test, in vitro micronucleus assay using human lymphoblastoid TK6 cells, or the in vivo rat micronucleus assays.”
✓ VerifiedFDA pharmacology/toxicology review, p. 13Source ↗
Carcinogenicity model
Not conducted (five-day human dosing)
“conducted due to the short duration (five days) of drug administration in humans.”
✓ VerifiedFDA pharmacology/toxicology review, p. 8Source ↗
Carcinogenicity timing
Not required: short treatment duration
“Carcinogenesis studies were not conducted due to the short duration of drug administration.”
✓ VerifiedFDA pharmacology/toxicology review, p. 13Source ↗
“In the hERG assay, the maximum tested concentration of 100 µmol/L inhibited the hERG current by 39%, which was not considered significant and suggested a low risk for QT prolongation.”
✓ VerifiedFDA pharmacology/toxicology review, p. 11Source ↗
Not genotoxic overall: Ames negative; in vitro chromosome aberration positive without (not with) metabolic activation; rat micronucleus and comet negative