“The target organs for istradefylline in rats and dogs are consistent and are the adrenal gland (hypertrophy/hyperplasia) and lung (pneumonitis with septal thickening).”
✓ VerifiedFDA pharmacology/toxicology review, p. 29Source ↗
Why that species
No novel human metabolites relative to rat and dog
“In human studies, MI was the primary metabolite and no novel metabolites were identified when compared to the rat and dog data.”
✓ VerifiedFDA pharmacology/toxicology review, p. 39Source ↗
Surrogate molecule
No surrogate; the clinical compound was tested
“Brain mineralization was not detected in mice administered istradefylline (0, 25, 125, or 250 mg/kg/day) orally for two years or in dogs administered istradefylline (0, 10, 30, or 100 mg/kg/day) orally for 52 weeks.”