No safety margin: NOAELs <0.03 mg/kg/day (26-week rat) and <12 mg/kg/day (39-week dog) due to exaggerated pharmacology
“Because of the exaggerated pharmacology in healthy animal models, no safety margins were established at the palovarotene NOAEL doses of <0.03 mg/kg/day and <12 mg/kg/day in the 26-week rat and 39-week dog toxicity studies, respectively (Table 42).”
No NOAEL in 26-week rat: skin, growth plate (knee, sternum) and forestomach findings at all doses
“The target organs were the skin, growth plate of stifle or knee joints and sternum, and nonglandular forestomach during the interim and terminal sacrifices at all doses.”