Koselugo: genotox, carcinogenicity and repro: done or skipped?

“Selumetinib was not mutagenic or clastogenic in vitro . Selumetinib did result in an increase in micronucleated immature erythrocytes (chromosome aberrations) in mouse micronucleus studies, predominantly via an aneugenic mode of action, but at doses > 160 mg/kg (~38-times the human C max at the clinical dose of 25 mg/m 2 ).”

“Selumetinib was not carcinogenic in a 6-month study in rasH2 transgenic mice and in 2-year carcinogenicity study in rats at exposures ≥ 15 times the human exposure (AUC) at the clinical dose of 25 mg/m 2 .”

“In embryo-fetal development studies in mice at doses > 2.5 mg/kg twice daily (~5-times the human exposure based on area under the curve [AUC] at the clinical dose of 25 mg/m 2 twice daily), selumetinib caused increases in post-implantation loss, a reduction in mean fetal and litter weights, and an increased occurrence of open eye and cleft palate”

“At doses of up to 100 mg/kg selumetinib had no remarkable effects on open field behavior or respiratory parameters in Sprague-Dawley rats. In a cardiovascular safety study in Gottingen minipigs, oral administration of selumetinib twice daily had no remarkable effects on electrocardiograms or circulatory function”