No gender differences in neratinib and metabolite M7 exposure were observed in dogs. Metabolite M6 exposure was lower in males compared to females. The Tmax for neratinib and metabolites M6 and M7 ranged from 1 to 6 hr in males and females, respectively. Following a single dose, the elimination half-life (T1/2) of metabolites M6 & M7 were 10 hr for male dogs and 13 hr for female dogs. The elimination half-life (T1/2) of neratinib was ~ 15 hr following multiple oral doses.