tokens: METHODS : Seventeen subjects who were genotyped as CYP2D6 extensive metabolizers were enrolled in this randomized , open - label , crossover study to receive a single oral dose of desipramine ( 50 mg ) on two separate occasions , once alone and once after multiple doses of cinacalcet ( 90 mg for 7 days ). Blood samples were obtained predose and up to 72 h postdose .