Permanently discontinue use in recurrent symptomatic or severe ILD/pneumonitis; SJS, TEN or drug-induced hypersensitivity syndrome/DRESS is confirmed. Interrupt dose if new or worsening resp symptoms suspected due to ILD/pneumonitis; severe cutaneous reactions occur. Avoid use in patients w/ or at significant risk of developing Torsade de pointes including those w/ congenital long QT syndrome, uncontrolled or significant cardiac disease, recent MI, heart failure, unstable angina, bradyarrhythmias, uncontrolled HTN & hypothyroidism, high degree AV block, severe aortic stenosis & electrolyte abnormalities. Neutropenia. Monitor serum electrolytes eg, K, Ca, P & Mg prior to & beginning of 1st 6 cycles. Perform ECG prior to initiation & repeat at approx day 14 of 1st cycle; LFTs & CBC before initiation & monitor every 2 wk for 1st 2 cycles, beginning of each subsequent 4 cycles & as clinically indicated. Avoid drugs prolonging QT interval &/or strong CYP3A inhibitors. Avoid use w/ tamoxifen. Breast cancer patients w/ severe renal impairment. Drug-induced liver injury & increased transaminases. May impair male fertility. Women of childbearing potential should use effective contraception during & for at least 3 wk after last dose. Pregnancy. Not to be used during lactation & for at least 3 wk after last dose. Ped.