Risk of interstitial lung disease/pneumonitis; monitor for new or worsening pulmonary symptoms (eg, dyspnea, cough, fever). Risk of hepatotoxicity; monitor liver function tests (including ALT, AST, & total bilirubin) prior to initiation, every 2 wk during the 1st 3 mth of treatment, then once a mth or as clinically indicated. Risk of photosensitivity reactions; limit direct UV exposure during treatment. Patients w/ severe renal impairment (CrCl 15-29 mL/min). Females of reproductive potential & male patients w/ female partners of reproductive potential should use effective contraception during treatment & for 1 wk after the last dose. Pregnancy testing prior to starting treatment; can cause fetal harm when administered to a pregnant woman. Do not breastfeed during treatment & for 1 wk after the last dose. Ped patients.