Vandetanib Disease Interactions

Vandetanib can prolong the QT interval, and its use is contraindicated in patients with congenital long QT syndrome. Additionally, vandetanib should not be used in patients with hypocalcemia, hypokalemia, hypomagnesemia, or long QT syndrome. Care should be exercised when using this agent in patients with ventricular arrhythmias or recent myocardial infarction. It is recommended to correct hypocalcemia, hypokalemia and/or hypomagnesemia prior to starting therapy with vandetanib. Obtain an ECG and serum potassium, calcium, magnesium and TSH at baseline, during treatment, and frequently as necessary.

The use of certain multikinase inhibitors has been associated with pulmonary toxicity. Serious cases of interstitial lung disease (ILD), including fatal cases and interstitial pneumonitis or pulmonary fibrosis have been reported. Caution is recommended when using these agents in patients with a history of interstitial pneumonitis or pulmonary fibrosis or those patients presenting with acute onset of new or progressive unexplained pulmonary symptoms such as dyspnea, cough, and fever pending diagnostic evaluation. If ILD is confirmed, these agents should be permanently discontinued and appropriate measures should be instituted. Treatment should be immediately withheld in patients diagnosed with ILD/pneumonitis and permanently discontinued if no other potential causes of ILD/pneumonitis have been identified.

Heart failure, including fatalities have occurred in patients treated with vandetanib. Monitor for signs and symptoms of heart failure. Consider discontinuation of therapy in patients with heart failure. Close monitoring is recommended.

Serious hemorrhagic events, including fatalities, have occurred in patients treated with vandetanib. Do not administer vandetanib to patients with a recent history of hemoptysis of >= 1/2 teaspoon of red blood. Discontinue treatment in patients with severe hemorrhage.

The use of vandetanib is not recommended for patients with moderate and severe hepatic impairment, as the safety and efficacy of this agent have not been established.

Hypertension, including hypertensive crisis, has occurred in patients treated with vandetanib. Monitor all patients for hypertension and a dose reduction or interruption may be necessary. If hypertension cannot be controlled, do not resume vandetanib. Care should be taken when using this agent in hypertensive patients. Close monitoring is recommended.

Increased dosing of thyroid replacement therapy was required in patients with a prior thyroidectomy. It is recommended to obtain Thyroid-stimulating hormone (TSH) at baseline, during therapy and thereafter as clinically indicated. If signs or symptoms of hypothyroidism occur, examine thyroid hormone levels and adjust thyroid replacement therapy accordingly.

Ischemic cerebrovascular events, including fatalities, occurred in patients treated with vandetanib. The safety of resumption of vandetanib therapy after resolution of an ischemic cerebrovascular event has not been studied. Care should be taken when prescribing this agent to patients at risk. Discontinue treatment in patients who experience a severe ischemic cerebrovascular event.

Vandetanib exposure is increased in patients with impaired renal function. It is recommended to reduce the starting dose in patients with moderate to severe renal impairment and monitor the QT interval closely. There is no information available for patients with end-stage renal disease requiring dialysis.

Reversible posterior leukoencephalopathy syndrome (RPLS), a syndrome of subcortical vasogenic edema diagnosed by an MRI of the brain, has occurred in patients treated with vandetanib. Consider this syndrome in any patient presenting with seizures, headache, visual disturbances, confusion or altered mental function. It is recommended to discontinue therapy in patients developing RPLS.