ANAGRELIDE Drug Interactions: What You Need to Know

INTERACTIONS Other PDE 3 inhibitors: Exacerbation of inotropic effects (7.2) Aspirin and Drugs that Increase Bleeding Risk: Increased risk of bleeding with concomitant use (7.3)

7.1 Drugs that Prolong QT Avoid use of anagrelide in patients taking medications that may prolong QT interval (including, but not limited to, chloroquine, clarithromycin, haloperidol, methadone, moxifloxacin, amiodarone, disopyramide, procainamide, and pimozide) <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) and Clinical Pharmacology (12.2)]</span> .

7.2 PDE3 Inhibitors Anagrelide is a phosphodiesterase 3 (PDE3) inhibitor. Avoid use of drug products with similar properties such as inotropes and other PDE3 inhibitors (e.g., cilostazol, milrinone) <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) and Clinical Pharmacology (12.2)]</span> .

7.3 Aspirin and Drugs that Increase Bleeding Risk Co-administration of single-dose or repeat-dose anagrelide and aspirin showed greater ex vivo anti-platelet aggregation effects than administration of aspirin alone <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3)]</span>. Results from an observational study in patients with essential thrombocythemia suggest the rate of major hemorrhagic events (MHEs) in patients treated with anagrelide is higher than in those subjects treated with another cytoreductive treatment. The majority of the major hemorrhagic events occurred in patients who were also receiving concomitant anti-aggregatory treatment (primarily, aspirin). Therefore, the potential risks of the concomitant use of anagrelide with aspirin should be assessed, particularly in patients with a high-risk profile for hemorrhage, before treatment is initiated <span class="opacity-50 text-xs">[see Warnings and Precautions (5.3)]</span> . Monitor patients for bleeding, particularly those receiving concomitant therapy with other drugs known to cause bleeding (e.g., anticoagulants, PDE3 inhibitors, NSAIDs, antiplatelet agents, selective serotonin reuptake inhibitors).

7.4 CYP450 Interactions CYP1A2 inhibitors: Anagrelide and its active metabolite are primarily metabolized by CYP1A2. Drugs that inhibit CYP1A2 (e.g., fluvoxamine, ciprofloxacin) could increase the exposure of anagrelide. Monitor patients for cardiovascular events and titrate doses accordingly when CYP1A2 inhibitors are co-administered. CYP1A2 inducers: CYP1A2 inducers could decrease the exposure of anagrelide. Patients taking concomitant CYP1A2 inducers (e.g., omeprazole) may need to have their dose titrated to compensate for the decrease in anagrelide exposure. CYP1A2 substrates: Anagrelide demonstrates limited inhibitory activity towards CYP1A2 in vitro and may alter the exposure of concomitant CYP1A2 substrates (e.g., theophylline, fluvoxamine, ondansetron).

None. None (4)

AND PRECAUTIONS Cardiovascular Toxicity: QT prolongation and ventricular tachycardia have been reported with anagrelide. Obtain a pre-treatment cardiovascular examination including an ECG in all patients. Monitor patients for cardiovascular effects. (5.1)

Pulmonary

Hypertension: Assess underlying cardiopulmonary disease prior to initiating therapy. (5.2)

Bleeding

Risk: Monitor patients for bleeding, including those receiving concomitant therapy with other drugs known to cause bleeding. (5.3)

5.1 Cardiovascular Toxicity Torsades de pointes and ventricular tachycardia have been reported with anagrelide. Obtain a pre-treatment cardiovascular examination including an ECG in all patients. During treatment with anagrelide monitor patients for cardiovascular effects and evaluate as necessary. Anagrelide increases the QTc interval of the electrocardiogram and increases the heart rate in healthy volunteers <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2)]</span> . Do not use anagrelide in patients with known risk factors for QT interval prolongation, such as congenital long QT syndrome, a known history of acquired QTc prolongation, medicinal products that can prolong QTc interval and hypokalemia <span class="opacity-50 text-xs">[see Drug Interactions (7.1)]</span> . Hepatic impairment increases anagrelide exposure and could increase the risk of QTc prolongation. Monitor patients with hepatic impairment for QTc prolongation and other cardiovascular adverse reactions. The potential risks and benefits of anagrelide therapy in a patient with mild and moderate hepatic impairment should be assessed before treatment is commenced. Reduce anagrelide dose in patients with moderate hepatic impairment. Avoid use of anagrelide in patients with severe hepatic impairment. In patients with heart failure, bradyarrhythmias, or electrolyte abnormalities, consider periodic monitoring with electrocardiograms <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.2)]</span> . Anagrelide is a phosphodiesterase 3 (PDE3) inhibitor and may cause vasodilation, tachycardia, palpitations, and congestive heart failure. Other drugs that inhibit PDE3 have caused decreased survival when compared with placebo in patients with Class III-IV congestive heart failure <span class="opacity-50 text-xs">[see Drug Interactions (7.2)]</span> . In patients with cardiac disease, use anagrelide only when the benefits outweigh the risks.

5.2 Pulmonary Hypertension Cases of pulmonary hypertension have been reported in patients treated with anagrelide. Evaluate patients for signs and symptoms of underlying cardiopulmonary disease prior to initiating and during anagrelide therapy <span class="opacity-50 text-xs">[see Adverse Reactions (6.1)]</span> .

5.3 Bleeding Risk Use of concomitant anagrelide and aspirin increased major hemorrhagic events in a postmarketing study. Assess the potential risks and benefits for concomitant use of anagrelide with aspirin, since bleeding risks may be increased. Monitor patients for bleeding, including those receiving concomitant therapy with other drugs known to cause bleeding (e.g., anticoagulants, PDE3 inhibitors, NSAIDs, antiplatelet agents, selective serotonin reuptake inhibitors) <span class="opacity-50 text-xs">[see Drug Interactions (7.3), Clinical Pharmacology (12.3)]</span> .

5.4 Pulmonary Toxicity Interstitial lung diseases (including allergic alveolitis, eosinophilic pneumonia and interstitial pneumonitis) have been reported to be associated with the use of anagrelide in post-marketing reports. Most cases presented with progressive dyspnea with lung infiltrations. The time of onset ranged from 1 week to several years after initiating anagrelide. If suspected, discontinue anagrelide and evaluate. Symptoms may improve after discontinuation <span class="opacity-50 text-xs">[see Adverse Reactions (6)]</span> .