Drug General Information (ID: DDIKP318FB)
Drug Name			Efavirenz		Drug Info		Glasdegib		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anti-Hiv Agents				Antineoplastics/Hedgehog Pathway Inhibitors
Structure

Mechanism of Efavirenz-Glasdegib Interaction (Severity Level: Major)
Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Drug Name		Efavirenz				Glasdegib
Mechanism		Prolong QT interval				Prolong QT interval
Key Mechanism Factor 1
		Factor Name		QT interval
		Factor Description		Long QT syndrome is a heart signaling disorder that can cause a fast, chaotic heartbeat (arrhythmia). Many people may not exhibit symptoms, and usually the condition is detected during routine medical tests. In others, the most common symptoms include: sudden fainting, palpitations, dizziness, seizures, sudden death.
Mechanism Description		Increased risk of prolong QT interval by the combination of Efavirenz and Glasdegib

Recommended Action
Management		Coadministration of glasdegib with efavirenz should generally be avoided. Consider alternatives to efavirenz. Caution and clinical monitoring are recommended if concomitant use is required. Patients should have electrocardiograms (ECGs) performed prior to initiation of treatment with glasdegib, approximately one week after initiation, and then once monthly for the next two months, although patients with risk factors may require more frequent and ongoing ECG monitoring. If QTc interval is greater than 500 msec at any time during treatment, interrupt and reduce glasdegib dosing in accordance with product labeling recommendations. Glasdegib should be permanently discontinued in patients who develop QTc interval prolongation with signs or symptoms of life-threatening arrhythmia. Because hypokalemia and hypomagnesemia are risk factors for ventricular arrhythmias, electrolyte levels should also be obtained prior to and during treatment, and any abnormalities corrected as necessary.

References
1	Product Information. Daurismo (glasdegib). Pfizer U.S. Pharmaceuticals Group, New York, NY.
2	Product Information. Sustiva (efavirenz). DuPont Pharmaceuticals, Wilmington, DE.