Drug Interaction Report

MONITOR: Concomitant use of multiple vasodilator drugs for the treatment of erectile dysfunction (ED) may increase the risk of additive adverse effects, including hypotension, dizziness, syncope, prolonged erection, or priapism. However, available data are conflicting. For example, approximately 4.9% and 7.1% of people in selected studies using single ingredient intracavernosal injections (ICIs) of papaverine reported experiencing painful/prolonged erections and priapism, respectively. Conversely, selected studies of people using ICIs containing papaverine and phentolamine reported an increase in the average rate of prolonged/painful erections to approximately 8.9%, but a reduction in the average rate of priapism to approximately 5.5%. Additionally, 1 case series reported an increase in dizziness and syncope when patients used both oral agents and ICIs to treat ED. Clinical data are not available for all possible combinations. The route of administration and amount of medication absorbed systemically may affect the clinical significance and severity of this interaction.

MANAGEMENT: Most clinical guidelines advise caution and closer clinical monitoring for patients on erectile dysfunction (ED) regimens that include multiple vasodilative agents due to the potential for additive adverse effects. Some drug manufacturers recommend avoiding combinations due to the potential risks and a lack of established data on safety. However, some of these medications are available as combinations (either commercially or via compounding) and some ED guidelines indicate that combination therapy may be appropriate in certain situations. Healthcare providers should refer to the product labeling and appropriate treatment guidelines for the most up to date information and recommendations; as well as, counsel patients on potential adverse effects and what to do should they occur.

MONITOR: It is uncertain whether asciminib causes clinically significant prolongation of the QT interval of the electrocardiogram. In clinical studies, prolongation of the Fridericia-corrected QT interval (QTcF) was reported in 3 of 356 (0.8%) of patients, with one report of QTcF greater than 500 msec together with more than 60 msec QTcF increase from baseline. Asciminib is not reported to prolong the corrected QT (QTc) interval by greater than 20 msec at the maximum recommended clinical dosage (200 mg twice daily); however, a prolongation of up to 10 msec cannot be excluded. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia, hypocalcemia). Moreover, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s).

MANAGEMENT: Some authorities recommend caution and clinical monitoring when asciminib is used with drugs that are known to cause QT interval prolongation. An ECG should be obtained at baseline and during treatment as clinically indicated, particularly in patients with a history of cardiac arrhythmias, uncontrolled or significant cardiac disease (including bradycardia), or congenital or family history of long QT syndrome. Serum electrolytes, including potassium and magnesium should also be corrected prior to starting asciminib therapy and monitored during treatment as clinically indicated. Patients should be advised to seek prompt medical attention if they experience symptoms that indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.

ADJUST DOSING INTERVAL: Food may reduce the oral bioavailability of asciminib. When a single 40 mg dose of asciminib was administered with a low-fat meal (400 calories; 25% fat) in healthy volunteers, asciminib peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 35% and 30%, respectively, compared to asciminib administered in the fasted state. Administration with a high-fat meal (1000 calories; 50% fat) decreased the Cmax and AUC of asciminib by 68% and 62%, respectively.

MANAGEMENT: To ensure adequate asciminib exposures, food consumption should be avoided for at least 2 hours before and 1 hour after taking asciminib.

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia. Patients should also avoid driving or operating hazardous machinery until they know how the medications affect them.

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia. Patients should also avoid driving or operating hazardous machinery until they know how the medications affect them.