Drug Interactions between givinostat and PC-CAP

GENERALLY AVOID: Alcohol may have additive CNS- and/or respiratory-depressant effects with propoxyphene. Misuse of propoxyphene, either alone or in combination with other CNS depressants, has been a major cause of drug-related deaths, particularly in patients with a history of emotional disturbances, suicidal ideation, or alcohol and drug abuse.

MANAGEMENT: The use of alcohol during propoxyphene therapy should be avoided. Patients should be warned not to exceed the recommended dosage of propoxyphene and to avoid activities requiring mental alertness until they know how these agents affect them.

ADJUST DOSING INTERVAL: Food increases the systemic exposure of givinostat. An open-label, randomized, crossover, single dose food effect study conducted in 12 healthy males used givinostat liquid filled capsules. Subjects received a single oral dose of givinostat (100 mg) in the fasting state or after a high-fat standard meal, with a washout period of at least 1 week in between. The high-fat standard meal resulted in an increase in systemic exposure (AUC) and maximum plasma concentration (Cmax) of about 40% and 23%, respectively, when compared to the fasted state. Additionally, the time to maximum concentration (Tmax) was delayed slightly from 2 to 3 hours.

MANAGEMENT: Givinostat should be administered with food to increase its absorption. In the case of the oral suspension, this can also help mask its bitter taste.

GENERALLY AVOID: The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss. The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

MANAGEMENT: Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.

The effect of grapefruit juice on the pharmacologic activity of caffeine is controversial. One report suggests that grapefruit juice increases the effect of caffeine. The proposed mechanism is inhibition of cytochrome P-450 metabolism of caffeine. However, a well-conducted pharmacokinetic/pharmacodynamic study did not demonstrate this effect. The clinical significance of this potential interaction is unknown.

One study has reported that coadministration of caffeine and aspirin lead to a 25% increase in the rate of appearance and 17% increase in maximum concentration of salicylate in the plasma. A significantly higher area under the plasma concentration time curve of salicylate was also reported when both drugs were administered together. The exact mechanism of this interaction has not been specified. Physicians and patients should be aware that coadministration of aspirin and caffeine may lead to higher salicylate levels faster.