Drug Interaction Report

MONITOR: Coadministration with rucaparib may increase the plasma concentrations and the risk of adverse effects of drugs that are substrates of CYP450 2C9. The proposed mechanism is decreased clearance due to rucaparib-mediated inhibition of CYP450 2C9. In a clinical study, rucaparib increased S-warfarin Cmax and AUC by 1.05- and 1.49-fold, respectively.

MANAGEMENT: Caution is advised if rucaparib is used concomitantly with drugs that are substrates of CYP450 2C9, particularly those with a narrow therapeutic range. Dosage adjustments as well as clinical and laboratory monitoring should be considered whenever rucaparib is added to or withdrawn from therapy with these drugs. Patients should be monitored for the development of adverse effects.

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.