Drug Interaction Report

MONITOR CLOSELY: The risk of rhabdomyolysis may be increased during coadministration of lenalidomide with HMG-CoA reductase inhibitors (statins). The mechanism is unknown but may involve additive pharmacodynamic effects. The European Medicines Agency Pharmacovigilance Risk Assessment Committee (PRAC) evaluated 23 cases of rhabdomyolysis associated with lenalidomide; concomitant use of statins occurred in 4 cases. All cases were considered serious and patients recovered after both drugs were discontinued. Rhabdomyolysis occurred within 5, 14 and 19 days after initiation of lenalidomide in 3 cases and within 8 days after increased lenalidomide dosage in the fourth case.

MANAGEMENT: European product labeling recommends caution and increased clinical and biological monitoring if lenalidomide is used in combination with statins, especially during the first several weeks of treatment. All patients treated with statins should be advised to promptly report any unexplained muscle pain, tenderness, or weakness, particularly if accompanied by malaise or fever.

MONITOR: Concomitant use of statin medication with substantial quantities of alcohol may increase the risk of hepatic injury. Transient increases in serum transaminases have been reported with statin use and while these increases generally resolve or improve with continued therapy or a brief interruption in therapy, there have been rare postmarketing reports of fatal and non-fatal hepatic failure in patients taking statins. Patients who consume substantial quantities of alcohol and/or have a history of liver disease may be at increased risk for hepatic injury. Active liver disease or unexplained transaminase elevations are contraindications to statin use.

MANAGEMENT: Patients should be counseled to avoid substantial quantities of alcohol in combination with statin medications and clinicians should be aware of the increased risk for hepatotoxicity in these patients.