Drug Interactions between Addaprin and entecavir

MONITOR: Because entecavir is primarily eliminated by renal excretion, coadministration with drugs that affect renal function may alter the plasma concentrations of entecavir and/or the coadministered drug. In patients with renal impairment, the apparent oral clearance of entecavir has been shown to decrease as the creatinine clearance decreases. In a small pilot study consisting of nine liver transplant recipients on a stable dose of cyclosporine or tacrolimus, entecavir exposure was approximately 2-fold that in healthy subjects with normal renal function. Altered renal function contributed to the increase in entecavir exposure in these patients.

MANAGEMENT: Caution is advised if entecavir is prescribed in combination with potentially nephrotoxic drugs (e.g., aminoglycosides; polypeptide, glycopeptide, and polymyxin antibiotics; amphotericin B; adefovir; cidofovir; tenofovir; foscarnet; cisplatin; deferasirox; gallium nitrate; lithium; mesalamine; certain immunosuppressants; intravenous bisphosphonates; intravenous pentamidine; high intravenous dosages of methotrexate; high dosages and/or chronic use of nonsteroidal anti-inflammatory agents). Renal function should be evaluated prior to and during therapy with entecavir. Dosage adjustment is required in patients with renal insufficiency (creatinine clearance below 50 mL/min) at baseline or during treatment in accordance with the manufacturer's product labeling.