Decreased plasma conc w/ strong CYP3A inducers eg, rifampicin, rifabutin, & St. John's wort; strong or moderate CYP3A inducers (carbamazepine, phenobarb, & phenytoin). Decreased efficacy w/ rifabutin & rifampin. Increased plasma conc w/ CYP3A inhibitors. Antagonized effect of ganciclovir & valganciclovir. Increased plasma conc of immunosuppressants (eg, tacrolimus, cyclosporin, everolimus, or sirolimus); HMG-CoA reductase inhibitors (eg, rosuvastatin); digoxin.