Glucuronidation of elvitegravir is facilitated by the enzymes UGT1A1 and 3, resulting in increased blood plasma levels when taken together with strong UGT1A inhibitors such as ritonavir and other HIV protease inhibitors [REF].
Furthermore, elvitegravir is a weak to medium inducer of CYP1A2, CYP2C19, CYP2C9, CYP3A, and a number of UGTs; the clinical relevance of these findings is however unclear [REF].