Coadministration has not been studied but based on metabolism and clearance, as well as limited drug-drug interaction data, a clinically significant interaction is unlikely. Efavirenz is metabolized by CYP3A4 and CYP2B6. In vitro human microsomal studies and limited in vivo drug-drug interaction data indicate that albuvirtide has no inhibiting or inducing properties on P450 enzymes. Induction of CYP3A4 by efavirenz is unlikely to affect albuvirtide, a peptide which is eliminated by catabolism to its constituent amino acids.