Coadministration has not been studied but based on metabolism and clearance a pharmacokinetic interaction is unlikely. Granisetron is metabolized by CYP3A4. Cabotegravir was shown to have no impact on midazolam (a sensitive CYP3A4 substrate) in healthy volunteers. Likewise, rilpivirine does not inibit or induce CYP3A4. Rilpivirine has been associated with prolongation of the QTc interval at supra-therapeutic doses but these are unlikely to occur when coadministered with granisetron. However, the product label for rilpivirine indicates that rilpivirine should be used with caution in combination with drugs with a known risk of Torsade de Pointes. Granisetron has a possible risk of QT prolongation and/or TdP on the CredibleMeds.org website.