vir is contraindicated, as elevated plasma concentrations of ribociclib may be associated with QT prolongation; exposure to tipranavir may also increase. Ribociclib is extensively metabolized by CYP3A4 and is a moderate CYP3A4 inhibitor; tipranavir is a strong CYP3A4 inhibitor and CYP3A4 substrate.
Tizanidine: (Major) Avoid coadministration of ribociclib with tizanidine due to an increased risk for QT prolongation. Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Tizanidine may also cause QT prolongation. Concomitant use may increase the risk for QT prolongation.
Tofacitinib: (Moderate) Use caution if coadministration of ribociclib with tofacitinib is necessary, as the systemic exposure of tofacitinib may be increased resulting in an increase in treatment-related adverse reactions; adjust the dose of tofacitinib if necessary. If the patient is also receiving a concomitant medication that results in strong CYP2C19 inhibition along with ribociclib (a moderate CYP3A4 inhibitor), reduce the dose of tofacitinib to 5 mg once daily. Ribociclib is a moderate CYP3A4 inhibitor and tofacitinib is a CYP3A4 substrate.
Tolterodine: (Major) Avoid coadministration of ribociclib with tolterodine due to an increased risk for QT prolongation. Systemic exposure of tolterodine may also be increased resulting in increase in treatment-related adverse reactions. Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Tolterodine has been associated with dose-dependent prolongation of the QT interval, especially in poor CYP2D6 metabolizers. Concomitant use may increase the risk for QT prolongation. Ribociclib is also a moderate CYP3A4 inhibitor and tolterodine is a CYP3A4 substrate.
Tolvaptan: (Major) Avoid coadministration of ribociclib with tolvaptan, as the systemic exposure of tolvaptan may be increased resulting in increase in treatment-related adverse reactions. Ribociclib is a moderate CYP3A4 inhibitor and tolvaptan is a CYP3A4 substrate.
Topiramate: (Moderate) Use caution if coadministration of ribociclib with topiramate is necessary, as the systemic exposure of ribociclib may decrease resulting in decreased efficacy. Ribociclib is extensively metabolized by CYP3A4 and topiramate is a weak CYP3A4 inducer.
Toremifene: (Major) Avoid coadministration of ribociclib with toremifene due to an increased risk for QT prolongation. Systemic exposure of toremifene may also be increased resulting in increase in treatment-related adverse reactions. Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Toremifene has also been shown to prolong the QTc interval in a dose- and concentration-related manner. Concomitant use may increase the risk for QT prolongation. Ribociclib is also a moderate CYP3A4 inhibitor and toremifene is a CYP3A4 substrate.
Trabectedin: (Moderate) Use caution if ribociclib is coadministered with trabectedin, as the systemic exposure of trabectedin may increase resulting in trabectedin-related adverse reactions. Ribociclib is a moderate CYP3A4 inhibitor and trabectedin is a CYP3A4 substrate.
Tramadol: (Moderate) Use caution with coadministration of ribociclib and tramadol, as the systemic exposure of tramadol may be increased resulting in an increase in treatment-related adverse reactions including seizures, sedation, and respiratory depression. Ribociclib is a moderate CYP3A4 inhibitor. Tramadol is p |
