omitant use of strong CYP3A inhibitors during treatment with Zykadia. If it is not possible to avoid concomitant use with strong CYP3A inhibitors (including, but not limited to, ritonavir, saquinavir, telithromycin, ketoconazole, itraconazole, voriconazole, posaconazole and nefazodone), reduce the ceritinib dose by approximately one third, rounded to the nearest multiple of the 150 mg dosage strength. After discontinuation of a strong CYP3A inhibitor, resume the ceritinib dose that was taken prior to initiating the strong CYP3A inhibitor.
P-gp inhibitors
Based on in vitro data, ceritinib is a substrate of the efflux transporter P-glycoprotein (P-gp). If ceritinib is administered with medicinal products that inhibit P-gp, an increase in ceritinib concentration is likely. Caution should be exercised with concomitant use of P-gp inhibitors and ADRs carefully monitored.
Agents that may decrease ceritinib plasma concentrations
Strong CYP3A and P-gp inducers
In healthy subjects, co-administration of a single 750 mg fasted ceritinib dose with rifampicin (600 mg daily for 14 days), a strong CYP3A/P-gp inducer, resulted in 70% and 44% decreases in ceritinib AUCinf and Cmax, respectively, compared to when ceritinib was given alone. Co-administration of ceritinib with strong CYP3A/P-gp inducers decreases ceritinib plasma concentrations. Concomitant use of strong CYP3A inducers should be avoided; this includes, but is not limited to, carbamazepine, phenobarbital, phenytoin, rifabutin, rifampicin and St. John's Wort (Hypericum perforatum). Caution should be exercised with concomitant use of P-gp inducers.
Agents that affect gastric pH
Ceritinib demonstrates pH-dependent solubility and becomes poorly soluble as pH increases in vitro. Acid reducing agents (e.g., proton pump inhibitors, H2-receptor antagonists, antacids) can alter the solubility of ceritinib and reduce its bioavailability. Co-administration of a single 750 mg fasted ceritinib dose with a proton pump inhibitor (esomeprazole) 40 mg daily for 6 days in healthy, fasting subjects decreased ceritinib AUC by 76% and Cmax by 79%. The drug-drug interaction study was designed to observe the impact of proton pump inhibitor in the worst scenario, but in clinical use the impact of proton pump inhibitor on ceritinib exposure appears to be less pronounced. A dedicated study to eva luate the effect of gastric acid-reducing agents on the bioavailability of ceritinib under steady state has not been conducted. Caution is advised with concomitant use of proton pump inhibitors, as exposure of ceritinib may be reduced. There is no data with concomitant use of H2 blockers or antacids. However, the risk for a clinically relevant decrease in bioavailability of ceritinib is possibly lower with concomitant use of H2 blockers if they are administered 10 hours before or 2 hours after the ceritinib dose, and with antacids if they are administered 2 hours before or 2 hours after the ceritinib dose.
Agents whose plasma concentration may be altered by ceritinib
CYP3A and CYP2C9 substrates
Based on in vitro data, ceritinib competitively inhibits the metabolism of a CYP3A substrate, midazolam, and a CYP2C9 substrate, diclofenac. Time-dependent inhibition of CYP3A was also observed.
Ceritinib has been classified in vivo as a strong CYP3A4 inhibitor and has the potential to interact with medicinal products that are metabolised by CYP3A, which may lead to increased serum concentrations of the other pro |
