Drug Interactions between erlotinib and nintedanib

GENERALLY AVOID: Grapefruit and grapefruit juice may increase the plasma concentrations of erlotinib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Inhibition of hepatic CYP450 3A4 may also contribute. The interaction has not been studied with grapefruit juice, but has been reported for ketoconazole, a potent CYP450 3A4 inhibitor that increased erlotinib systemic exposure (AUC) by 67%. In general, the effects of grapefruit products are concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition.

GENERALLY AVOID: Cigarette smoking reduces erlotinib exposure due to induction of hepatic CYP450 1A2, one of the isoenzymes responsible for the metabolic clearance of erlotinib. Induction of CYP450 1A1 in the lungs may also contribute. In one pharmacokinetic study of healthy subjects given a single 150 mg dose of erlotinib, mean erlotinib peak plasma concentration (Cmax), systemic exposure (AUC) and plasma concentration at 24 hours were decreased by 35%, 64% and 88%, respectively, in current smokers compared to former/never smokers. Likewise, in a phase 3 non-small cell lung cancer (NSCLC) trial, the steady-state trough plasma concentrations of erlotinib in current smokers were approximately 2-fold less than in former/never smokers, accompanied by a 24% increase in apparent erlotinib plasma clearance. In a phase 1 dose-escalation study that analyzed the steady-state pharmacokinetics of erlotinib in current smokers with NSCLC, there was a dose-proportional increase in erlotinib exposure when the dose was increased from 150 mg to 300 mg, the maximum tolerated dose in the study population. Median steady-state trough plasma concentration at the 300 mg dose was approximately 3-fold higher than at the 150 mg dose. The clinical impact of smoking on erlotinib efficacy has not been studied.

ADJUST DOSING INTERVAL: Food enhances the oral absorption of erlotinib. According to the product labeling, administration with food increased the oral bioavailability of erlotinib from approximately 60% to almost 100% compared to administration in the fasting state.

MANAGEMENT: Consumption of grapefruit and grapefruit juice should be avoided or limited during treatment with erlotinib. Patients who currently smoke cigarettes are advised to stop smoking as soon as possible. If cigarette smoking is continued while taking erlotinib, the manufacturer recommends increasing the dosage of erlotinib by 50 mg increments at 2-week intervals up to a maximum of 300 mg as tolerated. However, the efficacy and long-term safety of dosages higher than 150 mg daily have not been established. Data from a double-blind, randomized phase 3 study (MO22162, CURRENTS) demonstrated no benefit in progression free survival or overall survival with an erlotinib dosage of 300 mg daily relative to the recommended dosage of 150 mg daily in active smokers (average of 38 pack years) with locally advanced or metastatic NSCLC who have failed chemotherapy, although patients in the study were not selected based on epidermal growth factor receptor (EGFR) mutation status. Safety data were comparable between the two dosages, but a numerical increase in the incidence of rash, interstitial lung disease and diarrhea was observed with the higher dosage. Patients who have received a dosage increase should immediately revert to the recommended dosage of 150 mg or 100 mg once daily (depending on indication) upon cessation of smoking. Erlotinib should be administered on an empty stomach at least one hour before or two hours after the ingestion of food.

ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of nintedanib. After food intake, nintedanib exposure increased by approximately 20% compared to administration under fasted conditions. Absorption was also delayed, as indicated by an increase in the median time to reach maximum plasma concentration (Tmax) from 2 hours in the fasted state to approximately 4 hours under fed conditions, irrespective of the type of food ingested. In an in vitro study, mixing nintedanib capsules with a small amount of apple sauce or chocolate pudding for up to 15 minutes did not have any impact on their pharmaceutical quality, but swelling and deformation of the capsules were observed with longer exposure time due to water uptake of the gelatin capsule shell. Therefore, administration with soft food would not be expected to alter the clinical effect of nintedanib when taken immediately.

GENERALLY AVOID: Grapefruit and grapefruit juice may increase the plasma concentrations of nintedanib, which has been shown to be a substrate of the P-glycoprotein (P-gp) efflux transporter and a minor substrate of the CYP450 3A4 isoenzyme. The proposed mechanism is inhibition of both P-gp-mediated efflux in the gut wall as well as CYP450 3A4-mediated first-pass metabolism in the intestinal tract by certain compounds present in grapefruit.

MANAGEMENT: Nintedanib should be administered with food to reduce the incidence of gastrointestinal effects. Nintedanib capsules may be taken with water or a small amount (teaspoonful) of cold or room temperature soft food, such as apple sauce or chocolate pudding, and must be swallowed whole (unchewed) immediately, to ensure the capsule stays intact. Food containing grapefruit, grapefruit juice, Seville orange (a citrus relative of the grapefruit), or Seville orange juice should be avoided during treatment with nintedanib.