Drug Interaction Report

MONITOR: Coadministration of daclizumab with other agents known to induce hepatotoxicity may increase the risk of liver injury. Serious drug-related hepatic injury, including liver failure and autoimmune hepatitis, has been reported across controlled and open-label studies in 1.7% of daclizumab-treated patients and may occur at any time during treatment and up to 5 months after treatment cessation. Fatal cases have occurred. In addition, cases of hepatic injury have occurred in patients taking daclizumab concomitantly with other hepatotoxic drugs; however, the contributory role of these other medicines has not been established.

MANAGEMENT: Caution is advised if daclizumab is used with other potentially hepatotoxic agents, including non-prescription products and herbal supplements. Patients treated with daclizumab should have serum transaminase levels and total bilirubin measured prior to initiation of treatment and monthly during treatment in accordance with the manufacturer's recommendations, and the dosing adjusted or interrupted as necessary. Patients should be advised to seek medical attention if they experience potential signs and symptoms of hepatotoxicity such as fever, rash, itching, anorexia, nausea, vomiting, fatigue, malaise, right upper quadrant pain, dark urine, pale stools, and jaundice.

MONITOR: Coadministration of daclizumab with other agents known to induce hepatotoxicity may increase the risk of liver injury. Serious drug-related hepatic injury, including liver failure and autoimmune hepatitis, has been reported across controlled and open-label studies in 1.7% of daclizumab-treated patients and may occur at any time during treatment and up to 5 months after treatment cessation. Fatal cases have occurred. In addition, cases of hepatic injury have occurred in patients taking daclizumab concomitantly with other hepatotoxic drugs; however, the contributory role of these other medicines has not been established.

MANAGEMENT: Caution is advised if daclizumab is used with other potentially hepatotoxic agents, including non-prescription products and herbal supplements. Patients treated with daclizumab should have serum transaminase levels and total bilirubin measured prior to initiation of treatment and monthly during treatment in accordance with the manufacturer's recommendations, and the dosing adjusted or interrupted as necessary. Patients should be advised to seek medical attention if they experience potential signs and symptoms of hepatotoxicity such as fever, rash, itching, anorexia, nausea, vomiting, fatigue, malaise, right upper quadrant pain, dark urine, pale stools, and jaundice.

MONITOR: Coadministration of daclizumab with other agents known to induce hepatotoxicity may increase the risk of liver injury. Serious drug-related hepatic injury, including liver failure and autoimmune hepatitis, has been reported across controlled and open-label studies in 1.7% of daclizumab-treated patients and may occur at any time during treatment and up to 5 months after treatment cessation. Fatal cases have occurred. In addition, cases of hepatic injury have occurred in patients taking daclizumab concomitantly with other hepatotoxic drugs; however, the contributory role of these other medicines has not been established.

MANAGEMENT: Caution is advised if daclizumab is used with other potentially hepatotoxic agents, including non-prescription products and herbal supplements. Patients treated with daclizumab should have serum transaminase levels and total bilirubin measured prior to initiation of treatment and monthly during treatment in accordance with the manufacturer's recommendations, and the dosing adjusted or interrupted as necessary. Patients should be advised to seek medical attention if they experience potential signs and symptoms of hepatotoxicity such as fever, rash, itching, anorexia, nausea, vomiting, fatigue, malaise, right upper quadrant pain, dark urine, pale stools, and jaundice.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of tezacaftor, deutivacaftor, and vanzacaftor. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation- dependent, and can vary widely among brands. Certain preparations of grapefruit juice (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. The risk and/or severity of serious side effects such as liver damage may be increased.

ADJUST DOSING INTERVAL: Administration with fat-containing food may increase the oral bioavailability of vanzacaftor and deutivacaftor. Administration with a fat containing meal increased vanzacaftor systemic exposure (AUC) by 4- (low-fat meal) to 6- (high-fat meal) fold. While deutivacaftor AUC increased approximately 3- (low-fat meal) to 4- (high-fat meal) fold, relative to administration in a fasting state. Tezacaftor exposure is not significantly affected by administration of fat-containing foods.

MANAGEMENT: Patients treated with tezacaftor, deutivacaftor, vanzacaftor -containing medications should avoid consumption of grapefruit juice and any food that contains grapefruit. To improve absorption, patients should be advised to take vanzacaftor and/or deutivacaftor containing medications with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products at approximately the same time of the day. A typical cystic fibrosis diet will satisfy this requirement.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of tezacaftor, deutivacaftor, and vanzacaftor. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation- dependent, and can vary widely among brands. Certain preparations of grapefruit juice (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. The risk and/or severity of serious side effects such as liver damage may be increased.

ADJUST DOSING INTERVAL: Administration with fat-containing food may increase the oral bioavailability of vanzacaftor and deutivacaftor. Administration with a fat containing meal increased vanzacaftor systemic exposure (AUC) by 4- (low-fat meal) to 6- (high-fat meal) fold. While deutivacaftor AUC increased approximately 3- (low-fat meal) to 4- (high-fat meal) fold, relative to administration in a fasting state. Tezacaftor exposure is not significantly affected by administration of fat-containing foods.

MANAGEMENT: Patients treated with tezacaftor, deutivacaftor, vanzacaftor -containing medications should avoid consumption of grapefruit juice and any food that contains grapefruit. To improve absorption, patients should be advised to take vanzacaftor and/or deutivacaftor containing medications with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products at approximately the same time of the day. A typical cystic fibrosis diet will satisfy this requirement.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of tezacaftor, deutivacaftor, and vanzacaftor. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In general, the effect of grapefruit juice is concentration-, dose- and preparation- dependent, and can vary widely among brands. Certain preparations of grapefruit juice (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. The risk and/or severity of serious side effects such as liver damage may be increased.

ADJUST DOSING INTERVAL: Administration with fat-containing food may increase the oral bioavailability of vanzacaftor and deutivacaftor. Administration with a fat containing meal increased vanzacaftor systemic exposure (AUC) by 4- (low-fat meal) to 6- (high-fat meal) fold. While deutivacaftor AUC increased approximately 3- (low-fat meal) to 4- (high-fat meal) fold, relative to administration in a fasting state. Tezacaftor exposure is not significantly affected by administration of fat-containing foods.

MANAGEMENT: Patients treated with tezacaftor, deutivacaftor, vanzacaftor -containing medications should avoid consumption of grapefruit juice and any food that contains grapefruit. To improve absorption, patients should be advised to take vanzacaftor and/or deutivacaftor containing medications with fat-containing foods such as eggs, avocados, nuts, meat, butter, peanut butter, cheese pizza, and whole-milk dairy products at approximately the same time of the day. A typical cystic fibrosis diet will satisfy this requirement.