Drug Interactions between pexidartinib and Symfi Lo

GENERALLY AVOID: Serious cases of hepatotoxicity, some fatal, have occurred in patients treated with pexidartinib. Concomitant use of other potentially hepatotoxic agents may potentiate the risk of liver injury. The mechanism of hepatotoxicity is unknown, its occurrence cannot be predicted, and it is unknown whether liver injury occurs in the absence of increased transaminases. In one study, 5% of patients who received pexidartinib developed signs of serious liver injury (elevated serum transaminases greater than 3 times the upper limit of normal (ULN) and total bilirubin greater than 2 times ULN). In these patients, peak ALT ranged from 6 to 9 times ULN, peak total bilirubin ranged from 2.5 to 15 times ULN, and ALP was greater than 2 times ULN. Liver transaminases and total bilirubin improved to less than 2 times ULN in these patients 1 to 7 months after discontinuing pexidartinib.

MANAGEMENT: The use of pexidartinib with other potentially hepatotoxic agents should be avoided. Patients treated with pexidartinib should have liver function tests, including AST, ALT, total bilirubin, direct bilirubin, ALP, and gamma-glutamyl transferase (GGT), prior to initiation of pexidartinib, weekly for the first 8 weeks, every 2 weeks for the next month, and every 3 months thereafter. Pexidartinib therapy may require a dosage reduction, to be withheld, or permanently discontinued based on the severity of the hepatotoxicity. A recurrence of increased serum transaminases, bilirubin, or ALP may occur upon rechallenge with a reduced dose of pexidartinib. Liver function tests should be performed weekly for the first month after rechallenge. 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: Serious cases of hepatotoxicity, some fatal, have occurred in patients treated with pexidartinib. Concomitant use of other potentially hepatotoxic agents may potentiate the risk of liver injury. The mechanism of hepatotoxicity is unknown, its occurrence cannot be predicted, and it is unknown whether liver injury occurs in the absence of increased transaminases. In one study, 5% of patients who received pexidartinib developed signs of serious liver injury (elevated serum transaminases greater than 3 times the upper limit of normal (ULN) and total bilirubin greater than 2 times ULN). In these patients, peak ALT ranged from 6 to 9 times ULN, peak total bilirubin ranged from 2.5 to 15 times ULN, and ALP was greater than 2 times ULN. Liver transaminases and total bilirubin improved to less than 2 times ULN in these patients 1 to 7 months after discontinuing pexidartinib.

MANAGEMENT: The use of pexidartinib with other potentially hepatotoxic agents should be avoided. Patients treated with pexidartinib should have liver function tests, including AST, ALT, total bilirubin, direct bilirubin, ALP, and gamma-glutamyl transferase (GGT), prior to initiation of pexidartinib, weekly for the first 8 weeks, every 2 weeks for the next month, and every 3 months thereafter. Pexidartinib therapy may require a dosage reduction, to be withheld, or permanently discontinued based on the severity of the hepatotoxicity. A recurrence of increased serum transaminases, bilirubin, or ALP may occur upon rechallenge with a reduced dose of pexidartinib. Liver function tests should be performed weekly for the first month after rechallenge. 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: Serious cases of hepatotoxicity, some fatal, have occurred in patients treated with pexidartinib. Concomitant use of other potentially hepatotoxic agents may potentiate the risk of liver injury. The mechanism of hepatotoxicity is unknown, its occurrence cannot be predicted, and it is unknown whether liver injury occurs in the absence of increased transaminases. In one study, 5% of patients who received pexidartinib developed signs of serious liver injury (elevated serum transaminases greater than 3 times the upper limit of normal (ULN) and total bilirubin greater than 2 times ULN). In these patients, peak ALT ranged from 6 to 9 times ULN, peak total bilirubin ranged from 2.5 to 15 times ULN, and ALP was greater than 2 times ULN. Liver transaminases and total bilirubin improved to less than 2 times ULN in these patients 1 to 7 months after discontinuing pexidartinib.

MANAGEMENT: The use of pexidartinib with other potentially hepatotoxic agents should be avoided. Patients treated with pexidartinib should have liver function tests, including AST, ALT, total bilirubin, direct bilirubin, ALP, and gamma-glutamyl transferase (GGT), prior to initiation of pexidartinib, weekly for the first 8 weeks, every 2 weeks for the next month, and every 3 months thereafter. Pexidartinib therapy may require a dosage reduction, to be withheld, or permanently discontinued based on the severity of the hepatotoxicity. A recurrence of increased serum transaminases, bilirubin, or ALP may occur upon rechallenge with a reduced dose of pexidartinib. Liver function tests should be performed weekly for the first month after rechallenge. 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 efavirenz with other agents known to induce hepatotoxicity may potentiate the risk of liver injury. Efavirenz has been associated with hepatotoxicity during postmarketing use. Among reported cases of hepatic failure, a few occurred in patients with no preexisting hepatic disease or other identifiable risk factors.

MANAGEMENT: The risk of hepatic injury should be considered when efavirenz is used in combination with other agents that are potentially hepatotoxic (e.g., acetaminophen; alcohol; androgens and anabolic steroids; antituberculous agents; azole antifungal agents; ACE inhibitors; cyclosporine (high dosages); disulfiram; endothelin receptor antagonists; interferons; ketolide and macrolide antibiotics; kinase inhibitors; minocycline; nonsteroidal anti-inflammatory agents; other HIV reverse transcriptase inhibitors; proteasome inhibitors; retinoids; sulfonamides; tamoxifen; thiazolidinediones; tolvaptan; vincristine; zileuton; anticonvulsants such as carbamazepine, hydantoins, felbamate, and valproic acid; lipid-lowering medications such as fenofibrate, lomitapide, mipomersen, niacin, and statins; herbals and nutritional supplements such as black cohosh, chaparral, comfrey, DHEA, kava, pennyroyal oil, and red yeast rice). 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. Monitoring of liver function tests should occur before and during treatment, especially in patients with underlying hepatic disease (including hepatitis B or C coinfection) or marked transaminase elevations. The benefit of continued therapy with efavirenz should be considered against the unknown risks of significant liver toxicity in patients who develop persistent elevations of serum transaminases greater than five times the upper limit of normal.

MONITOR: Coadministration of efavirenz with other agents known to induce hepatotoxicity may potentiate the risk of liver injury. Efavirenz has been associated with hepatotoxicity during postmarketing use. Among reported cases of hepatic failure, a few occurred in patients with no preexisting hepatic disease or other identifiable risk factors.

MANAGEMENT: The risk of hepatic injury should be considered when efavirenz is used in combination with other agents that are potentially hepatotoxic (e.g., acetaminophen; alcohol; androgens and anabolic steroids; antituberculous agents; azole antifungal agents; ACE inhibitors; cyclosporine (high dosages); disulfiram; endothelin receptor antagonists; interferons; ketolide and macrolide antibiotics; kinase inhibitors; minocycline; nonsteroidal anti-inflammatory agents; other HIV reverse transcriptase inhibitors; proteasome inhibitors; retinoids; sulfonamides; tamoxifen; thiazolidinediones; tolvaptan; vincristine; zileuton; anticonvulsants such as carbamazepine, hydantoins, felbamate, and valproic acid; lipid-lowering medications such as fenofibrate, lomitapide, mipomersen, niacin, and statins; herbals and nutritional supplements such as black cohosh, chaparral, comfrey, DHEA, kava, pennyroyal oil, and red yeast rice). 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. Monitoring of liver function tests should occur before and during treatment, especially in patients with underlying hepatic disease (including hepatitis B or C coinfection) or marked transaminase elevations. The benefit of continued therapy with efavirenz should be considered against the unknown risks of significant liver toxicity in patients who develop persistent elevations of serum transaminases greater than five times the upper limit of normal.