Drug Interactions between upadacitinib and vadadustat

GENERALLY AVOID: Grapefruit, grapefruit juice or supplements containing grapefruit may increase the plasma concentrations of upadacitinib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in these fruits. Inhibition of hepatic CYP450 3A4 may also contribute. The interaction has not been studied with grapefruit. In study subjects, administration with the potent CYP450 3A4 inhibitor ketoconazole increased upadacitinib peak plasma concentration (Cmax) and systemic exposure (AUC) by 70% and 75%, respectively. 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. Upadacitinib side effects including lymphopenia, neutropenia, anemia, serious infections, and hyperlipidemia may be increased.

MONITOR CLOSELY: Smoking during treatment with upadacitinib may increase the risk of major adverse cardiovascular events (MACE) and the risk of developing malignancies. During upadacitinib clinical studies, current or past smokers had an additional increased risk of overall malignancies. Also, upadacitinib may increase patients' risk of MACE, including myocardial infarction, stroke, and cardiovascular death.

MANAGEMENT: The manufacturer advises that concomitant use of upadacitinib with grapefruit, grapefruit juice, or supplements containing grapefruit should be avoided. Caution is advised if upadacitinib is prescribed to current or past smokers. Patients should be informed about the symptoms of serious cardiovascular events and the steps to take if they occur. The manufacturer recommends discontinuing upadacitinib in patients who have experienced a myocardial infarction or stroke.

MONITOR: Smoking and alcohol consumption during therapy with vadadustat may increase the risk of gastrointestinal erosions. Serious erosions, including gastrointestinal bleeding and the need for red blood cell transfusions, have been reported during vadadustat clinical trials. Patients with a history of gastrointestinal erosion, peptic ulcer disease, and current tobacco smokers and alcohol drinkers may be at higher risk of gastrointestinal injury.

MANAGEMENT: Caution is advised if vadadustat is prescribed to current tobacco smokers or alcohol drinkers. Patients should be advised to contact their physician if they develop potential signs and symptoms of gastrointestinal injury such as abdominal pain, hematemesis, trouble swallowing, chest or throat pain, and/or black, tarry stools.