use pirfenidone over nintedanib for less CYP interactions for pulmonary fibrosis

Nintedanib reacts with CYP450 enzymes whereas Pirfenidone does not.

Source

While currently there is no cure for idiopathic pulmonary fibrosis, the antifibrotic agents nintedanib and pirfenidone both slow disease progression, decrease the rate of exacerbations, and appear to positively impact mortality. Current efficacy data do not clearly favor one agent over the other, and an agent is chosen based on availability, cost, drug interactions, and adverse event profiles. In this patient, pirfenidone is the preferred agent because it does not have a drug interaction with strong inducers of cytochrome P450 family 3 subfamily A member 4 (CYP3A4), including phenytoin (choice A is correct). Nintedanib is a substrate of P-glycoprotein and is metabolized by CYP3A4. Consequently, concomitant use of strong CYP3A4 inducers (eg, carbamazepine, phenytoin, and St. John's wort) with nintedanib should be avoided because these drugs decrease concentrations of nintedanib and may impair its effectiveness.

Allergic reactions are uncommon with both nintedanib and pirfenidone, and neither exhibits allergic cross-reactivity with sulfonamides (choice D is incorrect). Neither medication requires dose modification in renal insufficiency (choice B is incorrect), and neither medication significantly interferes with glycemic control or interacts with common antidiabetic medications (choice C is incorrect).1

Footnotes

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