Therapeutic drug monitoring of elexacaftor, tezacaftor, and ivacaftor before, during, and after pregnancy in women with cystic fibrosis: An observational study.

Background: Elexacaftor/tezacaftor/ivacaftor (ETI) has improved health and increased life expectancy in many patients with cystic fibrosis (pwCF). Family planning issues have become more important since then. Many women decide to remain on modulator therapy during pregnancy despite insufficient evidence-based recommendations for continuing ETI during pregnancy and lactation.

Therapeutic Drug Monitoring of Elexacaftor, Tezacaftor, and Ivacaftor in Adult People with Cystic Fibrosis.

Background/objectives: Elexacaftor, tezacaftor, and ivacaftor (ETI) have significantly improved lung function in people with cystic fibrosis (pwCF). Despite exceptional improvements in most cases, treatment-related inter-subject variability and drug-drug interactions that complicate modulator therapy have been reported.

Methods: This retrospective analysis presents data on the serum concentration of ETI in our pwCF with full or reduced dosage from August 2021 to December 2023 via routine therapeutic drug monitoring (TDM).