Elexacaftor/tezacaftor/ivacaftor prescription in lung transplant recipients with cystic fibrosis in the US.

Background: Elexacaftor/tezacaftor/ivacaftor (ETI) has dramatically improved pulmonary and extrapulmonary manifestations of cystic fibrosis (CF). ETI clinical trials excluded lung transplant (LTx) recipients and current post-transplant prescribing practices are not evidence-based. We sought to identify the prevalence of new ETI prescriptions among CF LTx recipients in the United States (U.S.) and factors associated with ETI prescription after LTx.

Methods: We performed a retrospective cross-sectional study of LTx recipients through December 2022 using the Cystic Fibrosis Foundation Patient Registry. Recipients were alive as of October 2019, had an ETI-eligible genotype, and were not prescribed ETI before LTx. Logistic regression was used to assess factors associated with ETI prescription. CF Center prescribing patterns were categorized based on the proportion of LTx recipients who were prescribed ETI after LTx at each center.

Results: Overall, 488/1666 (29.3 %) of patients were prescribed ETI after LTx. The presence of sinus disease (OR 2.12, 95 % CI 1.51-2.99) and BMI<18.5 kg/m² (OR 1.52, 95 % CI 1.13-2.04) were positively associated with ETI prescription after LTx. CF center prescribing pattern ["middle prescribing": OR 0.19, 95 % CI 0.14-0.26; "low prescribing": OR 0.02, 95 % CI 0.01-0.04; "high prescribing": reference group] and zero F508del alleles (OR 0.18, 95 % CI 0.07-0.49; 1 or 2 alleles: reference group) were negatively associated with ETI prescription after LTx.

Conclusions: ETI was newly prescribed to almost 30 % of eligible LTx recipients in the U.S. Even when including patient clinical characteristics in the model, CF center prescribing pattern was one of the strongest factors associated with ETI prescription after LTx.