Analysis of iron status after initiation of elexacaftor/tezacaftor/ivacaftor in people with cystic fibrosis.

BACKGROUND: Iron deficiency is highly prevalent in people with cystic fibrosis (PwCF). While elexacaftor/tezacaftor/ivacaftor (ETI) has shown remarkable improvements in respiratory symptoms in PwCF, the effect of ETI on iron status remains unknown. This study aims to identify the effect of ETI on iron status in PwCF. METHODS: A single-center retrospective cohort study of 127 adult PwCF was conducted to assess the impact of ETI on iron, ferritin, transferrin levels, and percent saturation of transferrin (PSAT). Data were collected from the electronic medical record from January 2017 to September 2022, encompassing 2 years before and after ETI initiation. The primary outcome was serum iron parameters: iron, ferritin, transferrin, and PSAT levels following ETI treatment. Secondary outcomes analyzed iron supplementation. Univariate and multivariate mixed-effects models were used for the analysis of ETI. RESULTS: After adjusting for covariates, following ETI initiation, the mean iron level increased by 20.24 µg/dL (p < .001), ferritin levels were 31.4% (p < .001) higher, PSAT showed a 5.09 percentage point increase (p < .001), and transferrin levels increased by 2.71 mg/dL (p = .439). Patients with and without iron supplementation experienced a significant increase in iron after ETI (p < .001). CONCLUSIONS: ETI is associated with a significant increase in iron, ferritin, and PSAT levels. Patients with and without iron supplementation demonstrated a significant increase in iron. This study shows the benefits of ETI on iron status in PwCF. However, further translational studies are required to understand the impact of ETI on iron absorption and metabolism in PwCF.

Real world study on elexacaftor-tezacaftor-ivacaftor impact on cholesterol levels in adults with cystic fibrosis.

INTRODUCTION: The introduction of the highly effective modulator therapy elexacaftor-tezacaftor-ivacaftor (ETI) has revolutionized the care of persons with cystic fibrosis (PwCF) with major improvements seen in lung function and body mass index. The effects of ETI therapy in real-world cohorts on other parameters such as cholesterol levels are largely unknown. METHODS: A single-center, retrospective chart review study was conducted to assess the change in lipid panels before and after ETI initiation. The study investigated total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels using both a univariate and multivariate mixed-effects model to evaluate the change after initiation of ETI in a cohort of PwCF. RESULTS: There were 128 adult PwCF included in the analysis. Statistically significant changes were seen in both univariate and multivariate analyses for TC, LDL-C, and HDL-C. On multivariate analysis, TC increased by an average of 15.0 mg/dL after ETI initiation (p < 0.0001), LDL-C increased by an average of 9.3 mg/dL (p < 0.001), and HDL-C increased by an average of 3.8 mg/dL (p < 0.001) after ETI initiation. CONCLUSION: In this real-world cohort of PwCF, cholesterol parameters increased after initiation with ETI therapy. Further consideration may need to be given for PwCF in regards to screening for cardiometabolic risk factors as PwCF age as well as the potential need for cholesterol-lowering therapies.

The Impact of CFTR Modulator Triple Therapy on Type 2 Inflammatory Response in Patients with Cystic Fibrosis.

Background Treatment of cystic fibrosis (CF) has been revolutionized by the use of cystic fibrosis transmembrane conductance regulator (CFTR) protein modulators such as elexacaftor/tezacaftor/ivacaftor (ETI) triple therapy. Prior studies support a role for type 2 (T2) inflammation in many people with CF (PwCF) and CF-asthma overlap syndrome (CFAOS) is considered a separate clinical entity. It is unknown whether initiation of ETI therapy impacts T2 inflammation in PwCF. We hypothesized that ETI initiation decreases T2 inflammation in PwCF. Methods A single center retrospective chart review was conducted for adult PwCF. As markers of T2 inflammation, absolute eosinophil count (AEC) and total immunoglobulin E (IgE) data were collected longitudinally 12 months prior to ETI therapy initiation and 12 months following therapy initiation. Multivariable analyses adjusted for the age, gender, CFTR mutation, disease severity, inhaled steroid use, and microbiological colonization. Results There was a statistically significant reduction (20.10%, p < 0.001) in 12-month mean IgE following ETI initiation; this change remained statistically significant in the multivariate model. The longitudinal analysis demonstrated no change in AEC following therapy initiation. Conclusion This study shows reduction in IgE but no change in AEC after ETI therapy initiation. We think that the lack of influence on AEC argues against an impact on previously established T2 inflammation and that the reduction in IgE is likely related to antigen load reduction post ETI. Further studies are warranted to determine the underlying mechanism of ETI impact on T2 inflammation and possible role for asthma immunomodulator therapy post ETI initiation in CFAOS.