Real-world safety and effectiveness of elexacaftor/tezacaftor/ivacaftor in people with cystic fibrosis: Interim results of a long-term registry-based study

Cystic fibrosis liver disease in the new era of cystic fibrosis transmembrane conductance regulator (CFTR) modulators

Cystic fibrosis liver disease (CFLD) is characterised by a wide heterogenity of manifestations and severity. It represents a major cause of morbidity in people with cystic fibrosis (PwCF), which will be of increasing relevance as survival increases in the new era of cystic fibrosis care. No medical therapy currently available has evidence to treat or prevent progression of liver disease. Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulators may be transformative on pulmonary, nutritional and quality of life, but direct effect on long term liver disease outcomes is not yet established. Drug-associated hepatic adverse effects may be common, and clinician familiarity with drug-monitoring recommendations is essential. Longitudinal studies are required to understand the effect of CFTR modulators on the incidence and natural history of CFLD, including with early treatment initiation, in established advanced liver disease, and post liver transplantation.

CFTR dysfunction leads to defective bacterial eradication on cystic fibrosis airways

Dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel by genetic mutations causes the inherited disease cystic fibrosis (CF). CF lung disease that involves multiple disorders of epithelial function likely results from loss of CFTR function as an anion channel conducting chloride and bicarbonate ions and its function as a cellular regulator modulating the activity of membrane and cytosol proteins. In the absence of CFTR activity, abundant mucus accumulation, bacterial infection and inflammation characterize CF airways, in which inflammation-associated tissue remodeling and damage gradually destroys the lung. Deciphering the link between CFTR dysfunction and bacterial infection in CF airways may reveal the pathogenesis of CF lung disease and guide the development of new treatments. Research efforts towards this goal, including high salt, low volume, airway surface liquid acidosis and abnormal mucus hypotheses are critically reviewed.

Real-world effectiveness of elexacaftor/tezacaftor/ivacaftor on the burden of illness in adolescents and adults with cystic fibrosis

Background

Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) has been shown to be safe and efficacious in people with cystic fibrosis (CF) aged ≥2 years. Here, we describe results from an observational study assessing change in burden of illness following initiating ELX/TEZ/IVA in real-world settings.

Methods

This US-based, multicenter, observational study used data from electronic medical records to evaluate real-world burden of illness before and after ELX/TEZ/IVA initiation in people with CF aged ≥12 years heterozygous for F508del and a minimal function mutation (F/MF) or an uncharacterized CFTR mutation. Endpoints included absolute change from baseline in percent predicted forced expiratory volume in 1 s (ppFEV1), body mass index (BMI) and BMI-for-age z-score, glycated hemoglobin (HbA1c), and numbers of pulmonary exacerbations (PEx).

Results

Overall, 206 people with CF were enrolled (mean [SD] age 22.5 [11.1] years; 192 [93.2%] with F/MF genotype). Mean follow-up was 15.6 (SD, 1.6) months. Improvements in ppFEV1 (7.3 [95% CI: 5.7, 8.8] percentage points) were observed from baseline through follow-up. Increases in BMI (1.40 [95% CI: 1.07, 1.77] kg/m2) and BMI-for-age z-score (0.14 [95% CI: 0.00, 0.28]) were also observed from baseline at 12 months. The estimated annualized rate of any PEx was 1.31 at baseline and 0.61 over follow-up (rate ratio 0.47 [95% CI: 0.39, 0.55]), with annualized rates of PEx requiring antibiotics and hospitalizations of 0.55 and 0.88 in the baseline period and 0.12 and 0.36 over follow-up (rate ratios 0.22 [95% CI: 0.15, 0.31] and 0.41 [95% CI: 0.32, 0.51]), respectively. Absolute change in HbA1c was -0.22 (95% CI: -0.38, -0.06) from baseline through follow-up.

Conclusions

ELX/TEZ/IVA treatment was associated with improved lung function, increased BMI, reduced frequency of PEx, and improved (i.e., reduced) HbA1c. These results confirm the broad clinical benefits of ELX/TEZ/IVA seen in clinical trials and show the potential for ELX/TEZ/IVA to improve markers of glucose metabolism.

Year in review 2023 - Back to the future

This review synthesizes articles published in 2023, focusing on the impact of elexacaftor-tezacaftor-ivacaftor (ETI) in cystic fibrosis (CF) care. Real-world data highlights sustained benefits of ETI across age groups, while challenges like neuropsychological side effects persist. Beyond CFTR modulators, research explores telemedicine and novel therapies. Prioritizing equitable access and addressing unmet needs remain crucial for comprehensive CF management.

Standards for the care of people with cystic fibrosis (CF); recognising and addressing CF health issues

This is the third in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on recognising and addressing CF health issues. The guidance was produced with wide stakeholder engagement, including people from the CF community, using an evidence-based framework. Authors contributed sections, and summary statements which were reviewed by a Delphi consultation. Monitoring and treating airway infection, inflammation and pulmonary exacerbations remains important, despite the widespread availability of CFTR modulators and their accompanying health improvements. Extrapulmonary CF-specific health issues persist, such as diabetes, liver disease, bone disease, stones and other renal issues, and intestinal obstruction. These health issues require multidisciplinary care with input from the relevant specialists. Cancer is more common in people with CF compared to the general population, and requires regular screening. The CF life journey requires mental and emotional adaptation to psychosocial and physical challenges, with support from the CF team and the CF psychologist. This is particularly important when life gets challenging, with disease progression requiring increased treatments, breathing support and potentially transplantation. Planning for end of life remains a necessary aspect of care and should be discussed openly, honestly, with sensitivity and compassion for the person with CF and their family. CF teams should proactively recognise and address CF-specific health issues, and support mental and emotional wellbeing while accompanying people with CF and their families on their life journey.

Cystic fibrosis in Europe: improved lung function and longevity - reasons for cautious optimism, but challenges remain

BACKGROUND

Prognosis and disease severity in cystic fibrosis (CF) are linked to declining lung function. To characterise lung function by the number of adults in countries with different levels of Gross National Income (GNI), data from the European Cystic Fibrosis Society Patient Registry were utilised.

METHODS

Annual data including age, forced expiratory volume in 1 s (FEV1), anthropometry, genotype, respiratory cultures and CF-related diabetes (CFRD) were retrieved between 2011 and 2021. All countries were stratified into GNI per capita to reflect differences within Europe.

RESULTS

A consistent improvement in FEV1 % pred and survival was observed among the 47 621 people with CF (pwCF), including subjects with chronic Pseudomonas aeruginosa infection, CFRD and/or undernutrition. Mean values of FEV1 % pred changed from 85% to 94.2% for children and from 63.6% to 74.7% for adults. FEV1 % pred further increased among those carrying the F508del mutation in 2021, when elexacaftor/tezacaftor/ivacaftor was available. The number of adult pwCF increased from 13 312 in 2011 to 21 168 in 2021, showing a 60% increase. PwCF living in European lower income countries did not demonstrate a significant annual increase in FEV1 % pred or in the number of adults.

CONCLUSION

This pan-European analysis demonstrates a consistent improvement in FEV1 % pred, number of adult pwCF and survival over the last decade only in European higher and middle income countries. Urgent action is needed in the lower income countries where such improvement was not observed. The notable improvement observed in pwCF carrying the F508del mutation emphasises the need to develop treatments for all CF mutations.

Use of elexacaftor/tezacaftor/ivacaftor leads to changes in detection frequencies of Staphylococcus aureus and Pseudomonas aeruginosa dependent on age and lung function in people with cystic fibrosis

OBJECTIVES

The impressive improvements of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) function by elexacaftor/tezacaftor/ivacaftor (ETI) result in changes in the detection frequencies of Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA). We assessed determinants of the response to ETI with regards to SA and PA detection frequencies as documented in the German CF registry for people with CF (pwCF) ≥12 years.

METHODS

We evaluated changes in the detection frequencies of SA and PA for 21 months before and after initiation of ETI and used different statistical tests to identify determinants of detection changes.

RESULTS

We included data from 1092 pwCF with results from culture-dependent diagnostics for SA and PA detection from 7944 microbiological samples before and 6.845 microbiological samples after initiation of ETI. Detections of SA decreased from 54.3% to 44.3% and 40.2% and those of PA from 39.9% to 31.9% and 22.6% 3 and 21 months after initiation of therapy, respectively (all P <0.001). Reduction of SA and PA were observed in throat swabs and sputa, associated significantly with age, previous lung function, and were dependent on pre-ETI colonization status.

CONCLUSIONS

The different patterns of reductions of SA and PA suggest that pathogen-specific biological processes govern the responsiveness of microbiological colonization towards ETI in pwCF.

Elexacaftor/Tezacaftor/Ivacaftor Treatment and Depression-related Events

Rationale: Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) has been shown to be safe and efficacious in people with cystic fibrosis (pwCF) aged 2 years and older with at least one F508del-CFTR allele or more. After U.S. approval in 2019, reports emerged of depression-related adverse events in pwCF treated with ELX/TEZ/IVA. Objectives: To review available evidence on depression-related events in pwCF treated with ELX/TEZ/IVA in the context of background epidemiology in pwCF. Methods: Safety data from 14 ELX/TEZ/IVA clinical trials and 10 trials of CF transmembrane conductance regulator (CFTR) modulators in which placebo was administered, along with data from CF registries in the United States and Germany and cumulative postmarketing adverse event data from 61,499 pwCF who initiated ELX/TEZ/IVA after initial approval in the United States (October 2019) through October 2022, were reviewed and used to calculate exposure-adjusted rates of depression-related adverse events and prevalence of depression. In addition, a scientific literature review was conducted to identify ELX/TEZ/IVA publications reporting depression-related events or changes in depressive symptoms after treatment initiation. Measurements and Main Results: In clinical trials, the exposure-adjusted rate of any depression-related adverse event was 3.32/100 person years (PY) in the pooled ELX/TEZ/IVA group (n = 1,711) and 3.24/100 PY in the pooled placebo group (n = 1,369). The exposure-adjusted rates of suicidal ideation and suicide attempt were also similar between the pooled ELX/TEZ/IVA group and pooled placebo group (ideation: 0.23/100 PY vs. 0.28/100 PY; attempt: 0.08/100 PY vs. 0.14/100 PY). In the postmarketing setting, the exposure-adjusted reporting rates of depression-related events were low in context of the background prevalence in pwCF (all depression-related events: 1.29/PY; suicidal ideation: 0.12/100 PY; and suicide attempt: 0.05/100 PY). Assessments of individual case reports were confounded by preexisting mental health conditions, intercurrent psychosocial stressors (including coronavirus disease [COVID-19] lockdowns), and the heterogeneous and fluctuating nature of depression. Data from CF registries in the United States and Germany showed that patterns of depression prevalence in pwCF exposed to ELX/TEZ/IVA did not change after treatment initiation. Published studies utilizing the nine-item Patient Health Questionnaire did not show evidence of worsening depression symptoms in pwCF treated with ELX/TEZ/IVA. Conclusions: Our review of data from clinical trials, postmarketing reports, an ongoing registry-based ELX/TEZ/IVA postauthorization safety study, and peer-reviewed literature suggests that depression symptoms and depression-related events reported in pwCF treated with ELX/TEZ/IVA are generally consistent with background epidemiology of these events in the CF population and do not suggest a causal relationship with ELX/TEZ/IVA treatment.

One year of treatment with elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis homozygous for the F508del mutation causes a significant increase in liver biochemical indexes

Introduction: Modulators of cystic fibrosis transmembrane conductance regulator mutated protein significantly improved the outcome of patients with cystic fibrosis (CF). We describe 63 patients who were independently followed up in two CF regional centers (i.e., Campania and Tuscany regions). Methods: All patients were homozygous for the F508del mutation and were treated with lumacaftor/ivacaftor (LI) for 3 years, followed by 1 year of treatment with elexacaftor/tezacaftor/ivacaftor (ETI). We studied the biochemical parameters of liver damage and cholesterol metabolism. Results: Beyond the improvement of BMI and lung function with LI treatment and even more with ETI, we found that the 3 years of LI treatment significantly improved liver function parameters (total and conjugated bilirubin, ALT, AP, and GGT), while the subsequent ETI treatment caused a significant increase of such parameters. Discussion: We confirm that treatment with LI does not correct hypocholesterolemia, whereas treatment with ETI significantly increases serum cholesterol. Such an increase is likely due to enhanced de novo biosynthesis, as indicated by the significant increase in serum lathosterol, and it is likely that the subsequent liver cholesterol accumulation may contribute to triggering inflammation and worsening liver biochemical indexes. The increase in serum bilirubin and ALT that we observed in approximately 94% and 84% of patients treated with ETI, respectively, suggests further investigation of the impact of ETI therapy on liver function indexes.

Use of elexacaftor+tezacaftor+ivacaftor in individuals with cystic fibrosis and at least one F508del allele: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effect of treatment with the combination of three cystic fibrosis transmembrane conductance regulator (CFTR) modulators-elexacaftor+tezacaftor+ivacaftor (ETI)-on important clinical endpoints in individuals with cystic fibrosis.

METHODS

This was a systematic review and meta-analysis of randomized clinical trials that compared the use of ETI in individuals with CF and at least one F508del allele with that of placebo or with an active comparator such as other combinations of CFTR modulators, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations and the Patients of interest, Intervention to be studied, Comparison of interventions, and Outcome of interest (PICO) methodology. We searched the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov from their inception to December 26th, 2022. The risk of bias was assessed using the Cochrane risk-of-bias tool, and the quality of evidence was based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

We retrieved 54 studies in the primary search. Of these, 6 met the inclusion criteria and were analyzed (1,127 patients; 577 and 550 in the intervention and control groups, respectively). The meta-analysis revealed that the use of ETI increased FEV1% [risk difference (RD), +10.47%; 95% CI, 6.88-14.06], reduced the number of acute pulmonary exacerbations (RD, -0.16; 95% CI, -0.28 to -0.04), and improved quality of life (RD, +14.93; 95% CI, 9.98-19.89) and BMI (RD, +1.07 kg/m2; 95% CI, 0.90-1.25). Adverse events did not differ between groups (RD, -0.03; 95% CI, -0.08 to 0.01), and none of the studies reported deaths.

CONCLUSIONS

Our findings demonstrate that ETI treatment substantially improves clinically significant, patient-centered outcomes.

The cost of simplifying treatments for cystic fibrosis: Implications of the SIMPLIFY trial

BACKGROUND

Dornase alfa and hypertonic saline are mucoactive therapies that can improve respiratory symptoms in people with cystic fibrosis (CF). A recent randomized control trial showed that participants with well-preserved pulmonary function taking elexacaftor + tezacaftor + ivacaftor (ETI) who discontinued dornase alfa or hypertonic saline for 6 weeks had no clinically meaningful decline in lung function. This may prompt discussions with care providers regarding ongoing use of these medications.

OBJECTIVE

To compare the costs of outpatient medications between people taking ETI who continued or discontinued (1) dornase alfa or (2) hypertonic saline from 2 clinical trials and project cost differences in the US CF population if these 2 medications were used only intermittently for symptom relief instead of chronically.

METHODS

The SIMPLIFY study was 2 parallel multicenter trials that randomized participants 1:1 to either continue or discontinue therapy. To estimate costs, we used data from the Merative MarketScan Databases to identify people with CF from 2020 to 2021. Our primary outcomes were differences in costs of outpatient prescription drugs among those who continued vs discontinued dornase alfa and, separately, hypertonic saline. We obtained adjusted differences in median costs. To estimate the annual cost savings if the population of people with CF taking ETI used these medications only intermittently, we multiplied the proportion of people in MarketScan with CF diagnoses who were taking each of these medications by the median cost savings per year and subtracted the cost of "rescue" use.

RESULTS

A total of 392 participants from the dornase alfa trial and 273 from the hypertonic saline trial were included in analyses. The adjusted difference in median medication costs was not significant for the hypertonic saline trial, but we observed a significantly decreased 6-week cost of medications in the dornase alfa trial (adjusted median difference in costs between discontinue and continue of $5,860 (95% CI = $4,870-$6,850); P < 0.0001). We estimated that two-thirds of people with CF use ETI and dornase alfa in the United States; if they discontinued dornase alfa except for intermittent use, the resulting annual savings would be $1.21 billion.

CONCLUSIONS

Although the costs of dornase alfa and hypertonic saline are smaller compared with ETI, reduction in use would lead to substantial prescription drug cost savings and reduce the treatment burden. However, individual benefits of these therapies should be considered, and decisions regarding changes in therapy remain an important discussion between people with CF and their providers. Study registration number: NCT04378153.

Impact of Elexacaftor/Tezacaftor/Ivacaftor on Healthcare Resource Utilization and Associated Costs Among People With Cystic Fibrosis in the US: A Retrospective Claims Analysis

INTRODUCTION

Cystic fibrosis (CF) is a life-limiting genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) is a CFTR modulator (CFTRm) that targets the underlying cause of CF. Based on safety and efficacy demonstrated in clinical trials, ELX/TEZ/IVA is approved in the US for the treatment of CF in people aged ≥ 2 years who have ≥ 1 F508del-CFTR mutation or a CFTR mutation that is responsive to ELX/TEZ/IVA based on in vitro data. While ELX/TEZ/IVA demonstrated unprecedented improvements in lung function and dramatic reductions in pulmonary exacerbations (PEx) and associated hospitalizations in clinical trials, a limited number of studies have examined the impact of ELX/TEZ/IVA on healthcare resource utilization (HCRU) and associated costs in a real-world setting. The aim of this retrospective study was to evaluate changes in PEx, HCRU, and associated non-CFTRm healthcare costs following initiation of ELX/TEZ/IVA among people with CF aged ≥ 12 years in the US.

METHODS

We evaluated the rates of PEx, HCRU, and associated costs before and after initiation of ELX/TEZ/IVA in people with CF aged ≥ 12 years using data from the Merative MarketScan® Commercial Claims and Encounters Database and the Merative Multi-State Medicaid Database from April 21, 2019 to December 31, 2020. Because the study period included time following the onset of the COVID-19 pandemic, we limited our primary analysis to the period prior to the pandemic (October 21, 2019 to March 12, 2020). Outcomes following the onset of the pandemic (March 13 to December 31, 2020) were examined in an exploratory analysis.

RESULTS

In both commercially insured and Medicaid-insured people with CF, ELX/TEZ/IVA was associated with reductions in PEx, hospitalizations, and associated costs prior to the COVID-19 pandemic, and these reductions were maintained following the onset of the pandemic.

CONCLUSIONS

These findings suggest that ELX/TEZ/IVA reduces the burden and costs associated with PEx and hospitalizations in people with CF.

Long-term safety and efficacy of elexacaftor/tezacaftor/ivacaftor in people with cystic fibrosis and at least one F508del allele: 144-week interim results from a 192-week open-label extension study

BACKGROUND

In two pivotal phase 3 trials, up to 24 weeks of treatment with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) was efficacious and safe in patients with cystic fibrosis (CF) ≥12 years of age who have at least one F508del allele. The aim of this study is to assess long-term safety and efficacy of ELX/TEZ/IVA in these patients.

METHODS

In this phase 3, open-label, single-arm extension study, participants with F508del-minimal function (from a 24-week parent study; n=399) or F508del-F508del (from a 4-week parent study; n=107) genotypes receive ELX/TEZ/IVA at the same dose (ELX 200 mg once daily, TEZ 100 mg once daily and IVA 150 mg every 12 h). The primary end-point is safety and tolerability. A prespecified interim analysis was conducted when the last participant reached the Week 144 visit.

RESULTS

At the Week 144 interim analysis, mean duration of exposure to ELX/TEZ/IVA in the extension study was 151.1 weeks. Exposure-adjusted rates of adverse events (AEs) (586.6 events per 100 participant-years) and serious AEs (22.4 events per 100 participant-years) were lower than in the ELX/TEZ/IVA treatment group in the 24-week parent study (1096.0 and 36.9 events per 100 participant-years, respectively); most participants had AEs classified as mild (16.4% of participants) or moderate (60.3% of participants) in severity. 14 participants (2.8%) had AEs that led to treatment discontinuation. Following initiation of ELX/TEZ/IVA, participants had increases in forced expiratory volume in 1 s (FEV1) percentage predicted, Cystic Fibrosis Questionnaire-Revised respiratory domain score and body mass index, and had decreases in sweat chloride concentration and pulmonary exacerbation rates that were maintained over the interim analysis period. The mean annualised rate of change in FEV1 % pred was +0.07 (95% CI -0.12-0.26) percentage points among the participants.

CONCLUSIONS

ELX/TEZ/IVA was generally safe and well tolerated, with a safety profile consistent with the 24-week parent study. Participants had sustained improvements in lung function, respiratory symptoms, CF transmembrane conductance regulator function, pulmonary exacerbation rates and nutritional status. These results support the favourable safety profile and durable, disease-modifying clinical benefits of ELX/TEZ/IVA.

Unplanned pregnancies following the introduction of elexacaftor/tezacaftor/ivacaftor therapy in women with cystic fibrosis

Cystic fibrosis (CF) causes infertility and subfertility due to various factors, including altered cervical mucus, delayed puberty, and hormonal imbalances. With the introduction of the CFTR modulator therapy elexacaftor-tezacaftor-ivacaftor, we have observed an increase in unplanned pregnancies among women undergoing ETI treatment in our CF center, despite repeated recommendations for strict fertility monitoring. It appears that these pregnancies are more likely attributed to reduced attention to the possibility of conception rather than contraceptive failure. The perception of subfertility developed by women with CF over time, before the era of modulators, can influence their long-term habits and lead to the underuse of contraceptive methods. While further research is needed to fully understand the effects of ETI on fertility, healthcare providers should be attentive to the fertility concerns of women with CF, particularly those treated with modulators in adulthood.

Breath of fresh insight: unraveling the evolution of our understanding of cystic fibrosis pulmonary exacerbations

PURPOSE OF REVIEW

Pulmonary exacerbations are critical events with significant negative impacts in persons with cystic fibrosis, but their diagnosis and management are highly variable. Highly effective modulator therapies have greatly improved health and reduced exacerbation events, but have also reshaped how they present. This review discusses the complexities of the diagnosis and management of pulmonary exacerbations as well as the emerging work and evidence in this area.

RECENT FINDINGS

The shifting epidemiology and our understanding of risk factors for pulmonary exacerbations are discussed. As symptoms may be more subtle in the modulator context, novel technologies including studies of remote monitoring are presented. The continued relevance of pulmonary exacerbations, the heterogeneity in their management, as well as current and forthcoming clinical trials to optimize treatment approaches are detailed.

SUMMARY

In spite of the dramatic reductions in pulmonary exacerbations, airway infections persist, a proportion of persons with cystic fibrosis either on or off modulator therapies continue to experience exacerbation events, and long-term data is lacking. Innovative approaches and studies will be crucial to enable standardized and generalizable strategies to improve outcomes in persons with cystic fibrosis.

Chronic daily respiratory care needs in people with cystic fibrosis treated with highly effective cystic fibrosis transmembrane conductance regulator modulators

PURPOSE OF REVIEW

Cystic fibrosis is a genetic disease that increases risk of death from respiratory failure because of impairment in mucociliary clearance. Complex daily care regimens including medications and airway clearance techniques (ACTs) aim to preserve lung function and alleviate symptoms for people with cystic fibrosis (pwCF). The success of highly effective modulator therapy (HEMT) permits evaluation of treatment simplification. In this review, we evaluate adjustments made in daily respiratory care among pwCF taking HEMT and the feasibility of treatment simplification.

RECENT FINDINGS

Treatment simplification has been identified as a top priority among pwCF, with recent studies showing pwCF are willing to sacrifice mild to moderate amounts of lung function and longevity to reduce treatment burden. Retrospective studies have shown that patients taking HEMT with better baseline lung function have lower adherence to and prescription of inhaled medications. A randomized, controlled trial found that short-term discontinuation of dornase alfa or hypertonic saline was clinically noninferior to continuation of these medications. Major knowledge gaps remain about withdrawing ACTs.

SUMMARY

This review highlights trials evaluating the feasibility of treatment simplification among pwCF taking HEMT. More data is needed to evaluate approaches to simplification in this phenotypically diverse patient population.

Cystic fibrosis liver disease in the post-modulator era

PURPOSE OF REVIEW

Highly effective modulators of cystic fibrosis transmembrane conductance regulator (CFTR) function have had dramatic impact on pulmonary and nutritional outcomes in persons with cystic fibrosis (pwCF). The impact on liver disease in pwCF was not the focus of the registration trials. The purpose of this review is to assess the current literature on the impact of HEMT on liver disease, progression, regression, and safety.

RECENT FINDINGS

Short-term studies of HEMT in pwCF have shown that there is no significant impact on the frequency of liver enzyme abnormalities. There is no evidence for significant improvement in liver enzymes over time on HEMT therapy. There is conflicting data on improvement in liver fibrosis determined by fibrosis indices (APRI and GPR) or elastography. One study showed improvement, and another showed worsening in younger (<20 years old) pwCF. There are reports of resolution or improvement in hepatic steatosis. There are rare reports of severe acute hepatitis and one report of hepatic decompensation leading to liver transplantation due to drug-induced liver disease.

SUMMARY

HEMT have not been shown to have a significant impact on improving liver disease or preventing fibrosis with short-term therapy. Longer studies are needed to assess the impact of HEMT on liver disease in pwCF.

Understanding and addressing the needs of people with cystic fibrosis in the era of CFTR modulator therapy

Cystic fibrosis is a multiorgan disease caused by impaired function of the cystic fibrosis transmembrane conductance regulator (CFTR). Since the introduction of the CFTR modulator combination elexacaftor-tezacaftor-ivacaftor (ETI), which acts directly on mutant CFTR to enhance its activity, most people with cystic fibrosis (pwCF) have seen pronounced reductions in symptoms, and studies project marked increases in life expectancy for pwCF who are eligible for ETI. However, modulator therapy has not cured cystic fibrosis and the success of CFTR modulators has resulted in immediate questions about the new state of cystic fibrosis disease and clinical challenges in the care of pwCF. In this Series paper, we summarise key questions about cystic fibrosis disease in the era of modulator therapy, highlighting state-of-the-art research and clinical practices, knowledge gaps, new challenges faced by pwCF and the potential for future health-care challenges, and the pressing need for additional therapies to treat the underlying genetic or molecular causes of cystic fibrosis.

CFTR modulator therapy: transforming the landscape of clinical care in cystic fibrosis

Following discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in 1989 and subsequent elucidation of the varied CFTR protein abnormalities that result, a new era of cystic fibrosis management has emerged-one in which scientific principles translated from the bench to the bedside have enabled us to potentially treat the basic defect in the majority of children and adults with cystic fibrosis, with a resultant burgeoning adult cystic fibrosis population. However, the long-term effects of these therapies on the multiple manifestations of cystic fibrosis are still under investigation. Understanding the effects of modulators in populations excluded from clinical trials is also crucial. Furthermore, establishing appropriate disease measures to assess efficacy in the youngest potential trial participants and in those whose post-modulator lung function is in the typical range for people without chronic lung disease is essential for continued drug development. Finally, recognising that a health outcome gap has been created for some people and widened for others who are not eligible for, cannot tolerate, or do not have access to modulators is important.