Real-life efficacy and safety of elexacaftor/tezacaftor/ivacaftor on severe cystic fibrosis lung disease patients

Wellness in the modulator era: An observational study of the impact of CFTR modulator therapy on the well-being of people with cystic fibrosis

BACKGROUND

People with cystic fibrosis (PwCF) have experienced substantial improvements in health following use of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies. However, less is known about how modulator therapies impact well-being.

METHODS

We used a cross-sectional observational study to identify relationships between CFTR modulator therapies, health-related quality of life (HRQoL), and well-being. Adult PwCF and caregivers of children with CF completed the Wellness in the Modulator Era (Well-ME) survey between June 22 and July 31, 2022. HRQoL was measured with PROMIS Global 10/Global 7 + 2 Parent Proxy. We used a mixed methods analysis to compare experiences and concerns of PwCF who currently (n = 665), no longer (n = 51), or never (n = 184) took modulator therapy.

RESULTS

Adult PwCF taking a modulator (n = 416) reported better PROMIS global physical health than those who no longer (n = 37) or never took a modulator (n = 94) and better PROMIS global mental health than those who never took a modulator. Caregiver-reported HRQoL was similar across children with CF who currently, no longer, or never took a modulator. PwCF taking a modulator reported larger improvements in physical health, quality of life, social well-being, and treatment burden than those who no longer or never took a modulator. Nearly one-quarter (23 %) of PwCF taking modulator therapy reported worsening of mental well-being.

CONCLUSIONS

This study expands our knowledge of well-being among PwCF in the CFTR modulator era as reported by patients and parents. Findings lay the groundwork for establishing future research priorities, policy efforts, and communications in areas that improve well-being for PwCF.

Dried Blood Spot Method Development and Clinical Validation for the Analysis of Elexacaftor, Elexacaftor-M23, Tezacaftor, Tezacaftor-M1, Ivacaftor, Ivacaftor Carboxylate, and Hydroxymethyl Ivacaftor Using LC-MS/MS

BACKGROUND

The highly effective Cystic Fibrosis Transmembrane conductance Regulator (CFTR) modulator, elexacaftor-tezacaftor-ivacaftor, is now widely being used by people with cystic fibrosis. However, few independent studies have detailed the pharmacokinetics (PK) of CFTR modulators. Blood collection by venipuncture is the gold standard for PK measurements, but it is invasive. The aim of this study was to develop and clinically validate a quantification method for elexacaftor, tezacaftor, ivacaftor, and their main metabolites in dried blood spots (DBSs) using liquid chromatography with tandem mass spectrometry.

METHODS

Linearity, accuracy, precision, stability, hematocrit (Hct), spot-to-spot carryover, spot volume, and extraction efficiency were validated in DBS for all analytes. The clinical validation of elexacaftor-tezacaftor-ivacaftor in patients was performed by comparing 21 DBS samples with matched plasma samples.

RESULTS

The preset requirements for linearity, within-run and between-run accuracy, precision, Hct, spot volume, and extraction efficiency were met. Puncher carryover was observed and resolved by punching 3 blanks after each sample. The samples remained stable and showed no notable degradation across the tested temperatures and time intervals. Corrected DBS values with the Passing-Bablok regression equation showed good agreement in Bland-Altman plots, and acceptance values were within 20% of the mean for a minimum of 67% of the repeats, according to the EMA guidelines.

CONCLUSIONS

A quantification method for the analysis of elexacaftor, tezacaftor, ivacaftor, and their main metabolites was developed and clinically validated in DBS. This method could be valuable in both clinical care and research to address unanswered PK questions regarding CFTR modulators.

[Cystic fibrosis in childhood and adulthood]

BACKGROUND

Cystic fibrosis (CF, or mucoviscidosis) is one of the rare diseases with a fatal course and with the highest prevalence. Formerly known as a purely childhood disease, this multisystemic disease follows an autosomal recessive inheritance pattern and results in a malfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) channel, leading to the production of viscous secretions. The prognosis and outcome of CF are determined by the severity of the involvement of the lungs. Other typically affected organs include the pancreas, liver and intestines.

OBJECTIVE

This article reviews the clinical presentation and evolution of CF with a focus on the new era of the highly effective CFTR modulator treatment.

MATERIAL AND METHODS

An overview of the current state of knowledge on the care for CF patients is presented.

RESULTS AND DISCUSSION

The introduction of the CF newborn screening, the increased understanding of the disease and the development of novel treatment options have substantially increased the quality of life and life expectancy of people with CF. As a result, more than half of CF patients in Germany are now older than 18 years of age and the complications of a chronic disease as well as organ damage due to the intensive treatment are gaining in importance. The highly effective CFTR modulator treatment results in a significant improvement in CFTR function, lung function, body mass index and quality of life and is available to approximately 90% of patients in Germany, based on the genotype. Nevertheless, further research including the development of causal treatment, e.g., gene therapy, targeting the underlying defect in the remaining 10% of CF patients, is urgently needed. Even in adult patients, CF with a mild course or a CFTR-related disease should be considered, e.g., in cases of bronchiectasis and/or recurrent abdominal complaints.

A longitudinal analysis of respiratory symptoms in people with cystic fibrosis with advanced lung disease on and off ETI

People with CF (PwCF), particularly those with advanced lung disease (ALD), experience frequent respiratory symptoms. A major CF breakthrough was the approval of elexacaftor/tezacaftor/ivacaftor (ETI) in 2019, which has been shown to improve symptoms and lung function in the CF population, and decrease pulmonary exacerbations. The purpose of this study was to analyze longitudinal changes in respiratory symptoms over 24 months in ETI-treated and untreated PwCF with ALD Symptoms were measured among CF adults with ppFEV1 < 40% (N = 48, 24 ETI-treated, 24 untreated) using the CFRSD-CRISS and the CFQ-R [respiratory]. Two multilevel growth models assessed the rate of change in symptoms overall and within the ETI-treated and untreated groups. PwCF on ETI had significantly lower symptom severity over 24 months than those not on ETI as measured by the CRISS and CFQ-R. The ETI-treated group maintained an -11.7 and +19.3 point difference(p<0.01) in CRISS and CFQ-R scores over the study compared to the non-ETI group, achieving minimal clinically important differences on average between groups on both instruments. No change in the symptom burden trajectory between groups was observed (p = 0.58). Even with ALD, ETI-treated PwCF have a lower respiratory burden than those not on ETI. This may be confounded by survivorship bias in the non-ETI group. Of note, in this ALD cohort, neither instrument demonstrated ceiling effects. Our results suggest that, while ETI has significantly improved the lived experience, PwCF with ALD are still plagued by respiratory symptoms.

Efficacy and safety profile of elexacaftor-tezacaftor-ivacaftor triple therapy on cystic fibrosis: a systematic review and single arm meta-analysis

Background: Elexacaftor-Tezacaftor-Ivacaftor (ELE/TEZ/IVA) is believed to be an effective and well-tolerated treatment for cystic fibrosis (CF), but the exact efficacy and safety profile are still unknown. Objective: This study aimed to clarify the extent of functional restoration when patients are given with triple combination treatment and demonstrate the prevalence of adverse events, to evaluate the overall profile of ELE/TEZ/IVA on CF. Methods: A literature search was conducted in PubMed, Web of Science and Cochrane Library. Random effects single-arm meta-analysis was performed to decipher the basal characteristics of CF, the improvement and safety profile after ELE/TEZ/IVA treatment. Results: A total 53 studies were included in this analysis. For all the patients in included studies. 4 weeks after ELE/TEZ/IVA treatment, the increasement of percentage of predicted Forced Expiratory Volume in the first second (ppFEV1) was 9.23% (95%CI, 7.77%-10.70%), the change of percentage of predicted Forced Vital Capacity (ppFVC) was 7.67% (95%CI, 2.15%-13.20%), and the absolute change of Cystic Fibrosis Questionnaire-Revised (CFQ-R) score was 21.46 points (95%CI, 18.26-24.67 points). The Sweat chloride (SwCl) was significantly decreased with the absolute change of -41.82 mmol/L (95%CI, -44.38 to -39.25 mmol/L). 24 weeks after treatment, the increasement of ppFEV1 was 12.57% (95%CI, 11.24%-13.90%), the increasement of ppFVC was 10.44% (95%CI, 7.26%-13.63%), and the absolute change of CFQ-R score was 19.29 points (95%CI, 17.19-21.39 points). The SwCl was significantly decreased with the absolute change of -51.53 mmol/L (95%CI, -56.12 to -46.94 mmol/L). The lung clearance index2.5 (LCI2.5) was also decreased by 1.74 units (95%CI, -2.42 to -1.07 units). The body mass index increased by 1.23 kg/m2 (95%CI, 0.89-1.57 kg/m2). As for adverse events, 0.824 (95%CI, 0.769-0.879) occurred during ELE/TEZ/IVA period, while the incidence of severe adverse events was 0.066 (95%CI, 0.028-0.104). Conclusion: ELE/TEZ/IVA is a highly effective strategy and relatively safe for CF patients and needs to be sustained to achieve better efficacy. Systematic Review Registration: Identifier: CRD42023441840.

Use of CFTR modulators in special populations, part 2: Severe lung disease

Safety and efficacy data surrounding cystic fibrosis transmembrane regulator (CFTR) modulator administration for people with CF (pwCF) and severe lung disease elect has remained unclear as a result of exclusion from key trials. A scoping review of English language articles from the period of 1 January 2012, to 31 July 2023 was conducted utilizing PubMed and EmBase databases with the following terms: "severe lung disease" OR "advanced lung disease" AND "ivacaftor OR lumacaftor OR tezacaftor OR elexacaftor"; "cystic fibrosis transmembrane conductance regulator" AND "off label drug use." Search results were reviewed by title and abstract for relevance. Twenty articles specific to CFTR modulator use in the setting of severe lung disease were included for review, with few specific to pediatric-aged pwCF. PwCF and severe lung disease experienced significant improvement in pulmonary function, body weight, number of IV antibiotic days, and quality of life. A few studies reported a transient decline in pulmonary function among pwCF shortly after LUM/IVA initiation. However, preemptive reductions in the dose of LUM/IVA may mitigate this reaction. ELE/TEZ/IVA utilization in pwCF and severe lung disease appears to be devoid of the transient decline in pulmonary function observed with LUM/IVA while providing the same clinical benefit. Current available data regarding use of CFTR modulators in pwCF and severe lung disease is reassuring; however, there remains a lack data regarding outcomes among the pediatric population including long-term outcomes. Therefore, treatment decisions should be individualized and coproduced.

Long-term clinical outcomes of elexacaftor/tezacaftor/ivacaftor therapy in adults with cystic fibrosis and advanced pulmonary disease

BACKGROUND

The combination of cystic fibrosis transmembrane conductance regulator (CFTR) modulators elexacaftor, tezacaftor and ivacaftor (ELX/TEZ/IVA) has been approved for treatment of cystic fibrosis (CF) patients (pwCF) homozygous and heterozygous for Phe508del. We aim to assess the long-term effects of ELX/TEZ/IVA therapy on clinical outcomes in severe pwCF.

METHODS

Lung function, pulmonary exacerbation (PEx), sweat chloride concentration, body mass index (BMI) and the respiratory domain of the cystic fibrosis questionnaire-revised (CFQ-R RD) were prospectively evaluated in a cohort of pwCF who were candidates for inclusion in a compassionate program of ELX/TEZ/IVA therapy. All procedures were performed at baseline and then at 12 and 24 months after initiation of modulator therapy. The number of PExs in the year before the study enrollment was collected from our records.

RESULTS

Thirty-six adult pwCF (median age 36.7 years; BMI 19.8 kg/m2; FEV1 36.5% predicted) were recruited from 2019. At 12 and 24 months after initiation, the absolute change in ppFEV1 (percent predicted forced expiratory volume in 1 s) from baseline was +12.5% (p < 0.0001) and +13% (p < 0.0001), respectively. A median of 4.0 exacerbations per patient was reported in the preceding year, while the median number of PExs was 0.0 and 1.0 after 12 and 24 months, respectively, of modulator therapy (both p < 0.0001). After 12 and 24 months of ELX/TEZ/IVA therapy, the CFQ-R RD score improved by 22.4 points (p < 0.0001) and 16.7 points (p < 0.0001), and sweat chloride levels decreased by 65.5 mmol/L (p < 0.0001) and 60 mmol/L (p < 0.0001), respectively. BMI significantly increased.

CONCLUSIONS

Long-term ELX/TEZ/IVA combination therapy markedly impacts the clinical status of patients with severe CF, showing a sustained improvement in lung function and PEx rate.

Cystic fibrosis year in review 2022

Remarkable medical advancements have been made for people with cystic fibrosis (CF) in recent years, with an abundance of research continuing to be conducted worldwide. With concern for limitations in access to highly effective CFTR modulators, as well as the recent Coronavirus Disease-19 pandemic, there has been a consistent effort to understand and improve CF screening, disease burden, diagnosis, and management. Our aim in this review is to present articles from 2022 with an emphasis on clinically relevant studies. We hope this will serve as a broad overview of the research published in the past year.

Real-life impact of highly effective CFTR modulator therapy in children with cystic fibrosis

Introduction: Recently, cystic fibrosis transmembrane regulator modulator therapy with elexacaftor/tezacaftor/ivacaftor has become available for children with cystic fibrosis (CF) carrying at least one F508del mutation. Objective: To assess the intermediate term effects of elexacaftor/tezacaftor/ivacaftor in children with cystic fibrosis in a real-world setting. Methods: We performed a retrospective analysis of records of children with cystic fibrosis, who started elexacaftor/tezacaftor/ivacaftor between 8/2020 and 10/2022. Pulmonary function tests, nutritional status, sweat chloride and laboratory data were assessed before, 3 and 6 months after the start of elexacaftor/tezacaftor/ivacaftor respectively. Results: Elexacaftor/tezacaftor/ivacaftor was started in 22 children 6-11 years and in 24 children 12-17 years. Twenty-seven (59%) patients were homozygous for F508del (F/F) and 23 (50%) patients were transitioned from ivacaftor/lumacaftor (IVA/LUM) or tezacaftor/ivacaftor (TEZ/IVA) to elexacaftor/tezacaftor/ivacaftor. Overall, mean sweat chloride concentration decreased by 59.3 mmol/L (95% confidence interval: -65.0 to -53.7 mmol/L, p < 0.0001) under elexacaftor/tezacaftor/ivacaftor. Sweat chloride concentration also decreased significantly after transition from IVA/LUM or TEZ/IVA to elexacaftor/tezacaftor/ivacaftor (-47.8 mmol/l; 95% confidence interval: -57.6 to -37.8 mmol/l, n = 14, p < 0.0001). Sweat chloride reduction was more marked in children with the F/F than in those with the F/MF genotype (69.4 vs 45.9 mmol/L, p < 0.0001). At 3 months follow-up, body-mass-index-z-score increased by 0.31 (95% CI, 0.2-0.42, p < 0.0001) with no further increase at 6 months. BMI-for-age-z-score was more markedly improved in the older group. Overall pulmonary function (percent predicted FEV₁) at 3 months follow-up increased by 11.4% (95% CI: 8.0-14.9, p < 0.0001) with no further significant change after 6 months. No significant differences were noted between the age groups. Children with the F/MF genotype had a greater benefit regarding nutritional status and pulmonary function tests than those with the F/F genotype. Adverse events led to elexacaftor/tezacaftor/ivacaftor dose reduction in three cases and a temporary interruption of therapy in four cases. Conclusion: In a real-world setting, elexacaftor/tezacaftor/ivacaftor therapy had beneficial clinical effects and a good safety profile in eligible children with cystic fibrosis comparable to previously published data from controlled clinical trials. The positive impact on pulmonary function tests and nutritional status seen after 3 months of elexacaftor/tezacaftor/ivacaftor therapy was sustained at 6 months follow-up.

Post-approval studies with the CFTR modulators Elexacaftor-Tezacaftor—Ivacaftor

Triple combination therapy with the CFTR modulators elexacaftor (ELX), tezacaftor (TEZ) and ivacaftor (IVA) has been qualified as a game changer in cystic fibrosis (CF). We provide an overview of the body of literature on ELX/TEZ/IVA published between November 2019 and February 2023 after approval by the regulators. Recombinant ELX/TEZ/IVA-bound Phe508del CFTR exhibits a wild type conformationin vitro, but in patient’s tissue a CFTR glyoisoform is synthesized that is distinct from the wild type and Phe508del isoforms. ELX/TEZ/IVA therapy improved the quality of life of people with CF in the real-life setting irrespective of their anthropometry and lung function at baseline. ELX/TEZ/IVA improved sinonasal and abdominal disease, lung function and morphology, airway microbiology and the basic defect of impaired epithelial chloride and bicarbonate transport. Pregnancy rates were increasing in women with CF. Side effects of mental status changes deserve particular attention in the future.

Elexacaftor-Tezacaftor-Ivacaftor: A Life-Changing Triple Combination of CFTR Modulator Drugs for Cystic Fibrosis

Cystic fibrosis (CF) is a potentially fatal monogenic disease that causes a progressive multisystemic pathology. Over the last decade, the introduction of CF transmembrane conductance regulator (CFTR) modulator drugs into clinical practice has profoundly modified the lives of many people with CF (PwCF) by targeting the fundamental cause of the disease. These drugs consist of the potentiator ivacaftor (VX-770) and the correctors lumacaftor (VX-809), tezacaftor (VX-661), and elexacaftor (VX-445). In particular, the triple combination of CFTR modulators composed of elexacaftor, tezacaftor, and ivacaftor (ETI) represents a life-changing therapy for the majority of PwCF worldwide. A growing number of clinical studies have demonstrated the safety and efficacy of ETI therapy in both short- and long-term (up to two years of follow-up to date) and its ability to significantly reduce pulmonary and gastrointestinal manifestations, sweat chloride concentration, exocrine pancreatic dysfunction, and infertility/subfertility, among other disease signs and symptoms. Nevertheless, ETI therapy-related adverse effects have also been reported, and close monitoring by a multidisciplinary healthcare team remains vital. This review aims to address and discuss the major therapeutic benefits and adverse effects reported by the clinical use of ETI therapy for PwCF.