Use Of Ivacaftor Research Articles

Real world outcomes of CFTR modulator therapy in Australian adults and children

BackgroundRecent advances in CFTR modulator therapy have the potential to change the face of cystic fibrosis (CF). This retrospective observational study describes real world experience of the four available CFTR modulators in adults and children with CF in a single centre in Melbourne, Australia. MethodData were collected for all patients treated with CFTR modulators at MonashCF between May 2012 and September 2020. Primary outcomes included lung function, admission days and BMI/BMI centile over time. Adverse events and reasons for changing or ceasing medications were also analysed. Results55% (74/133) adult and 46% (55/119) paediatric patients were treated with CFTR modulators. FEV1 increased in adults treated with ivacaftor (IVA) and elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) by 4.73% and 10.07% respectively, and BMI also improved in these groups. Nutrition improved in adults and children treated with lumacaftor/ivacaftor (LUM/IVA). There was no significant improvement in FEV1 or admission days with LUM/IVA or tezacaftor/ivacaftor (TEZ/IVA). 36% (31/85) ceased LUM/IVA, due to adverse effects in 81% (25/31). Of these, 92% (23/25) changed to TEZ/IVA, 78% (18/23) without significant adverse effects. ConclusionsOur findings for LUM/IVA and TEZ/IVA are less encouraging than those seen in clinical trials, with no significant improvement in lung function or admission days and a higher rate of adverse effects with LUM/IVA compared with phase 3 clinical trials. TEZ/IVA was generally well tolerated by those who experienced side effects with LUM/IVA. The small number of patients treated with ELX/TEZ/IVA had improvements in all parameters. These findings support ongoing use of IVA for individuals with gating mutations, and transition to ELX/TEZ/IVA once available for patients with at least one Phe508del mutation.

Advanced Cystic Fibrosis Lung Disease and Lung Transplantation in the Era of Cystic Fibrosis Transmembrane Conductance Regulator Modulators.

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have changed the clinical landscape of cystic fibrosis (CF) by improving clinically significant outcome measures and quality of life of people with CF (pwCF). There are now long-term data showing improved 5-year survival with the use of ivacaftor, and the field continues to evolve at a rapid pace with the continued development of highly effective CFTR modulators. While the randomized controlled trials of CFTR modulators excluded patients with severe lung disease (forced expiratory volume in 1 second <40% predicted), observational data based on case reports and registry data show similar benefits in those with advanced lung disease. This has altered clinical practice particularly as it pertains to the role of lung transplantation in CF. This article describes the impact of highly effective modulator therapy (HEMT) on the natural history of CF and the influence on the timing of referral and consideration of listing for lung transplantation. CF clinicians play a pivotal role to ensure that the impetus of the CF foundation consensus guidelines to facilitate timely referral for lung transplantation is not lost among the excitement of anticipated sustained benefit from HEMT. While the widespread availability of elexacaftor/tezacaftor/ivacaftor over the past 2 years has been associated with a sharp drop in the number of people referred for consideration for lung transplantation and the number of people wait-listed for lung transplantation, it is difficult to accurately determine the true impact due to the confounding effect of the coronavirus disease 2019 pandemic. It is expected that lung transplantation will remain an important treatment for a smaller number of pwCF. Lung transplantation offers survival benefits in CF, and there remains an imperative to ensure timely consideration of lung transplantation in patients with advanced disease to further reduce the number of pwCF dying without consideration of lung transplant.

Frequency of CFTR variants in southern Brazil and indication for modulators therapy in patients with cystic fibrosis.

This is a descriptive cross-sectional study that aims to determine the distribution of the CFTR causing variant in a group of patients at a cystic fibrosis (CF) center in southern Brazil, as well as to describe causing variants that are treatable with mutation-specific drugs. Ninety-two patients from a CF reference center were assessed in this research, all of them with a clinical diagnosis of CF and both alleles identified with pathogenic variants. The most prevalent causing variants were F508del, R1162X, G542X, and N1303K. As for patients with a mutation-specific drug indication, 69.6 % were candidates for the use of Elexacaftor/Tezacaftor/Ivacaftor (Trikafta®), 44.6 % for the use of Tezacaftor/Ivacaftor (Symdeko ®), and 35.9 % for the use of Lumacaftor/Ivacaftor (Orkambi®). For the use of Ivacaftor (Kalydeco®), only two patients (2.2 %) were candidates following the Brazilian agency approval. According to the FDA, 10 patients would be candidates for Ivacaftor (10.9 %). Causing variants of classes I and II, which are related to a major severity of the illness, were identified in 135 of 184 alleles (73.3 %). In this study, more than 2/3 of the patients were candidates for the use of CFTR modulators therapy.

Real-World Outcomes of Ivacaftor Treatment in People with Cystic Fibrosis: A Systematic Review.

Cystic fibrosis (CF) is a rare, progressive, multi-organ genetic disease. Ivacaftor, a small-molecule CF transmembrane conductance regulator modulator, was the first medication to treat the underlying cause of CF. Since its approval, real-world clinical experience on the use of ivacaftor has been documented in large registries and smaller studies. Here, we systematically review data from real-world observational studies of ivacaftor treatment in people with CF (pwCF). Searches of MEDLINE and Embase identified 368 publications reporting real-world studies that enrolled six or more pwCF treated with ivacaftor published between January 2012 and September 2019. Overall, 75 publications providing data from 57 unique studies met inclusion criteria and were reviewed. Studies reporting within-group change for pwCF treated with ivacaftor consistently showed improvements in lung function, nutritional parameters, and patient-reported respiratory and sino-nasal symptoms. Benefits were evident as early as 1 month following ivacaftor initiation and were sustained over long-term follow-up. Decreases in pulmonary exacerbations, Pseudomonas aeruginosa prevalence, and healthcare resource utilization also were reported for up to 66 months following ivacaftor initiation. In studies comparing ivacaftor treatment to modulator untreated comparator groups, clinical benefits similarly were reported as were decreases in mortality, organ-transplantation, and CF-related complications. The safety profile of ivacaftor observed in these real-world studies was consistent with the well-established safety profile based on clinical trial data. Our systematic review of real-world studies shows ivacaftor treatment in pwCF results in highly consistent and sustained clinical benefit in both pulmonary and non-pulmonary outcomes across various geographies, study designs, patient characteristics, and follow-up durations, confirming and expanding upon evidence from clinical trials.

Real-world use of ivacaftor in Canada: A retrospective analysis using the Canadian Cystic Fibrosis Registry

Background: Ivacaftor is a CFTR potentiator with demonstrated efficacy in clinical trials and has been rapidly adopted within the CF community. Given the uptake of ivacaftor in eligible people, identifying a comparator group not on modulators to measure effectiveness is difficult. We evaluated health outcomes in individuals with G551D and non-G551D genotypes on ivacaftor using real-world longitudinal data. Methods: This population-based observational study compared clinical trajectories pre-post ivacaftor using the Canadian CF Registry from 2006 to 01–01 through 2018–12–31. Piece-wise linear mixed-effects models were used to compare lung function, nutritional status, pulmonary exacerbations, and Pseudomonas colonization pre- and post-ivacaftor. Multivariable models were used to adjust for confounding factors. Results: Forced expiratory volume in 1 second (FEV1) increased significantly by 5.7 percent predicted (95% confidence interval (CI) 3.9, 7.5; p<0.001) after initiation of ivacaftor. FEV1 decline rate was attenuated to -0.30% (95% CI -0.9, 0.29; p = 0.32) predicted/year post-ivacaftor, compared with -0.75% (95% CI -1.12, -0.37; p<0.001) predicted/year pre-ivacaftor, although this difference did not reach statistical significance. BMI percentiles also increased post-ivacaftor (6.57 percentiles, 95% CI 3.91, 9.24; p<0.001). Pulmonary exacerbations showed a nonsignificant reduction of 18% (RR 0.82, 95% CI 0.61, 1.11; p = 0.19) and the odds of a positive sputum culture for Pseudomonas aeruginosa decreased in the post-ivacaftor period (odds ratio 0.44, 95% CI 0.30, 0.63; p<0.001). Conclusions: This real-world, observational study demonstrated improvement in health outcomes in a broad population of people with CF. Additional studies are needed to evaluate the impact of ivacaftor on quality of life and survival.

P165 Improvement in antibiotic usage and ppFEV1 with compassionate use of elexacaftor, tezacaftor and ivacaftor (ETI) for patients with cystic fibrosis

P165 Improvement in antibiotic usage and ppFEV1 with compassionate use of elexacaftor, tezacaftor and ivacaftor (ETI) for patients with cystic fibrosis

Ivacaftor for the treatment of cystic fibrosis in children under six years of age

ABSTRACT Introduction Cystic fibrosis (CF) results from aberrant ion transport due to abnormalities or absence of the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride transporter that resides on the apical surface of epithelial cells. A novel class of medications, known as CFTR modulators, specifically target the abnormal protein. Areas covered Ivacaftor increases the open probability of CFTR located on the cell surface, leading to enhanced chloride transport, and has been shown to improve lung function, weight, and quality of life. We reviewed the sentinel studies that lead to the approval of the use of ivacaftor in people with CF age six months and older with at least one CFTR gene mutation that is responsive to ivacaftor based on clinical trial and/or in vitro data. Children with CF have the greatest potential to benefit from CFTR modulator therapy when it is initiated prior to the development of permanent damage; however, challenges remain regarding use of ivacaftor in the youngest pediatric population. Expert opinion Ivacaftor is safe and effective CFTR modulator that can be prescribed in children over six months of age with at least one CFTR gene mutation that is responsive to ivacaftor.

The Extrapulmonary Effects of Cystic Fibrosis Transmembrane Conductance Regulator Modulators in Cystic Fibrosis.

The effects of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) modulators on lung function, pulmonary exacerbations, and quality of life have been well documented. However, CF is a multiorgan disease, and therefore an evidence base is emerging on the systemic effects of CFTR modulators beyond the pulmonary system. This is of great clinical importance, as many of these studies provide proof of concept that CFTR modulators might be used one day to prevent or treat extrapulmonary manifestations stemming from CFTR dysfunction. In this concise review of the literature, we summarize the results of key publications that have evaluated the effects of CFTR modulators on weight and growth, pancreatic function, the gastrointestinal and hepatobiliary systems, sinus disease, bone disease, exercise tolerance, fertility, mental health, and immunity. Although many of these studies have reported beneficial extrapulmonary effects related to the use of ivacaftor (IVA) in patients with CF with at least one gating mutation, most of the evidence is low or very low quality, given the limited number of patients evaluated and the lack of control groups. Based on an even smaller number of studies evaluating the extrapulmonary effects of lumacaftor-IVA, the benefits are less clear. Although limited, these studies may provide the basis for future clinical trials to evaluate CFTR modulators on the extrapulmonary manifestations of CF.

P253 Use of ivacaftor (IVA) in patients heterozygous for R117H mutation: real-life experience in a large UK adult CF centre

P253 Use of ivacaftor (IVA) in patients heterozygous for R117H mutation: real-life experience in a large UK adult CF centre

Use of ivacaftor in late diagnosed cystic fibrosis monozygotic twins heterozygous for F508del and R117H-7T \u2013 a case report

BackgroundCFTR modulator therapy with ivacaftor is a treatment option for Cystic Fibrosis (CF) patients with at least one copy of a R117H-7T mutation in the CFTR gene. Desirable effects of this therapy are improvement of lung function, decrease in exacerbation rate, normalization or reduction of sweat chloride and weight gain. Monogenetic CF-twins carry identical genetic information, so therapy response and side effects are expected to be nearly identical under this specific therapy.Case presentationIn monozygotic twins, at the age of 55, two pathogenic variants in the CFTR gene (F508del and R117H-7T) were detected. Both patients presented with a borderline sweat test (30–59 mmol/L) and despite the same genetic information and similar life circumstances the disease proceeds completely different. While one patient has severe pulmonary involvement with chronic P. aeruginosa infection, her twin sister is almost unimpaired. Liver or pancreatic involvement was not seen in either patient. Due to the presence of one copy of a R117H-7T mutation, CFTR modulator therapy with ivacaftor was initiated in both. Response and side effects were significantly different. In the less affected patient, we observed an improvement in lung function and a normalization of sweat chloride. In the severely affected patient, no functional response to treatment was seen, but stabilization of the disease state with a decrease in exacerbation and hospitalization rate and weight gain as well as a normalization of sweat chloride. There was an increase in liver enzymes in the less affected patient, which normalized after halving the dose of ivacaftor, while the therapeutic effect was maintained.ConclusionsDespite nearly identical genetic information, as in monogenetic twins, therapy response and onset of side effects of CFTR modulating therapy are very different. In patients with late diagnosis and severe pulmonary involvement, ivacaftor does not seem to improve lung function, whereas in patients with late diagnosis and low disease severity a relevant therapy response was obtained. In addition to lung function, additional clinical parameters such as reduction of exacerbation and hospitalization rate and weight gain should be used to assess therapy response, especially in severely affected patients.

Potentiators (specific therapies for class III and IV mutations) for cystic fibrosis.

Potentiators (specific therapies for class III and IV mutations) for cystic fibrosis.

Effectiveness of ivacaftor in cystic fibrosis patients with non-G551D gating mutations

BackgroundThe cystic fibrosis transmembrane conductance regulator (CFTR) potentiator ivacaftor is approved for patients with CF with gating and residual function CFTR mutations. We report the results of an observational study investigating its effects in CF patients with non-G551D gating mutations. MethodsPatients with non-G551D gating mutations were recruited to an open-label study evaluating ivacaftor. Primary outcomes included: lung function, sweat chloride, weight gain, and quality of life scores. ResultsTwenty-one subjects were enrolled and completed 6 months follow-up on ivacaftor; mean age was 25.6 years with 52% <18. Baseline ppFEV1 was 68% and mean sweat chloride 89.6 mEq/L. Participants experienced significant improvements in ppFEV1 (mean absolute increase of 10.9% 95% CI = [2.6,19.3], p = 0.0134), sweat chloride (−48.6 95% CI = [−67.4,-29.9], p < 0.0001), and weight (5.1 kg, 95% CI = [2.8, 7.3], p = 0.0002). ConclusionsPatients with non-G551D gating mutations experienced improved lung function, nutritional status, and quality of life. This study supports ongoing use of ivacaftor for patients with these mutations.

Reduction of Recurrence Risk of Pancreatitis in Cystic Fibrosis With Ivacaftor: Case Series.

The effect of ivacaftor in patients with cystic fibrosis (CF) with recurrent pancreatitis is unknown. We conducted a multicenter retrospective study of patients with CF taking ivacaftor who had a history of recurrent pancreatitis. During the first 3 months of therapy, only 1 of the 6 patients had an episode of pancreatitis, which was managed on an outpatient basis. Between 3 and 12 months on ivacaftor therapy, none of the patients had recurrence of pancreatitis or required hospitalization. The use of ivacaftor was associated with a reduced frequency and recurrence rate of pancreatitis in patients with CF.

The U.S. Food and Drug Administration's Experience with Ivacaftor in Cystic Fibrosis. Establishing Efficacy Using In Vitro Data in Lieu of a Clinical Trial.

On May 17, 2017, the U.S. Food and Drug Administration expanded the patient population for use of ivacaftor to include patients with cystic fibrosis with relatively rare mutations in the cystic fibrosis transmembrane conductance regulator gene. The label expansion is unique in that clinical efficacy was not based on clinical data but on in vitro assay data demonstrating increased chloride ion transport across cells in response to ivacaftor. Such an approach provides a pathway for adding difficult-to-study mutation-based cystic fibrosis subpopulations to the indication as well as defining mutations unresponsive to ivacaftor and has important implications for cystic fibrosis drug development and other rare genetic diseases whose genetics and disease pathophysiology are well understood.

Ivacaftor restores CFTR-dependent sweat gland fluid secretion in cystic fibrosis subjects with S945L alleles

BackgroundTo determine in vivo effects of CFTR modulators on mutation S945L. MethodsWe measured effects of CFTR modulators on CFTR-dependent sweating (‘C-sweat’) in two pancreatic sufficient cystic fibrosis (CF) subjects. S1 (S945L/G542X) took ivacaftor and S2 (S945L/F508del) took ivacaftor+tezacaftor. Sweating was stimulated pharmacologically to produce sequentially both CFTR-independent (methacholine stimulated) M-sweat and C-sweat; and the ratio of these was compared. Sweat secretion was measured with two methods: real time secretory rate quantitative recording and by optically measuring the growth of sweat bubbles under oil from multiple identified glands. ResultsUsing the quantitative recorder, we saw zero C-sweat secretion off-drug, but when on-drug the C-sweat responses for both subjects were comparable to those seen in carriers. The on-drug response was further quantified using the sweat bubble method. Each subject again showed robust C-sweat responses, with C-sweat/M-sweat ratios~half of the ratio determined for a cohort of 40 controls tested under identical conditions. ConclusionThese in vivo results, consistent with prior in vitro findings, indicate that the drug treatments restore near-normal function to S945L-CFTR, and support the use of ivacaftor as a treatment for CF patients who carry this allele.

Treatment of Cystic Fibrosis with CFTR Modulators

Personalized medicine promises that medical decisions, practices and products are tailored to the individual patient. Cystic fibrosis, an inherited disorder of chloride and bicarbonate transport in exocrine glands, is the first successful example of customized drug development for mutation-specific therapy. There are two classes of CFTR modulators: potentiators that increase the activity of CFTR at the cell surface, and correctors that either promote the read-through of nonsense mutations or facilitate the translation, folding, maturation and trafficking of mutant CFTR to the cell surface. The potentiator ivacaftor and the corrector lumacaftor are approved in Germany for the treatment of people with cystic fibrosis who carry a gating mutation such as p.Gly551Asp or who are homozygous for the most common mutation p.Phe508del, respectively. This report provides an overview of the basic defect in cystic fibrosis, the population genetics of CFTR mutations in Germany and the bioassays to assess CFTR function in humans together with the major achievements of preclinical research and clinical trials to bring CFTR modulators to the clinic. Some practical information on the use of ivacaftor and lumacaftor in daily practice and an update on pitfalls, challenges and novel strategies of bench-to-bedside development of CFTR modulators are also provided.

320 The use of ivacaftor in CF mutations with residual functioning protein

Objectives Ivacaftor was shown to decrease FEV1 by 5% in patients with classIV R117H mutation. We report the use of ivacaftor in four CF adults with various Class IV mutations. Methods Ivacaftor was prescribed to 4 patients with deteriorating clinical status. We obtained pre and post administration FEV1, weight, sweat chloride (in 3/4), and CFQ-R. Results Patient 1, a 26yo woman, CF genotype of 2 class IV mutations (R347P & L1065P). She had four pulmonary exacerbations, FEV1 dropped from 85% to 75%. Six months following ivacaftor, FEV1 improved to 81%. She gained 10 lbs. Sweat chloride decreased from 96 to 86 mmol/L and CFQ-R increased from 55 to 100. Discontinuation of ivacaftor showed marked worsening in all parameters. Patient 2 is a 61yo male with W1282X and the class IV mutation D1152H. Six months into ivacaftor, FEV1 improved from 67% to 87% and he gained 17 lbs. Sweat chloride decreased from 30 to 22 mmol/L and CFQ-R improved from 55 to 100 points. Patient 3 is a 35yo male with the class IV D579G mutation and S912X. After ivacaftor, FEV1 improved from 27% to 31%. He gained 7 lbs. Sweat chloride decreased from 91 to 74 mmol/L and CFQ-R doubled. Patient 4 is a 72yo male with CF genotype G542X and the class IV mutation D1152H. Following ivacaftor, FEV1 improved from 39% to 51%. He gained 7 lbs and CFQ-R doubled. Conclusion We noted improvement in all patients and in all parameters at 6 months compared to baseline. One patient was retested at one month after stopping ivacaftor with worsening parameters. These data support the beneficial effects of CFTR potentiators in CF mutations producing residual functioning protein.

Potentiators (specific therapies for class III and IV mutations) for cystic fibrosis.

Potentiators (specific therapies for class III and IV mutations) for cystic fibrosis.

P102 Sweat chloride is not a useful marker of clinical response to Ivacaftor

Introduction and ObjectivesThe development of the targeted CFTR potentiator Ivacaftor has significantly altered the landscape for cystic fibrosis (CF) therapeutics, and heralds the arrival of personalised medicine in this condition....

Ivacaftor: A Review of Its Use in Patients with Cystic Fibrosis

Ivacaftor (Kalydeco™) is a potentiator of the cystic fibrosis transmembrane conductance regulator (CFTR) and is the first drug that treats an underlying cause of cystic fibrosis to be licensed for use. Ivacaftor increases the open probability (i.e. gating) of CFTR channels with the G551D mutation, thus enhancing chloride transport, and is indicated in a number of countries for the treatment of cystic fibrosis in patients aged ≥6years who carry this mutation. This review focuses on pharmacological, clinical efficacy and tolerability data relevant to the use of ivacaftor in this indication. In two 48-week, double-blind, phase III trials in patients aged ≥12 (STRIVE) or 6-11 (ENVISION) years with cystic fibrosis and the G551D mutation, oral ivacaftor 150mg every 12h significantly improved lung function relative to placebo, when used in combination with standard care. Significant improvements in pulmonary exacerbation risk (in STRIVE) as well as bodyweight and some aspects of health-related quality of life (both studies) were also seen with the drug versus placebo. Moreover, the beneficial effects of ivacaftor on parameters such as lung function and bodyweight were maintained over up to 96weeks of treatment in an ongoing open-label extension of these studies. Ivacaftor was generally well tolerated, with headache, oropharyngeal pain, upper respiratory tract infection and nasal congestion being among the most common adverse events. Thus, ivacaftor expands the current treatment options for patients with cystic fibrosis who have the G551D mutation. Its potential for use in patients with other CFTR mutations is also of interest.