CFTR Modulator Therapy with Lumacaftor/Ivacaftor Alters Plasma Concentrations of Lipid-Soluble Vitamins A and E in Patients with Cystic Fibrosis

Vitamin D status and variable responses to supplements depend in part on genetic factors in adults with cystic fibrosis

Vitamin D sufficiency has been difficult to achieve consistently in patients with cystic fibrosis (CF), even with robust oral supplements. To assess vitamin D status and resistance to supplementation, we studied 80 adults using 25-hydroxyvitamin D (25OHD) determinations and whole genome sequencing to construct polygenic risk scores (PRS) that aggregate variants associated with vitamin D status. The results revealed that 30 % of patients were below the threshold of 30 ng/mL and thus should be regarded as insufficient despite normal vitamin E status, a reflection of adherence to fat soluble vitamin supplementation. The PRS values were significantly correlated with 25OHD concentrations, confirming our results in children with CF, and indicating that genetic factors play a role and have implications for therapy.

Impaired intestinal free fatty acid transport followed by chylomicron malformation, not pancreatic insufficiency, cause metabolic defects in cystic fibrosis

Intestinal disease is one of the earliest manifestations of cystic fibrosis (CF) in children and is closely tied to deficits in growth and nutrition, both of which are directly linked to future mortality. Patients are treated aggressively with pancreatic enzyme replacement therapy and a high-fat diet to circumvent fat malabsorption, but this does not reverse growth and nutritional defects. We hypothesized that defects in chylomicron production could explain why CF body weights and nutrition are so resistant to clinical treatments. We used gold standard intestinal lipid absorption and metabolism approaches, including mouse mesenteric lymph cannulation, in vivo chylomicron secretion kinetics, transmission electron microscopy, small intestinal organoids, and chylomicron metabolism assays to test this hypothesis. In mice expressing the G542X mutation in cystic fibrosis transmembrane conductance regulator (CFTR-/- mice), we find that defective FFA trafficking across the epithelium into enterocytes drives a chylomicron formation defect. Furthermore, G542X mice secrete small, triglyceride-poor chylomicrons into the lymph and blood. These defective chylomicrons are cleared into extraintestinal tissues at ∼10-fold faster than WT chylomicrons. This defect in FFA absorption resulting in dysfunctional chylomicrons cannot be explained by steatorrhea or pancreatic insufficiency and is maintained in primary small intestinal organoids treated with micellar lipids. These studies suggest that the ultrahigh-fat diet that most people with CF are counselled to follow may instead make steatorrhea and malabsorption defects worse by overloading the absorptive capacity of the CF small intestine.

Evolution of nutritional management in children with cystic fibrosis - a narrative review

Nutrition has played a central role in the management and outcomes of people with cystic fibrosis (pwCF) since the 1970s. Advances in therapies and practices in recent decades have led to a significant change in the patient landscape with dramatic improvements in life expectancy, as well as quality of life, bringing with it new issues. Historically, cystic fibrosis was a condition associated with childhood and malnutrition; however, changes in patient demographics, nutritional assessment and fundamental nutritional management have evolved, and it has become an increasingly prevalent adult disease with new nutritional challenges, including obesity. This paper aims to describe these changes and the impact and challenges they bring for those working in this field. Nutritional professionals will need to evolve, adapt and remain agile to the wider range of situations and support required for a new generation of pwCF. Specialised nutrition support will continue to be required, and it will be additionally important to improve and optimise quality of life and long-term health.

Changes in vitamins and trace elements after initiation of highly effective CFTR modulator therapy in children and adults with cystic fibrosis - a real-life insight

BACKGROUND

Highly-effective CFTR-modulator therapy with elexa-/teza-/ivacaftor (ETI) has led to improvements in pulmonary outcomes, sweat chloride, body mass index (BMI) and quality of life in people with cystic fibrosis (CF). Improved uptake of fat-soluble vitamins and micronutrients has been reported for CFTR-modulators but data regarding ETI therapy is lacking.

METHODS

This single-center retrospective study evaluated forced expiratory volume in one second (FEV-1), sweat chloride, BMI, transaminases (AST, ALT), bilirubin, vitamins A, D, E, zinc and selenium in children and adults eligible for ETI. Parameters were assessed before and up to one year after initiation of ETI.

RESULTS

58 patients (median age m = 28 years, SD ± 11.6 years, 51.7% female14 < 18 years old) were included. FEV-1 and sweat chloride improved significantly after ETI. There were no changes in BMI or AST. ALT was increased significantly after 4 weeks of ETI but returned to normal levels in further course. Bilirubin levels remained elevated after ETI. Vitamin A was significantly higher 12 months after ETI. No changes were found for vitamins D, E, zinc and selenium.

CONCLUSIONS

This study adds to the evidence that improvements of some fat-soluble vitamin levels can be found after ETI. No changes regarding micronutrients were noted. Individualized follow-up and supplementation are recommended.

Impact of elexacaftor/tezacaftor/ivacaftor on lipid and fat-soluble vitamin levels and association with body mass index

INTRODUCTION

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators improve gastrointestinal absorption of nutrients and may result in changes in body mass index (BMI), serum lipids, and fat-soluble vitamin levels. We hypothesized that serum lipids and vitamin levels would increase with CFTR modulator therapy and that greater increase in lipids and vitamin levels would be related to greater increase in BMI.

METHODS

A retrospective study was performed to evaluate the impact of elexacaftor/tezacaftor/ivacaftor (ETI) on nutritional parameters, serum lipids, and fat-soluble vitamin levels. Pre-ETI values (<2 years prior) and post-ETI values (>1 month after) were compared. Linear regression was used to evaluate whether change in BMI is associated with the change in lipid and/or vitamin levels and whether modulator duration is associated with the degree of rise in lipid and/or vitamin levels.

RESULTS

Adults and adolescents with CF (n = 137) were evaluated before and 31-300 days after starting ETI. Median BMI (adults 21.9 vs. 23.5 kg/m2 ; adolescents 48 vs. 63 percentile) increased after initiation of ETI. Total cholesterol (126 vs. 154 mg/dL), low-density lipoprotein cholesterol (63 vs. 78 mg/dL), non-high-density lipoprotein cholesterol (84 vs. 102 mg/dL), and high density lipoprotein cholesterol (43 vs. 49 mg/dL) increased after ETI, while triglycerides and very low density lipoprotein did not change. Median values for vitamin D (34.5 vs. 38.0 ng/mL) and vitamin A (40.1 vs. 47.9 µg/dL) increased, while vitamin E did not change significantly. There was no significant correlation between BMI change or duration of modulator therapy with vitamin levels or lipid changes.

CONCLUSION

After initiation of ETI therapy, serum lipids increased in our population, but most values remained within the normal range. Vitamins A and D levels increased post-ETI and no changes were noted in vitamin E. No significant correlation between the degree of BMI change and the magnitude of increase in lipids or vitamin levels was found.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

Evaluation of the efficiency of nanomicellar formulation of fat-soluble vitamins in patients with cystic fibrosis: the study protocol for a randomized controlled trial

BACKGROUND

Cystic fibrosis is an inherited disease, which is caused by the CFTR protein defects due to mutations in the CFTR gene. Along with CFTR dysfunction, exocrine pancreatic insufficiency plays a key role in persistent fat malabsorption in CF patients; therefore, deficiency of fat-soluble vitamins (A, D, E, and K) is still a therapeutic challenge. Even with efficient pancreatic enzyme medication and CF-specific vitamins, many patients with CF have fat-soluble vitamins deficiency. The present study aims to evaluate the efficiency of nanomicelle formulation of fat-soluble vitamins in children with CF in order to achieve the appropriate serum levels of these vitamins.

METHODS

This prospective, single-blind control trial will be conducted at the Akbar Children's Hospital in Mashhad, Iran. Patients with CF will be enrolled based on the eligibility criteria. The control group will receive the standard formulation of fat-soluble vitamins similar to the routine CF treatment, and for the intervention group, the nanomicelle formulation of fat-soluble vitamins will be administered for 3 months. The primary outcome of this study is the measurement of serum levels of fat-soluble vitamins. The secondary outcomes are clinical assessment by the Shwachman-Kulczycki score, anthropometrics, and quality of life. Outcomes will be assessed before and after 3 months.

DISCUSSION

Due to persistent fat-soluble vitamin deficiency in CF disease, the nanomicelle formulation could be proposed as a new delivery method of fat-soluble vitamins in the treatment of cystic fibrosis.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20220415054541N1. Registered on July 23, 2022.

Trials and tribulations of highly effective modulator therapies in cystic fibrosis

Highly effective modulator therapies (HEMTs) have revolutionised the management approach of most patients living with cystic fibrosis (CF) who have access to these therapies. Clinical trials have reported significant improvements across multiorgan systems, with patients surviving longer. However, there are accumulating case reports and observational data describing various adverse events following initiation of HEMTs including drug-to-drug interactions, drug induced liver injury, Stevens-Johnson syndrome, and neurocognitive symptoms including psychosis and depression, which have required discontinuation of therapy. Current clinical trials are assessing efficacy in younger patients with CF, yet long-term studies are also required to better understand the safety profile in the real-world setting across all ages and the impact of HEMT dose alteration or discontinuation.

The impact of elexacaftor/tezacaftor/ivacaftor on fat-soluble vitamin levels in people with cystic fibrosis

BACKGROUND

While elexacaftor/tezacaftor/ivacaftor (ETI) has improved the pulmonary health of many people with cystic fibrosis (PwCF), less is known about ETI effectiveness for extra-pulmonary manifestations, including fat-soluble vitamin malabsorption. This study aims to evaluate ETI's impact on vitamin A, D, E, and international normalized ratio (INR, an indirect marker for Vitamin K) serum levels.

METHODS

Retrospective cohort study of PwCF ≥12 years receiving ETI. Vitamin levels up to four years preceding and up to two years following ETI initiation were collected. Pairwise comparisons of vitamin levels pre/post-ETI initiation were made using Wilcoxon signed rank and McNemar's tests. Linear mixed effect models were used to regress vitamin levels on time since starting ETI, ETI use (yes/no), the interaction between time and ETI use, and age.

RESULTS

Two hundred and sixty-four participants met study inclusion, and 169 (64%) had post-ETI initiation vitamin levels. Median vitamin A levels increased from 422.0 to 471.0 mcg/L (p < 0.001), median vitamin D levels increased from 28.5 to 30.8 ng/mL (p = 0.003), and there were no significant changes in median vitamin E or INR. Vitamin A levels rose at a rate of 40.7 mcg/L/year (CI 11.3, 70.2) after ETI start.

CONCLUSIONS

ETI initiation is associated with increased median vitamin A and vitamin D levels, but no change in median vitamin E or INR levels. Ongoing monitoring of vitamin levels after ETI initiation is needed to screen for potential deficiencies and toxicities, particularly in light of case reports of hypervitaminosis A following ETI initiation.

Nutritional management of people living with cystic fibrosis throughout life and disease continuum: Changing times, new challenges

Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene encoding for the ion channel cystic fibrosis transmembrane conductance regulator (CFTR). The management of CF disease has evolved in recent decades from treating downstream disease manifestations affecting the airways, the lungs and the gastrointestinal system to addressing the CFTR gene defect. The advent of CFTR modulators, which correct the functionality of the defective CFTR, contributes to reshaping the landscape of CF demographics, prognosis and therapies, including nutritional management. A spectrum of clinical manifestations is emerging within the same patient population where undernutrition and nutritional deficiencies coexist with excessive weight gain and metabolic derangements. Such contrasting presentations challenge current practices, require adjustments to traditional approaches, and involve more individualised interventions. This narrative review examines the current state of knowledge on the nutritional management of people living with cystic fibrosis from early life to adulthood in the era of CFTR modulation.

Impact of elexacaftor/tezacaftor/ivacaftor on fat-soluble vitamin levels in children with cystic fibrosis

BACKGROUND

Children with cystic fibrosis are at risk of fat-soluble vitamin deficiency. CFTR modulators positively effect nutritional status. This study aimed to assess changes in serum vitamins A, D & E after starting ETI therapy to ensure levels were not abnormally high.

METHODS

Retrospective review of annual assessment data over 3½ years, before and after starting ETI in a specialist paediatric CF centre, including vitamin levels.

RESULTS

54 eligible patients were included, aged 5-15 yrs (median age 11.5). Median time to post measurements was 171 days. Median vitamin A was increased (1.38 to 1.63 µmol/L, p<0.001). Three patients (6%) had high vitamin A post-ETI, compared with none at baseline; and 2 (4%) had low levels compared to 4 (8%) at baseline. No changes in vitamins D&E.

CONCLUSIONS

This study found increased vitamin A, sometimes to high levels. We recommend testing levels within 3 months of starting ETI.

Evolving Nutritional Needs in Cystic Fibrosis

The course of cystic fibrosis (CF) as a nutritional illness is diverging since the introduction of highly effective modulator therapy, leading to more heterogeneous phenotypes of the disease despite CF genetic mutations that portend worse prognosis. This may become more evident as we follow the pediatric CF population into adulthood as some highly effective modulator therapies (HEMT) are approved for those as young as 1 year old. This review will outline the current research and knowledge available in the evolving nutritional health of people with CF as it relates to the impact of HEMT on anthropometrics, body composition, and energy expenditure, exocrine and endocrine pancreatic insufficiencies (the latter resulting in CF-related diabetes), vitamin and mineral deficiencies, and nutritional health in CF as it relates to pregnancy and lung transplantation.

Nutritional Status and Circulating Levels of Fat-Soluble Vitamins in Cystic Fibrosis Patients: A Cohort Study and Evaluation of the Effect of CFTR Modulators

BACKGROUND

Improved therapy in CF has led to an overall improvement in nutritional status. The objectives of our study are: to cross-sectionally assess nutritional status and serum levels of fat-soluble vitamins; to retrospectively evaluate the efficacy of modulators on nutritional status and fat-soluble vitamin levels.

METHODS

In patients younger than 2 years of age, we evaluated growth, in patients aged 2-18 years, we assessed BMI z-scores, and in adults, we assessed absolute BMI values. Levels of 25(OH)D, vitamins A, and E were measured.

RESULTS

A cross-sectional analysis was conducted on 318 patients, 109 (34.3%) with pancreatic sufficiency. Only three patients were under 2 years old. In 135 patients aged 2-18 years, the median BMI z-score was 0.11, and 5 (3.7%) patients had malnutrition (z-score ≤ 2SD). In 180 adults, the median BMI was 21.8 kg/m². Overall, 15 (13.7%) males (M) and 18 (25.3%) females (F) were underweight (18 < BMI > 20); 3 (2.7%) M and 5 (7.0%) F had a BMI < 18. Suboptimal 25(OH)D levels were found in patients with pancreatic insufficiency. The prevalence of deficiency of vitamins A and E is low. After one year of treatment with modulators, the increase in BMI was more consistent (M: 1.58 ± 1.25 kg/m² F: 1.77 ± 1.21 kg/m²) in elexacaftor/tezacaftor/ivacaftor (ETI)-treated patients compared with other modulators, with a significant increase in levels of all fat-soluble vitamins.

CONCLUSIONS

Malnutrition is present in a limited number of subjects. The prevalence of subjects with suboptimal 25(OH)D levels is high. ETI showed a beneficial effect on nutritional status and circulating levels of fat-soluble vitamins.

Nutritional Care in Children with Cystic Fibrosis

Patients with cystic fibrosis (CF) are prone to malnutrition and growth failure, mostly due to malabsorption caused by the derangement in the chloride transport across epithelial surfaces. Thus, optimal nutritional care and support should be an integral part of the management of the disease, with the aim of ameliorating clinical outcomes and life expectancy. In this report, we analyzed the nutrition support across the different ages, in patients with CF, with a focus on the relationships with growth, nutritional status, disease outcomes and the use of the CF transmembrane conductance regulator (CFTR) modulators. The nutrition support goal in CF care should begin as early as possible after diagnosis and include the achievement of an optimal nutritional status to support the growth stages and puberty development in children, that will further support the maintenance of an optimal nutritional status in adult life. The cornerstone of nutrition in patients with CF is a high calorie, high-fat diet, in conjunction with a better control of malabsorption due to pancreatic enzyme replacement therapy, and attention to the adequate supplementation of fat-soluble vitamins. When the oral caloric intake is not enough for reaching the anthropometric nutritional goals, supplemental enteral feeding should be initiated to improve growth and the nutritional status. In the last decade, the therapeutic possibilities towards CF have grown in a consistent way. The positive effects of CFTR modulators on nutritional status mainly consist in the improvement in weight gain and BMI, both in children and adults, and in an amelioration in terms of the pulmonary function and reduction of exacerbations. Several challenges need to be overcome with the development of new drugs, to transform CF from a fatal disease to a treatable chronic disease with specialized multidisciplinary care.

Nutritional impact of CFTR modulators in children with cystic fibrosis

Background

Nutritional status is a major prognostic factor for breathing and the survival of patients with cystic fibrosis (CF). Since 2012, the development of CFTR modulators has considerably transformed the outcome of this disease. Indeed, both lung function and body mass index are improved by CFTR modulators, such as Lumacaftor/Ivacaftor. However, few data exist regarding the outcome of nutritional intakes under Lumacaftor/Ivacaftor.

Methods

We conducted a prospective single-center study in children with CF treated with Lumacaftor/Ivacaftor to evaluate their nutritional intake before and after treatment.

Results

Thirty-four children were included in this study, with a median age of 12.4 years [11.9; 14.7]. There was no significant improvement in weight, height or BMI. Patients' total energy intake was not significantly changed with Lumacaftor/Ivacaftor, while carbohydrate intakes decreased significantly. We found that blood levels of vitamin E and Selenium were significantly increased under Lumacaftor/Ivacaftor, without a significant increase in supplementation. In patients with a BMI Z-score < 0 at treatment initiation, there was a significant improvement in weight and BMI Z-score, while TEI and carbohydrate intakes were significantly lower.

Conclusion

We showed that treatment with Lumacaftor/Ivacaftor improved the nutritional status of patients without necessarily being associated with an increase in nutritional intake. Although these data need to be confirmed in larger cohorts, they support the hypothesis that weight gain under modulators is multifactorial, and may be related to a decrease in energy expenditure or an improvement in absorption.

Cystic Fibrosis Patients with F508del/Minimal Function Genotype: Laboratory and Nutritional Evaluations after One Year of Elexacaftor/Tezacaftor/Ivacaftor Treatment

The last ten years have been characterized by an enormous step forward in the therapy and management of patients with Cystic Fibrosis (CF), thanks to the development and combination of Cystic Fibrosis Transmembrane Receptor (CFTR) correctors and potentiators. Specifically, the last approved triple combination elexacaftor/tezacaftor/ivacaftor has been demonstrated to improve lung function in CF patients with both homozygous Phe508del and Phe508del/minimal function genotypes. Here we have assessed the effect of elexacaftor/tezacaftor/ivacaftor in patients carrying the Phe508del/minimal function genotype (n = 20) after one year of treatments on liver function and nutrient absorption with a focus on lipid metabolism. We show that weight, BMI, and albumin significantly increase, suggesting a positive impact of the treatment on nutrient absorption. Furthermore, cholesterol levels as a biomarker of lipid metabolism increased significantly after one year of treatment. Most importantly, we suggest that these results were not dependent on the diet composition, possibly indicating that the drug improves the hepatic synthesis and secretion of proteins and cholesterol.

Nutritional and metabolic management for cystic fibrosis in a post-cystic fibrosis transmembrane conductance modulator era

PURPOSE OF REVIEW

The introduction of highly effective cystic fibrosis transmembrane conductance regulator modulators has resulted in a paradigm shift towards treating underlying cause of cystic fibrosis (CF) rather than the ensuing complications. In this review, we will describe the impact of these small molecules on growth, nutrition, and metabolic status in people with CF (pwCF).

RECENT FINDING

Results of clinical trials and real world data demonstrate that these small molecules are having a significant impact of on augmenting body weight, improving nutritional status and reducing gastrointestinal symptom burden. Early treatment can also positively impact on pancreatic endocrine and exocrine function.

SUMMARY

Nutritional and metabolic management of pwCF needs to change in order to maximize long term health and avoid future complications relating to obesity and increased cardiovascular risk. Longitudinal registry studies will be key to improve our understanding of the longer-term outcome of these new therapies.

Update on the management of vitamins and minerals in cystic fibrosis

Advancements in respiratory and nutrition management have significantly improved the survival of patients with cystic fibrosis (CF). With the availability of several nutrition interventions such as oral/enteral nutrition supplements, enteric‐coated pancreatic enzymes, and water‐miscible CF‐specific vitamin supplements, frank vitamin deficiencies—with the exception of vitamin D—are rarely encountered in current clinical practice. Whereas they were previously considered as micronutrients, our current understanding of fat‐soluble vitamins and minerals as antioxidants, immunomodulators, and disease biomarkers has been evolving. The impact of highly effective modulators on the micronutrient status of patients with CF remains elusive. This narrative review focuses on the updates on the management of fat‐soluble vitamins and other micronutrients in CF in the current era and identifies the gaps in our knowledge.

Cystic fibrosis year in review 2021

People with cystic fibrosis (CF) have an amazing outlook with the treatment availability of highly effective modulators. Unfortunately, not all people with CF are eligible for modulators leading to continued pulmonary exacerbations and advanced lung disease. Additionally, optimizing diagnosis and evaluation for CF in the newborn period continues to be an area of focus for research. This review article will work to cover articles published in 2021 with high clinical relevance related to the above topics; however, due to the extensive body of research published, this review will not be comprehensive.

Might Routine Vitamin A Monitoring in Cystic Fibrosis Patients Reduce Virus-Mediated Lung Pathology?

Cystic fibrosis (CF) is an autosomal recessive gene disorder that affects tens of thousands of patients worldwide. Individuals with CF often succumb to progressive lung disease and respiratory failure following recurrent infections with bacteria. Viral infections can also damage the lungs and heighten the CF patient's susceptibility to bacterial infections and long-term sequelae. Vitamin A is a key nutrient important for immune health and epithelial cell integrity, but there is currently no consensus as to whether vitamin A should be monitored in CF patients. Here we evaluate previous literature and present results from a CF mouse model, showing that oral vitamin A supplements significantly reduce lung lesions that would otherwise persist for 5-6 weeks post-virus exposure. Based on these results, we encourage continued research and suggest that programs for the routine monitoring and regulation of vitamin A levels may help reduce virus-induced lung pathology in CF patients.