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.

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.

Limited effects of azithromycin on the oropharyngeal microbiome in children with CF and early pseudomonas infection.

BACKGROUND: Tobramycin inhalation solution (TIS) and chronic azithromycin (AZ) have known clinical benefits for children with CF, likely due to antimicrobial and anti-inflammatory activity. The effects of chronic AZ in combination with TIS on the airway microbiome have not been extensively investigated. Oropharyngeal swab samples were collected in the OPTIMIZE multicenter, randomized, placebo-controlled trial examining the addition of AZ to TIS in 198 children with CF and early P. aeruginosa infection. Bacterial small subunit rRNA gene community profiles were determined. The effects of TIS and AZ were assessed on oropharyngeal microbial diversity and composition to uncover whether effects on the bacterial community may be a mechanism of action related to the observed changes in clinical outcomes. RESULTS: Substantial changes in bacterial communities (total bacterial load, diversity and relative abundance of specific taxa) were observed by week 3 of TIS treatment for both the AZ and placebo groups. On average, these shifts were due to changes in non-traditional CF taxa that were not sustained at the later study visits (weeks 13 and 26). Bacterial community measures did not differ between the AZ and placebo groups. CONCLUSIONS: This study provides further evidence that the mechanism for AZ's effect on clinical outcomes is not due solely to action on airway microbial composition.

Cystic Fibrosis: A Review.

Importance: Cystic fibrosis, a genetic disorder defined by variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, affects more than 30 000 individuals in the US and approximately 89 000 worldwide. Absent or decreased function of the CFTR protein is associated with multiorgan dysfunction and shortened life expectancy. Observations: CFTR is an anion channel in the apical membrane of epithelial cells. Loss of function leads to obstructed exocrine glands. Of people with cystic fibrosis in the US, approximately 85.5% have the gene variant F508del. Manifestations of cystic fibrosis in patients with the F508del gene variant begin in infancy with steatorrhea, poor weight gain, and respiratory symptoms (coughing, wheezing). As people with cystic fibrosis age, chronic respiratory bacterial infections cause loss of lung function and bronchiectasis. With the availability of universal newborn screening in multiple countries including the US, many people with cystic fibrosis are asymptomatic at diagnosis. With multidisciplinary care teams that included dietitians, respiratory therapists, and social workers, treatment of cystic fibrosis can slow disease progression. Median survival has improved from 36.3 years (95% CI, 35.1-37.9) in 2006 to 53.1 years (95% CI, 51.6-54.7) in 2021. Pulmonary therapies for patients with cystic fibrosis consist of mucolytics (eg, dornase alfa), anti-inflammatories (eg, azithromycin), and antibiotics (such as tobramycin delivered by a nebulizer). Four small molecular therapies, termed CFTR modulators, that facilitate CFTR production and/or function have received regulatory approval. Examples are ivacaftor and elexacaftor-tezacaftor-ivacaftor. For example, in patients with 1 F508del variant, the combination of ivacaftor, tezacaftor, and elexacaftor improved lung function from -0.2% in the placebo group to 13.6% (difference, 13.8%; 95% CI, 12.1%-15.4%) and decreased the annualized estimated rate of pulmonary exacerbations from 0.98 to 0.37 (rate ratio, 0.37; 95% CI, 0.25-0.55). Improved respiratory function and symptoms have lasted up to 144 weeks in postapproval observational studies. An additional 177 variants are eligible for treatment with the elexacaftor-tezacaftor-ivacaftor combination. Conclusion: Cystic fibrosis affects approximately 89 000 people worldwide and is associated with a spectrum of disease related to exocrine dysfunction, including chronic respiratory bacterial infections and reduced life expectancy. First-line pulmonary therapies consist of mucolytics, anti-inflammatories, and antibiotics, and approximately 90% of people with cystic fibrosis who are 2 years or older may benefit from a combination of ivacaftor, tezacaftor, and elexacaftor.

Potential implicit bias in attribution of adverse events in randomized controlled trials in cystic fibrosis.

INTRODUCTION: Although work to date in cystic fibrosis (CF) has elucidated frequencies and characteristics of adverse events, the accuracy of attribution of relatedness to study drug by investigators has not been assessed. We aimed to determine whether there was an association of attribution by group allocation in CF clinical trials. METHODS: We conducted a secondary analysis from 4 CF trials of all persons who experienced an AE. Our primary outcome was the odds of an AE related to active study drug and predictor of interest was the treatment allocation. We constructed a multivariable generalized estimating equation model allowing for repeated measures. RESULTS: A total of 785 subjects (47.5% female, mean age 12 years) had 11,974 AEs, of which 430 were serious. AE attribution was greater with receipt of active study drug as compared to placebo but did not reach statistical significance (OR 1.38, 95% CI 0.98-1.82). Significantly associated factors included female sex (OR 0.58, 95% 0.39-0.87), age (OR 1.24, 95% CI 1.06-1.46) and baseline lung function (per 10%, OR 1.16, 95% CI 1.05-1.28). CONCLUSION: In our large study, there was a non-significant but greater odds of AE attribution (a key element of clinical trial reporting) to active study drug based on assigned treatment to study drug or control which suggests that there is a trend in physicians to attribute blinded safety data to the active drug. Interestingly, females were less likely to have AE attribution to study drug and warrants further work in development and validation of monitoring guidelines and processes.

Upper airway microbiota development in infants with cystic fibrosis diagnosed by newborn screen.

BACKGROUND: Changes in upper airway microbiota may impact early disease manifestations in infants with cystic fibrosis (CF). To investigate early airway microbiota, the microbiota present in the oropharynx of CF infants over the first year of life was assessed along with the relationships between microbiota and growth, antibiotic use and other clinical variables. METHODS: Oropharyngeal (OP) swabs were collected longitudinally between 1 and 12 months of age from infants diagnosed with CF by newborn screen and enrolled in the Baby Observational and Nutrition Study (BONUS). DNA extraction was performed after enzymatic digestion of OP swabs. Total bacterial load was determined by qPCR and community composition assessed using 16S rRNA gene analysis (V1/V2 region). Changes in diversity with age were evaluated using mixed models with cubic B-splines. Associations between clinical variables and bacterial taxa were determined using a canonical correlation analysis. RESULTS: 1,052 OP swabs collected from 205 infants with CF were analyzed. Most infants (77%) received at least one course of antibiotics during the study and 131 OP swabs were collected while the infant was prescribed an antibiotic. Alpha diversity increased with age and was only marginally impacted by antibiotic use. Community composition was most highly correlated with age and was only moderately correlated with antibiotic exposure, feeding method and weight z-scores. Relative abundance of Streptococcus decreased while Neisseria and other taxa increased over the first year. CONCLUSIONS: Age was more influential on the oropharyngeal microbiota of infants with CF than clinical variables including antibiotics in the first year of life.

Phase 3 Open-Label Clinical Trial of Elexacaftor/Tezacaftor/Ivacaftor in Children Aged 2-5 Years with Cystic Fibrosis and at Least One F508del Allele.

Rationale: Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) has been shown to be safe and effective in people with cystic fibrosis (CF) aged ⩾6 years with at least one F508del-CFTR allele but has not been studied in younger children. Objectives: To evaluate the safety, pharmacokinetics, pharmacodynamics, and efficacy of ELX/TEZ/IVA in children with CF aged 2-5 years. Methods: In this phase 3, open-label, two-part study (parts A and B), children weighing <14 kg (on Day 1) received ELX 80 mg once daily (qd), TEZ 40 mg qd, and IVA 60 mg each morning and 59.5 mg each evening; children weighing ⩾14 kg received ELX 100 mg qd, TEZ 50 mg qd, and IVA 75 mg every 12 hours. Measurements and Main Results: The primary endpoints for part A (15-d treatment period) were pharmacokinetics and safety and tolerability. For part B (24-wk treatment period), the primary endpoint was safety and tolerability; secondary endpoints included pharmacokinetics and absolute changes from baseline in sweat chloride concentration and lung clearance index2.5 (LCI2.5, defined as the number of lung turnovers required to reduce the end tidal N2 concentration to 2.5% of its starting value) through Week 24. Analysis of pharmacokinetic data from 18 children enrolled in part A confirmed the appropriateness of the part B dosing regimen. In part B, 75 children (F508del/minimal function genotypes, n = 52; F508del/F508del genotype, n = 23) were enrolled and dosed. Seventy-four children (98.7%) had adverse events, which were all mild (62.7%) or moderate (36.0%) in severity. The most common adverse events were cough, fever, and rhinorrhea. Decreases in sweat chloride concentration (-57.9 mmol/L; 95% confidence interval [CI], -61.3 to -54.6; n = 69) and LCI2.5 (-0.83 U; 95% CI, -1.01 to -0.66; n = 50) were observed from baseline through Week 24. Mean body mass index was within the normal range at baseline and remained stable at Week 24. Conclusions: In this open-label study in children 2-5 years of age, ELX/TEZ/IVA treatment was generally safe and well tolerated, with a safety profile consistent with that observed in older age groups, and led to clinically meaningful reductions in sweat chloride concentration and LCI2.5. Clinical trial registered with www.clinicaltrials.gov (NCT04537793).

Access to Chimeric Antigen Receptor T Cell Clinical Trials in Underrepresented Populations: A Multicenter Cohort Study of Pediatric and Young Adult Acute Lymphobastic Leukemia Patients.

Chimeric antigen receptor T cell (CAR-T) therapy is a promising approach to improve survival for children and adults with relapsed/refractory (r/r) B cell acute lymphoblastic leukemia (B-ALL), but these clinical trials might not be equally accessible to patients of low socioeconomic status (SES) or to patients from racial or ethnic minority groups. We sought to describe the sociodemographic characteristics of pediatric and adolescent and young adult (AYA) patients enrolled in CAR-T clinical trials and to compare these characteristics to those of other patients with r/r B-ALL. We conducted a multicenter retrospective cohort study at 5 pediatric consortium sites to compare the sociodemographic characteristics of patients treated and enrolled in CAR-T trials at their home institution, other patients with r/r B-ALL treated at these sites, and patients referred from an external hospital for CAR-T trials. The patients were age 0 to 27 years with r/r B-ALL treated at 1 of the consortium sites between 2012 and 2018. Clinical and demographic data were collected from the electronic health record. We calculated distance from home to treating institution and assigned SES scores based on census tract. Among the 337 patients treated for r/r B-ALL, 112 were referred from an external hospital to a consortium site and enrolled in a CAR-T trial and 225 were treated primarily at a consortium site, with 34% enrolled in a CAR-T trial. Patients treated primarily at a consortium site had similar characteristics regardless of trial enrollment. Lower proportions of Hispanic patients (37% versus 56%; P = .03), patients whose preferred language was Spanish (8% versus 22%; P = .006), and publicly insured patients (38% versus 65%; P = .001) were referred from an external hospital than were treated primarily at a consortium site and enrolled in a CAR-T trial. Patients who are Hispanic, Spanish-speaking, or publicly insured are underrepresented in referrals from external hospitals to CAR-T centers. External provider implicit bias also may influence referral of these patients. Establishing partnerships between CAR-T centers and external hospital sites may improve provider familiarity, patient referral, and patient access to CAR-T clinical trials.

Safety and efficacy of vanzacaftor-tezacaftor-deutivacaftor in adults with cystic fibrosis: randomised, double-blind, controlled, phase 2 trials.

BACKGROUND: Elexacaftor-tezacaftor-ivacaftor has been shown to be safe and efficacious in people with cystic fibrosis and at least one F508del allele. Our aim was to identify a novel cystic fibrosis transmembrane conductance regulator (CFTR) modulator combination capable of further increasing CFTR-mediated chloride transport, with the potential for once-daily dosing. METHODS: We conducted two phase 2 clinical trials to assess the safety and efficacy of a once-daily combination of vanzacaftor-tezacaftor-deutivacaftor in participants with cystic fibrosis who were aged 18 years or older. A phase 2 randomised, double-blind, active-controlled study (VX18-561-101; April 17, 2019, to Aug 20, 2020) was carried out to compare deutivacaftor monotherapy with ivacaftor monotherapy in participants with CFTR gating mutations, following a 4-week ivacaftor monotherapy run-in period. Participants were randomly assigned to receive either ivacaftor 150 mg every 12 h, deutivacaftor 25 mg once daily, deutivacaftor 50 mg once daily, deutivacaftor 150 mg once daily, or deutivacaftor 250 mg once daily in a 1:1:2:2:2 ratio. The primary endpoint was absolute change in ppFEV1 from baseline at week 12. A phase 2 randomised, double-blind, controlled, proof-of-concept study of vanzacaftor-tezacaftor-deutivacaftor (VX18-121-101; April 30, 2019, to Dec 10, 2019) was conducted in participants with cystic fibrosis and heterozygous for F508del and a minimal function mutation (F/MF genotypes) or homozygous for F508del (F/F genotype). Participants with F/MF genotypes were randomly assigned 1:2:2:1 to receive either 5 mg, 10 mg, or 20 mg of vanzacaftor in combination with tezacaftor-deutivacaftor or a triple placebo for 4 weeks, and participants with the F/F genotype were randomly assigned 2:1 to receive either vanzacaftor (20 mg)-tezacaftor-deutivacaftor or tezacaftor-ivacaftor active control for 4 weeks, following a 4-week tezacaftor-ivacaftor run-in period. Primary endpoints for part 1 and part 2 were safety and tolerability and absolute change in ppFEV1 from baseline to day 29. Secondary efficacy endpoints were absolute change from baseline at day 29 in sweat chloride concentrations and Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain score. These clinical trials are registered with ClinicalTrials.gov, NCT03911713 and NCT03912233, and are complete. FINDINGS: In study VX18-561-101, participants treated with deutivacaftor 150 mg once daily (n=23) or deutivacaftor 250 mg once daily (n=24) had mean absolute changes in ppFEV1 of 3·1 percentage points (95% CI -0·8 to 7·0) and 2·7 percentage points (-1·0 to 6·5) from baseline at week 12, respectively, versus -0·8 percentage points (-6·2 to 4·7) with ivacaftor 150 mg every 12 h (n=11); the deutivacaftor safety profile was consistent with the established safety profile of ivacaftor 150 mg every 12 h. In study VX18-121-101, participants with F/MF genotypes treated with vanzacaftor (5 mg)-tezacaftor-deutivacaftor (n=9), vanzacaftor (10 mg)-tezacaftor-deutivacaftor (n=19), vanzacaftor (20 mg)-tezacaftor-deutivacaftor (n=20), and placebo (n=10) had mean changes relative to baseline at day 29 in ppFEV1 of 4·6 percentage points (-1·3 to 10·6), 14·2 percentage points (10·0 to 18·4), 9·8 percentage points (5·7 to 13·8), and 1·9 percentage points (-4·1 to 8·0), respectively, in sweat chloride concentration of -42·8 mmol/L (-51·7 to -34·0), -45·8 mmol/L (95% CI -51·9 to -39·7), -49·5 mmol/L (-55·9 to -43·1), and 2·3 mmol/L (-7·0 to 11·6), respectively, and in CFQ-R respiratory domain score of 17·6 points (3·5 to 31·6), 21·2 points (11·9 to 30·6), 29·8 points (21·0 to 38·7), and 3·3 points (-10·1 to 16·6), respectively. Participants with the F/F genotype treated with vanzacaftor (20 mg)-tezacaftor-deutivacaftor (n=18) and tezacaftor-ivacaftor (n=10) had mean changes relative to baseline (taking tezacaftor-ivacaftor) at day 29 in ppFEV1 of 15·9 percentage points (11·3 to 20·6) and -0·1 percentage points (-6·4 to 6·1), respectively, in sweat chloride concentration of -45·5 mmol/L (-49·7 to -41·3) and -2·6 mmol/L (-8·2 to 3·1), respectively, and in CFQ-R respiratory domain score of 19·4 points (95% CI 10·5 to 28·3) and -5·0 points (-16·9 to 7·0), respectively. The most common adverse events overall were cough, increased sputum, and headache. One participant in the vanzacaftor-tezacaftor-deutivacaftor group had a serious adverse event of infective pulmonary exacerbation and another participant had a serious rash event that led to treatment discontinuation. For most participants, adverse events were mild or moderate in severity. INTERPRETATION: Once-daily dosing with vanzacaftor-tezacaftor-deutivacaftor was safe and well tolerated and improved lung function, respiratory symptoms, and CFTR function. These results support the continued investigation of vanzacaftor-tezacaftor-deutivacaftor in phase 3 clinical trials compared with elexacaftor-tezacaftor-ivacaftor. FUNDING: Vertex Pharmaceuticals.

Transforming the nutrition care model for infants with cystic fibrosis: A qualitative study of clinicians' perspectives.

Clinician perspectives may inform health service strategies to meet optimal nutrition needs for infants with cystic fibrosis (CF). We conducted a qualitative study with CF-specialized dietitians (registered dietitians [RDs]) and physicians between July to December 2020 to characterize the current state of infant nutrition care delivery and organize input into a conceptual model to inform CF care program strategies. Among 42 participants, 36 completed survey responses and 6 completed interviews; 93% were RDs. Three global themes emerged in the current care model: nutrition management, family centered connections, and collaborative care delivery. Within nutrition management, clinicians emphasized providing education, setting goals, and maintaining adequate follow-up with families. Under family centered connections, clinicians expressed the need to foster relationships with families and link families to resources for assistance to social stressors such as food insecurity. Collaborative care delivery for clinicians interviewed was defined by sharing expertise from across the interdisciplinary team. Based on the timing of this study, clinicians reported compelling examples for various modes of telehealth and home weight monitoring to facilitate and support these domains of nutrition care, including potential advantages for education, supporting family needs, and communication. We integrate these themes to propose a conceptual model to organize complementary in-person and telehealth activities and enhance quality infant CF nutrition care delivery. Future implementation can refine this model through testing of practical telehealth interventions to optimize nutrition outcomes for infants with CF.

Systemic Corticosteroids in the Management of Pediatric Cystic Fibrosis Pulmonary Exacerbations.

Rationale: Pulmonary exacerbation (PEx) events contribute to lung function decline in people with cystic fibrosis (CF). CF Foundation PEx guidelines note that a short course of systemic corticosteroids may offer benefit without contributing to long-term adverse effects. However, insufficient evidence exists to recommend systemic corticosteroids for PEx treatment. Objectives: To determine if systemic corticosteroids for the treatment of in-hospital pediatric PEx are associated with improved clinical outcomes compared with treatment without systemic corticosteroids. Methods: We conducted a retrospective cohort study using the CF Foundation Patient Registry-Pediatric Health Information System linked database. People with CF were included if hospitalized for a PEx between 2006 and 2018 and were 6-21 years of age. Time to next PEx was assessed by Cox proportional hazards regression. Lung function outcomes were assessed by linear mixed-effect modeling and generalized estimating equations. To address confounding by indication, inverse probability treatment weighting was used. Results: A total of 3,471 people with CF contributed 9,787 PEx for analysis. Systemic corticosteroids were used in 15% of all PEx. In our primary analysis, systemic corticosteroids were not associated with better pre- to post-PEx percent predicted forced expiratory volume in 1 second responses (mean difference, -0.36; 95% confidence interval [CI], -1.14, 0.42; P = 0.4) or a higher odds of returning to lung function baseline (odds ratio, 0.97; 95% CI, 0.84-1.12; P = 0.7) but were associated with a reduced chance of future PEx requiring intravenous antibiotics (hazard ratio, 0.91; 95% CI, 0.85-0.96; P = 0.002). When restricting the analysis to one PEx per person, lung function outcomes remained no different among PEx treated with or without systemic corticosteroids, but, in contrast to our primary analysis, the use of systemic corticosteroids was no longer associated with a reduced chance of having a future PEx requiring intravenous antibiotics (hazard ratio, 0.96; 95% CI, 0.86, 1.07; P = 0.42). Conclusions: Systemic corticosteroid treatment for in-hospital pediatric PEx was not associated with improved lung function outcomes. Prospective trials are needed to better evaluate the risks and benefits of systemic corticosteroid use for PEx treatment in children with CF.

Association between stool consistency and clinical variables among infants with cystic fibrosis: Findings from the BONUS study.

BACKGROUND: Concerns related to stool consistency are common in the first year of life among children with cystic fibrosis (CF). However, normal stool patterns for infants with CF have not been described. METHODS: Secondary analysis was completed from the previously described BONUS cohort which followed 231 infants with CF through the first 12 months of life. Pain, stool category, stool frequency, feeding type, PERT dose, acid suppression medication, antibiotics usage, stool softener usage and fecal calprotectin were described at 3, 6, and 12 months. Repeated measure ANOVA was used to test the difference in mean stool number. Generalized linear mixed models were used to investigate the relationship between stool characteristics and various factors. RESULTS: The frequency of constipation was stable throughout the first year of life (10-13%) while watery stool significantly decreased from 21.3% at 3 months to 5.8% at 12 months (p=<0.001). The number of stools at months 6 (mean=2.40) and 12 (mean=2.50) are significantly lower than in month 3 (mean=2.83), p<0.025. Exclusive breast feeding was associated with an increased risk for constipation (OR=2.64  [1.60-4.37], p = 0.002) while exclusive formula feeding and acid suppression was associated with decreased risk for constipation (OR=0.40  [0.26-0.61], p=<0.0001 and OR=0.59  [0.39-0.89], p = 0.01 respectively). Pain was not significantly associated with stool consistency. CONCLUSION: Stool frequency and consistency evolves in infant with CF in a fashion similar to that reported in non-CF infants over the first year. Constipation was not associated with pain and was less common among infants receiving acid suppression or exclusively formula feeding.

Impact of azithromycin on serum inflammatory markers in children with cystic fibrosis and new Pseudomonas.

Chronic azithromycin improves outcomes in cystic fibrosis (CF), but its mechanism of action is unclear. The OPTIMIZE trial demonstrated improvement in time to first pulmonary exacerbation in children with new Pseudomonas treated with azithromycin. Azithromycin effect on systemic markers of inflammation over 18 months was assessed by change from baseline for high-sensitivity C-reactive protein, myeloperoxidase, calprotectin and absolute neutrophil count in the OPTIMIZE population. Subjects treated with chronic azithromycin or placebo had samples collected at baseline, 39 and 78 weeks of treatment. In 129 subjects, a significant decrease in high-sensitivity C-reactive protein was present at 39 weeks in the azithromycin group compared to placebo, but no significant difference between the groups at 78 weeks. No differences in change from baseline in myeloperoxidase, calprotectin or absolute neutrophil count were present at either time point. This supports the concept of a transient immunomodulatory effect for chronic azithromycin therapy in children with CF.

Impact of guideline-recommended dietitian assessments on weight gain in infants with cystic fibrosis.

BACKGROUND: Cystic fibrosis (CF)-specialized nutrition care strives to meet normal infant growth, but the relationship of dietitian assessments to weight outcomes is unknown. We characterize nutrition management for inadequate weight gain and assess association of dietitian assessments and center-level weight-for-age Z-scores (WAZ). METHODS: We used encounter data from 226 infants across 28 US CF Centers from the Baby Observational Nutritional study between January 2012 through December 2017. We identified dietitian assessments and consensus guideline-recommended responses to inadequate weight gain: calorie increases, pancreatic enzyme replacement therapy (PERT) increases, or shortened time to next visit. We compared center assessments by funnel plot and summarize median WAZ by center. RESULTS: Of 2,527 visits, 808 (32%) visits had identified inadequate weight gain, distributed in 216 infants. Assessments occurred in 1953 visits (77%), but varied widely between centers (range 17% - 98%). For inadequate weight gain, most and least common responses were calorie increase (64%) and PERT increase (21%). Funnel plot analysis identified 4 high-performers for frequent dietitian assessments (range 92% - 98%) and 4 under-performers (range 17% - 56%). High-performers treated inadequate weight gain more often with adequate calories (24/30, 80% v. 12/23, 52%) and closer follow up (104/164, 63% v. 60/120, 49%) compared to under-performers. Three of 4 high-performing sites met center nutrition goals for positive median WAZ at 2 years old unlike 3 under-performers (WAZHigh 0.33 v. WAZLow -0.15), despite similar patient characteristics. CONCLUSION: We characterized multicenter variation in dietitian assessments, identifying opportunities to improve care delivery to target early nutrition outcomes.

A new path for CF clinical trials through the use of historical controls.

BACKGROUND: Given future challenges in conducting large randomized, placebo controlled trials for future CF therapeutics development, we evaluated the potential for using external historical controls to either enrich or replace traditional concurrent placebo groups in CF trials. METHODS: The study included data from sequentially completed, randomized, controlled clinical trials, EPIC and OPTIMIZE respectively, evaluating optimal antibiotic therapy to reduce the risk of pulmonary exacerbation in children with early Pseudomonas aeruginosa infection. The primary treatment effect in OPTIMIZE, the risk of pulmonary exacerbation associated with azithromycin, was re-estimated in alternative designs incorporating varying numbers of participants from the earlier trial (EPIC) as historical controls. Bias and precision of these estimates were characterized. Propensity scores were derived to adjust for baseline differences across study populations, and both Poisson and Cox regression were used to estimate treatment efficacy. RESULTS: Replacing 86 OPTIMIZE placebo participants with 304 controls from EPIC to mimic a fully historically controlled trial resulted an 8% reduction in risk of pulmonary exacerbations (Hazard ratio (HR):0.92 95% CI 0.61, 1.34) when not adjusting for key baseline differences between study populations. After adjustment, a 37% decrease in risk of exacerbation (HR:0.63, 95% CI 0.50, 0.80) was estimated, comparable to the estimate from the original trial comparing the 86 placebo participants to 77 azithromycin participants on azithromycin (45%, HR:0.55, 95% CI: 0.34, 0.86). Other adjusted approaches provided similar estimates for the efficacy of azithromycin in reducing exacerbation risk: pooling all controls from both studies provided a HR of 0.60 (95% x`CI 0.46, 0.77) and augmenting half the OPTIMIZE placebo participants with EPIC controls gave a HR 0.63 (95% CI 0.48, 0.82). CONCLUSIONS: The potential exists for future CF trials to utilize historical control data. Careful consideration of both the comparability of controls and of optimal methods can reduce the potential for biased estimation of treatment effects.

Most Short Children with Cystic Fibrosis Do Not Catch Up by Adulthood.

Poor linear growth is common in children with cystic fibrosis (CF) and predicts pulmonary status and mortality. Growth impairment develops in infancy, prior to pulmonary decline and despite aggressive nutritional measures. We hypothesized that growth restriction during early childhood in CF is associated with reduced adult height. We used the Cystic Fibrosis Foundation (CFF) patient registry to identify CF adults between 2011 and 2015 (ages 18-19 y, n = 3655) and had height for age (HFA) records between ages 2 and 4 y. We found that only 26% CF adults were ≥median HFA and 25% were <10th percentile. Between 2 and 4 years, those with height < 10th percentile had increased odds of being <10th percentile in adulthood compared to children ≥ 10th percentile (OR = 7.7). Of HFA measured between the 10th and 25th percentiles at ages 2-4, 58% were <25th percentile as adults. Only 13% between the 10th and 25th percentile HFA at age 2-4 years were >50th percentile as adults. Maximum height between ages 2 and 4 highly correlated with adult height. These results demonstrate that low early childhood CF height correlates with height in adulthood. Since linear growth correlates with lung growth, identifying both risk factors and interventions for growth failure (nutritional support, confounders of clinical care, and potential endocrine involvement) could lead to improved overall health.