Gilbert's syndrome leads to elevated bilirubin after initiation of elexacaftor/tezacaftor/ivacaftor in people with cystic fibrosis.

Nine people with cystic fibrosis (pwCF) were found to have isolated elevations in serum total bilirubin after starting elexacaftor/tezacaftor/ivacaftor (ETI) that were associated with Gilbert's Syndrome. In longitudinal examination, total bilirubin levels increased substantially after initiation of ETI without elevations in liver transaminases in those with this syndrome. Because elevated bilirubin levels in Gilbert's Syndrome are benign, ETI was able to be continued in these individuals. Genetic testing for this relatively common syndrome should be strongly considered for pwCF experiencing isolated hyperbilirubinemia after starting ETI, since appropriate diagnosis may help pwCF avoid unnecessary interruption in this therapy with significant health benefits in CF.

Cystic fibrosis airway inflammation enables elexacaftor/tezacaftor/ivacaftor-mediated rescue of N1303K CFTR mutation.

Rescue of N1303K CFTR by highly effective modulator therapy (HEMT) is enabled by CF airway inflammation. These findings suggest that evaluation of HEMT for rare CFTR mutations must be performed under inflammatory conditions relevant to CF airways. https://bit.ly/3tTcoJE.

Changes in fecal elastase-1 following initiation of CFTR modulator therapy in pediatric patients with cystic fibrosis.

BACKGROUND: Improvement in exocrine pancreatic function in persons with CF (pwCF) on cystic fibrosis transmembrane conductance regulator (CFTR) modulators has been documented in clinical trials using fecal pancreatic elastase-1 (FE-1). Our group endeavored to evaluate real-world data on FE-1 in children on CFTR modulator therapy at three pediatric cystic fibrosis (CF) centers. METHODS: Pediatric pwCF were offered FE-1 testing if they were on pancreatic enzyme replacement therapy (PERT) and on CFTR modulator therapy according to their center's guideline. FE-1 data were collected retrospectively. The primary outcome was absolute change in FE-1. RESULTS: 70 pwCF were included for analysis. 53 had baseline and post-modulator FE-1 values. There was a significant increase in FE-1 from median 25 mcg/g (IQR 25-60) at baseline to 57 mcg/g (IQR 20-228) post-modulator (p<0.001 by Wilcoxon matched pairs), with an absolute change in FE-1 of median 28 mcg/g (IQR -5-161) and mean 93.5 ± 146.8 mcg/g. Age was negatively correlated with change in FE-1 (Spearman r=-0.48, p<0.001). 15 pwCF (21%) had post-modulator FE-1 values ≥200 mcg/g, consistent with pancreatic sufficiency (PS). The PS group was significant for younger age at initiation of first CFTR modulator and a higher baseline FE-1. CONCLUSIONS: Most pwCF experienced an increase in FE-1 while receiving CFTR modulator treatment and a small percentage demonstrated values reflective of PS. These data suggest that PS may be attained in those that initiated modulator therapy at a younger age or had a higher baseline FE-1. FE-1 testing is suggested for children on any CFTR modulator therapy.

Population Pharmacokinetics of Posaconazole in Immune-Compromised Children and Assessment of Target Attainment in Invasive Fungal Disease.

BACKGROUND AND OBJECTIVE: Posaconazole (PSZ) is a triazole antifungal for the management of invasive fungal disease (IFD) in adults and children. Although PSZ is available as an intravenous (IV) solution, oral suspension (OS) and delayed-release tablets (DRTs), OS is the preferred formulation for pediatric use because of potential safety concerns associated with an excipient in the IV formulation and difficulty in swallowing intact tablets by children. However, poor biopharmaceutical characteristics of the OS formulation leads to an unpredictable dose-exposure profile of PSZ in children, potentially risking therapeutic failure. The goal of this study was to characterize the population pharmacokinetics (PK) of PSZ in immunocompromised children and assess therapeutic target attainment. METHODS: Serum concentrations of PSZ were collected retrospectively from records of hospitalized patients. A population PK analysis was performed in a nonlinear mixed-effects modeling framework with NONMEM (v7.4). The PK parameters were scaled to body weight, then potential covariate effects were assessed. The final PK model was used to evaluate recommended dosing schemes through simulation of target attainment (as a percentage of the population having steady-state trough concentrations above the recommended target) using Simulx (v2021R1). RESULTS: Repeated measurement data of 202 serum concentrations of total PSZ were acquired from 47 immunocompromised patients between 1 and 21 years of age receiving PSZ either intravenously or orally, or both. A one-compartment PK model with first-order absorption and linear elimination best fit the data. The estimated absolute bioavailability (95% confidence interval) for suspension (Fs) was 16% (8-27%), which was significantly lower than the reported tablet bioavailability (Ft) [67%]. Fs was reduced by 62% and 75% upon concomitant administration with pantoprazole (PAN) and omeprazole (OME), respectively. Famotidine resulted in a reduction of Fs by only 22%. Both fixed dosing and weight-based adaptive dosing provided adequate target attainment when PAN or OME were not coadministered with the suspension. CONCLUSIONS: The results of this study revealed that both fixed and weight-based adaptive dosing schemes can be appropriate for target attainment across all PSZ formulations, including suspension. Additionally, covariate analysis suggests that concomitant proton pump inhibitors should be contraindicated during PSZ suspension dosing.

Building a pediatric rare lung disease program: It takes a community of villages.

Pediatric rare lung disease programs are increasing in number due to an increase in recognition of the diseases, increased clinical and research interest in children's interstitial lung disease, and the expansion of the children's interstitial lung disease research network. Due to this increased interest newly graduated trainees in pediatric pulmonology and other physicians are often starting new programs, which can be daunting. We provide some guidance for new programs based on our experiences.

Outcomes of Children with Fetal and Lactation Immunosuppression Exposure Born to Female Transplant Recipients.

Solid organ transplantation (SOT) is a lifesaving procedure for those with end-stage kidney, liver, heart, lung, and intestinal diseases, including females of childbearing age who wish to proceed with pregnancy following transplantation. While there is clear risk associated with use of mycophenolate during pregnancy, the risks associated with use of other immunosuppressant agents are less well understood, and the timing of use in pregnancy may be pertinent when considering the risk versus benefit for individual patients. In addition to overall fetal outcomes, including gestational age, birth weight, and mortality, this review summarizes published literature on additional complications that have been examined in association with maternal use during pregnancy and postpartum while breastfeeding. Compared with non-transplant pregnancies, pregnancies in transplant recipients are associated with lower birth weight and earlier gestational age. Effects associated with particular immunosuppressant agents in the infant include renal dysfunction from calcineurin inhibitors, myelosuppression from azathioprine, and decreased circulating immune cells with several agents. However, these effects are noted to primarily be transient, though the decrease in immune cells may predispose the infant to increased infectious complications in the first year of life. Utilizing relative infant dose estimations, nearly all commonly utilized immunosuppressants are likely safe during breastfeeding given the limited exposure to the infant.

Poor tolerability of cystic fibrosis transmembrane conductance regulator modulator therapy in lung transplant recipients.

Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) is a highly effective therapy for patients with cystic fibrosis (CF) with potential benefits in lung transplant recipients (LTRs) for extrapulmonary CF manifestations; however, tolerability and efficacy in this population are largely unknown. We report our experience with ELX/TEZ/IVA in LTRs for extrapulmonary complications of CF including tolerability, drug-drug interactions, and therapeutic benefit. All LTRs at a single center initiated on ELX/TEZ/IVA were reviewed. Adverse events and patient-reported outcomes attributed to ELX/TEZ/IVA were documented. Pulmonary function, tacrolimus requirements in mg/kg/dl, body mass index (BMI), and reason for initiation were assessed at the initiation of ELX/TEZ/IVA, and at 12 months post-initiation or at the time of discontinuation for those in whom therapy was discontinued. Thirteen LTRs were initiated on ELX/TEZ/IVA at a mean of 115 ± 92 months post-transplant. All were initiated on ELX/TEZ/IVA for sinus or sinus and gastrointestinal CF manifestations. Five (38.4%) patients discontinued therapy due to declining pulmonary function (2/5, 40%), mood disturbances (2/5, 40%), or lack of benefit (1/5, 20%). Of the eight patients who remain on ELX/TEZ/IVA, four reported adverse effects and three LTRs temporarily held therapy. Six (46.2%) LTRs reported improvement in sinus symptoms, while four (30.7%) reported improved gastrointestinal symptoms. Weight declined in the cohort overall. Tacrolimus dose requirements decreased following initiation of ELX/TEZ/IVA therapy, with a 50% decline in dose requirements observed. In our experience, ELX/TEZ/IVA in LTRs is poorly tolerated with modest perceived extrapulmonary benefit and a significant effect on tacrolimus dose requirements. More data are needed to determine the benefits of ELX/TEZ/IVA therapy in LTRs.

Pharmacist-administered audiology screening for pediatric cystic fibrosis patients exposed to high-dose aminoglycosides: A pilot study.

This pilot study successfully implemented a standardized protocol for tablet-based ototoxicity screening in pediatric cystic fibrosis (CF) patients exposed to aminoglycosides. Further studies are needed to assess the impact of implementation in a larger number of patients, as well as to determine barriers that may exist at centers with variation in available resources. This method of ototoxicity screening represents an accessible alternative to traditional audiology testing, and given the continued improvements in expected life span for people with CF, it is imperative that patients have regular access to this type of screening to allow for early identification of medication-related toxicities.

Cystic Fibrosis Foundation otolaryngology care multidisciplinary consensus recommendations.

BACKGROUND: Cystic fibrosis (CF) is a multisystem disease that often requires otolaryngology care. Individuals with CF commonly have chronic rhinosinusitis but also present with hearing loss and dysphonia. Given these manifestations of CF, otolaryngologists are frequently involved in the care of patients with CF; however, there is limited consensus on optimal management of sinonasal, otologic, and laryngologic symptoms. METHODS: The Cystic Fibrosis Foundation convened a multidisciplinary team of otolaryngologists, pulmonologists, audiologists, pharmacists, a social worker, a nurse coordinator, a respiratory therapist, two adults with CF, and a caregiver of a child with CF to develop consensus recommendations. Workgroups developed draft recommendation statements based on a systematic literature review, and a ≥80% consensus was required for acceptance of each recommendation statement. RESULTS: The committee voted on 25 statements. Eleven statements were adopted recommending a treatment or intervention, while five statements were formulated recommending against a specific treatment or intervention. The committee recommended eight statements as an option for select patients in certain circumstances, and one statement did not reach consensus. CONCLUSION: These multidisciplinary consensus recommendations will help providers navigate decisions related to otolaryngology consultation, medical and surgical management of CF-CRS, hearing, and voice in individuals with CF. A collaborative and multidisciplinary approach is advocated to best care for our patients with CF. Future clinical research is needed utilizing standardized, validated outcomes with comprehensive reporting of patient outcome, effects of modulator therapies, and genetic characteristics to help continue to advance care, decrease morbidity, and improve the quality of life for individuals with CF.

The role of a pharmacy residency program in global health: Establishing pediatric clinical pharmacy services in a Malawian hospital.

PURPOSE: To describe the establishment of pediatric clinical pharmacy services in a Malawian hospital as part of a pharmacy residency program's engagement in global health. SUMMARY: While pharmacy is expanding its role in global health through the introduction of international advanced pharmacy practice experience (APPE) rotations at US schools of pharmacy, international experiences for pharmacy residents are currently very limited. Such programs are advantageous for pharmacists planning for a career in public or global health, and there is also great opportunity for clinical pharmacists to work with international partners for professional development and to help advance pharmacy practice. The University of North Carolina at Chapel Hill Eshelman School of Pharmacy recently expanded its international APPE rotation in Malawi into the postgraduate training space through creation of a pediatric pharmacy residency training program, with the specific aim of working with partners in Malawi to introduce pediatric pharmacy services at Kamuzu Central Hospital. As this was the first time there was a pharmacist involved in patient care on the pediatric wards, the focus for the participating pharmacy resident was on establishing a positive relationship with the medical team through providing high-quality collaborative patient care for the pediatric population. In addition to working to establish pediatric clinical pharmacy services, the resident further contributed to sustainable improvements in pediatric patient care by identifying areas for quality improvement. We discuss several considerations for the successful implementation of international experiences and their impact on participating residents. CONCLUSION: Pharmacy has an opportunity to build on the success of international APPE rotations and expand postgraduate offerings. Through collaboration with other institutions already involved in global health and identifying international rotation sites, residency programs across the country can create similarly beneficial global health experiences for their pharmacy residents.

Evaluation of Posaconazole Dosing in Children and Young Adults: A Single-Center Review.

OBJECTIVE: Initial posaconazole dosing regimens in children often do not achieve target concentrations, and data continue to support the need for higher initial dosing regimens. The objective of this study is to contribute to the current data regarding suboptimal posaconazole dosing in pediatric patients by retrospectively observing dosing strategies and subsequent drug concentrations. METHODS: This study was conducted at a single institution in 27 patients aged 1 to 21 years. Patients who were initiated on any formulation of posaconazole for prophylaxis or treatment while admitted to the hospital were included. The primary outcome was to determine the percentage of pediatric patients who achieved the targeted trough concentration using their initial posaconazole dosing regimen. Secondary outcomes included percentage of patients who experienced a breakthrough invasive fungal infection (IFI), percentage of patients with elevated liver function tests (LFTs), and discontinuation for any reason. RESULTS: There were 15 patients (55.5%) who reached desired trough serum concentration after the initial dosing regimen. The number of dose modifications to achieve the desired trough ranged from 1 to 3. Most patients received delayed-release tablets (n = 17), and the average doses for reaching prophylactic and treatment trough concentrations were 6.1 mg/kg/day and 11 mg/kg/day, respectively. There were 2 patients (7.4%) who experienced breakthrough IFI. Overall, 5 patients developed elevated LFTs and 7 patients discontinued treatment early. CONCLUSIONS: The results describe a single population of pediatric patients, of whom 55% were able to achieve target trough concentrations of posaconazole with the initial dosing strategy used.

Association of Medication Regimen Complexity With Clinical Endpoints in Pediatric Patients With Cystic Fibrosis.

OBJECTIVE: Cystic fibrosis (CF) patients and caregivers are impacted by the number of pharmacological agents and unique administration needs; however, no data currently assesses how medication regimen complexity impacts clinical outcomes in this population. The objective of this study is to evaluate if an association exists between increased medication regimen complexity and clinical endpoints in pediatric patients with CF. METHODS: This retrospective analysis included all pediatric patients with CF (ages 5-20 years) with at least 2 pharmacist encounters and acceptable pulmonary function tests at our pediatric pulmonary clinic during 2017. Each patient's medication regimen was scored using the validated Medication Regimen Complexity Index (MRCI) tool. The primary outcome was the correlation between MRCI score and lung function. Secondary endpoints included growth, number of infections requiring antibiotics, and hospitalizations. RESULTS: MRCI scores of the 113 included patients ranged from 2 to 101 points. A negative correlation was found between initial and final MRCI score and initial and final forced expiratory volume in 1 second (FEV1; r = -0.323, p = 0.0005 and r = -0.287, p = 0.0021, respectively). MRCI scores were negatively correlated with BMI percentile for both encounters (r = -0.162 and r = -0.125) but were not significant. Higher MRCI scores were associated with increased use of oral and intravenous antibiotics and hospital admissions. CONCLUSIONS: Higher MRCI scores are correlated with a significant decrease in FEV1, increased need for antibiotic therapy, and more hospital admissions in pediatric patients with CF. Larger studies are needed to determine if a correlation exists between MRCI score and growth.

Cost-effectiveness of implementing routine hearing screening using a tablet audiometer for pediatric cystic fibrosis patients receiving high-dose IV aminoglycosides.

BACKGROUND: Cystic fibrosis (CF) patients who receive high-dose aminoglycosides can acquire inner ear damage and subsequent hearing loss. There is no current standard protocol for assessing ototoxicity in CF centers in the United States. OBJECTIVE: To evaluate the cost-effectiveness of a pharmacist-implemented routine hearing screening for ototoxicity among pediatric patients using a clinically validated tablet audiometer to allow for earlier detection of hearing loss in an exploratory analysis. METHODS: A Markov decision-analytic model was developed to assess the cost-effectiveness of implementing routine screening with monthly cycles over a 3-year time horizon. The model measured the difference in promptly detected hearing loss, delayed detected hearing loss, and undetected hearing loss, compared with current screening practices. Model inputs were obtained through a comprehensive literature review. Primary model outcomes included total health care costs and quality-adjusted life-years (QALYs) gained with a 3% yearly discount. One-way, two-way, and probabilistic sensitivity analyses were conducted to evaluate model uncertainty. RESULTS: In a hypothetical cohort of 100 patients, routine screening using a tablet audiometer increased promptly detected hearing loss by 8 patients. There was an incremental gain of 3.2 QALYs at an increased cost of $333,826 compared with current screening practices. This resulted in an incremental cost-effectiveness ratio (ICER) of $103,771 per QALY. In the 1-way sensitivity analysis, the ICER ranged between $64,345 and $258,830 per QALY. CONCLUSIONS: Using a tablet audiometer for routine hearing screening appears to be a cost-effective option at a $150,000 per QALY willingness-to-pay threshold when only considering the immediate benefits gained. This analysis did not examine the long-term effects of early detection in language development for pediatric patients. DISCLOSURES: Huang reports funding from the University of North Carolina and GlaxoSmithKline Health Outcomes Fellowship. GlaxoSmithKline had no involvement in the study creation, analysis, or manuscript composition. The other authors have nothing to disclose.