Optimizing nasal potential difference analysis for CFTR modulator development: assessment of ivacaftor in CF subjects with the G551D-CFTR mutation.

Nasal potential difference (NPD) is used as a biomarker of the cystic fibrosis transmembrane conductance regulator (CFTR) and epithelial sodium channel (ENaC) activity. We evaluated methods to detect changes in chloride and sodium transport by NPD based on a secondary analysis of a Phase II CFTR-modulator study. Thirty-nine subjects with CF who also had the G551D-CFTR mutation were randomized to receive ivacaftor (Kalydeco™; also known as VX-770) in four doses or placebo twice daily for at least 14 days. All data were analyzed by a single investigator who was blinded to treatment assignment. We compared three analysis methods to determine the best approach to quantify changes in chloride and sodium transport: (1) the average of both nostrils; (2) the most-polarized nostril at each visit; and (3) the most-polarized nostril at screening carried forward. Parameters of ion transport included the PD change with zero chloride plus isoproterenol (CFTR activity), the basal PD, Ringer's PD, and change in PD with amiloride (measurements of ENaC activity), and the delta NPD (measuring CFTR and ENaC activity). The average and most-polarized nostril at each visit were most sensitive to changes in chloride and sodium transport, whereas the most-polarized nostril at screening carried forward was less discriminatory. Based on our findings, NPD studies should assess both nostrils rather than a single nostril. We also found that changes in CFTR activity were more readily detected than changes in ENaC activity, and that rigorous standardization was associated with relatively good within-subject reproducibility in placebo-treated subjects (± 2.8 mV). Therefore, we have confirmed an assay of reasonable reproducibility for detecting chloride-transport improvements in response to CFTR modulation.

Tolerability of curcumin in pediatric inflammatory bowel disease: a forced-dose titration study.

BACKGROUND: Inflammatory bowel disease (IBD) is characterized by chronic intestinal inflammation in the absence of a recognized etiology. The primary therapies are medications that possess anti-inflammatory or immunosuppressive effects. Given the high use of complementary alternative medicines in pediatric IBD, a prospective tolerability study of curcumin, an herbal therapy with known anti-inflammatory effects, was conducted to assess possible dosage in children with IBD. METHODS: Prospectively, patients with Crohn disease or ulcerative colitis in remission or with mild disease (Pediatric Crohn's Disease Activity Index [PCDAI] <30 or Pediatric Ulcerative Colitis Activity Index [PUCAI] score <34) were enrolled in a tolerability study. All patients received curcumin in addition to their standard therapy. Patients initially received 500 mg twice per day for 3 weeks. Using the forced-dose titration design, doses were increased up to 1 g twice per day at week 3 for a total of 3 weeks and then titrated again to 2 g twice per day at week 6 for 3 weeks. Validated measures of disease activity, using the PUCAI and PCDAI, and the Monitoring of Side Effect System score were obtained at weeks 3, 6, and 9. RESULTS: All patients tolerated curcumin well, with the only symptom that was consistently reported during all 3 visits being an increase in gassiness, which occurred in only 2 patients. Three patients saw improvement in PUCAI/PCDAI score. CONCLUSIONS: This pilot study suggests that curcumin may be used as an adjunctive therapy for individuals seeking a combination of conventional medicine and alternative medicine.

Botulinum toxin for spasticity in children with cerebral palsy: a comprehensive evaluation.

BACKGROUND: Spasticity is a prevalent disabling clinical symptom for children with cerebral palsy. Treatment of spasticity with botulinum toxin in children with cerebral palsy was first reported in 1993. Botulinum toxin provides a focal, controlled muscle weakness with reduction in spasticity. Interpretation of the literature is difficult because of the paucity of reliable measures of spasticity and challenges with measuring meaningful functional changes in children with disabilities. OBJECTIVE: This study documents the effects of botulinum toxin A injections into the gastrocnemius muscles in children with spastic diplegia. Outcomes are evaluated across all 5 domains of the National Centers for Medical and Rehabilitation Research domains of medical rehabilitation. METHODS: A randomized, double-masked, placebo-controlled design was applied to 33 children with spastic diplegia with a mean age of 5.5 and Gross Motor Function Classification System Levels of I through III. Participants received either 12 U/kg botulinum toxin A or placebo saline injections to bilateral gastrocnemius muscles. Outcomes were measured at baseline and 3, 8, 12, and 24 weeks after injection. RESULTS: Significant decreases in the electromyographic representation of spasticity were documented 3 weeks after botulinum toxin A treatment. A significant decrease in viscoelastic aspects of spasticity was present at 8 weeks, and subsequent increases in dorsiflexion range were documented at 12 weeks for the botulinum toxin A group. Improvement was found in performance goals at 12 weeks and in maximum voluntary torque and gross motor function at 24 weeks for the botulinum toxin A. There were no significant differences between groups in satisfaction with performance goals, energy expenditure, Ashworth scores, or frequency of adverse effects. CONCLUSIONS: The safety profile of 12 U/kg of botulinum toxin A is excellent. Although physiologic and mechanical effects of treatment with botulinum toxin A were documented with functional improvement at 6 months, family satisfaction with outcomes were no different. Communication is needed to ensure realistic expectations of treatment.

Coefficients of fat and nitrogen absorption in healthy subjects and individuals with cystic fibrosis.

BACKGROUND: We sought to compare the differences of coefficient of fat absorption (CFA) and coefficient of nitrogen absorption (CNA) in healthy individuals and those with cystic fibrosis (CF) and to study the precision of CFA and CNA. METHODS: Sixteen healthy and 23 subjects with CF and pancreatic insufficiency ate a high-fat, high-protein diet for 72 hours; stool was collected between blue food dye markers to determine CFA and CNA. Subjects with CF withheld pancreatic enzymes. Tests were repeated on 5 of the CF and 10 of the healthy subjects. RESULTS: In healthy subjects, mean CFA was 93.5% ± 2.7%; mean CNA was 88.1% ± 5%. Median test-retest in 10 healthy subjects was +0.7% CFA (range, -8.1% to + 5.9%) and +0.9% CNA (range, -14.6% to +6.8%). For subjects with CF, mean CFA was 38.5% ± 14.7% and mean CNA was 52.2% ± 11.4%. Median test-retest change in 5 subjects with CF was -6.9% CFA (range, -19.7% to +42.8%) and +14.7% CNA (range, -6.4% to +42.8%). CONCLUSIONS: CFA and CNA have inconsistent precision in CF. The limitations of CFA as a measure of steatorrhea correction in CF should be recognized in studies of pancreatic enzyme supplements.

Microbiology, safety, and pharmacokinetics of aztreonam lysinate for inhalation in patients with cystic fibrosis.

BACKGROUND: Aztreonam lysinate for inhalation (AI) is a novel monobactam formulation being investigated for pulmonary Pseudomonas aeruginosa infections in patients with cystic fibrosis (CF). METHODS: Pre-clinical studies investigated the pre- and post-nebulization activity of AI and its activity in the presence of CF sputum. A double-blind, placebo-controlled, dose-escalation trial determined pharmacokinetics and tolerability of AI in subjects with CF. Single daily escalating doses of AI 75, 150, or 225 mg, or placebo were self-administered using an eFlow Electronic Nebulizer. Sputum samples were collected up to 4 hr and blood samples up to 8 hr post-dose. RESULTS: AI activity against multiple CF isolates was retained after nebulization via eFlow, and activity was not inhibited by CF sputum. All 12 adult subjects and 11/12 adolescents tolerated all AI doses. One patient had an asymptomatic FEV1 decrease > 20% with the 150 mg dose. Median aztreonam sputum concentrations in adults 10 min after AI 75, 150, and 225 mg were 383, 879, and 985 microg/g, respectively. Median sputum concentrations in adolescents 10 min after AI 75, 150, and 225 mg were 324, 387, and 260 microg/g, respectively. Systemic exposure to AI was low. Plasma pharmacokinetics in adults receiving AI 75 mg were Cmax = 419 ng/g, Tmax = 0.99 hr, t1/2 = 2.1 hr. Aztreonam concentrations in sputum were at or above the MIC50 for at least 4 hr post-dose. CONCLUSION: These data support the continued development of AI for treatment of pulmonary infections in patients with CF.

A randomized, clinical trial of oral midazolam plus placebo versus oral midazolam plus oral transmucosal fentanyl for sedation during laceration repair.

OBJECTIVE: To determine whether a combination of oral transmucosal fentanyl (Fentanyl Oralet, Abbott Laboratories, North Chicago, IL) plus oral midazolam has an acceptable safety profile and is more effective than oral midazolam alone for sedation during laceration repair in a pediatric emergency department (ED). METHODS: Randomized, double-blind, placebo-controlled, clinical trial. Patients between 2 and 8 years of age who weighed >10 kg and presented to the ED with a laceration in need of repair under sedation were eligible for inclusion. All patients received oral midazolam (0.5 mg/kg; maximum dose 10 mg) and either fentanyl (5-10 microg/kg) or placebo in oralet form. Data collected every 5 minutes included the following: heart rate, oxygen saturation, respiratory rate, pain as measured on a Children's Hospital of Eastern Ontario Pain Score (CHEOPS) scale (range: 4-13), and an activity scale (range: 1-5). Effectiveness of sedation was measured by CHEOPS and activity scores compared between the treatment groups. RESULTS: Fifty-one patients were randomized to receive oral midazolam plus fentanyl (N = 28) or oral midazolam plus placebo (N = 23). Age, weight, gender, or baseline pain and activity scores did not differ between the 2 groups. Seven patients in the fentanyl group vomited compared with 0 patients in the placebo group. Three patients in the fentanyl group and no patients in the placebo group had brief oxygen saturation below 93% on room air. The mean pain score within 5 minutes of the start of the procedure did not differ between the 2 groups (fentanyl group, 9.4 versus placebo group, 8.8). Mean activity scores within 5 minutes of the start of the procedure were also similar (fentanyl group, 4.3 versus placebo group, 4.3). CONCLUSIONS: The addition of oral transmucosal fentanyl to oral midazolam did not improve pain or activity scores in pediatric patients given sedation for laceration repair. Patients who received Fentanyl Oralet suffered significantly more side effects despite the relatively low doses administered in this study. Oral transmucosal fentanyl should not be used for procedural sedation in the ED.