Longitudinal bacterial prevalence in cystic fibrosis airways: Fact and artifact.

BACKGROUND: Opportunistic bacterial infection is a hallmark of cystic fibrosis (CF) lung disease and early mortality. Poorly characterized prevalence changes have accompanied two decades of health improvements, with CFTR modulators likely to further affect infection epidemiology. METHODS: Bacterial prevalence change trends across birth cohorts were assessed with linear regression using 2001-2019 US CF Foundation Patient Registry data. Informative missingness was assessed, as was age-to-age infection status. RESULTS: Bacterial prevalence constantly changed from 2001 to 2019, with changes differing across birth cohorts. Informative censoring affected prevalence change for some organisms. Age-to-age infection status changes were greater than net changes in bacterial prevalence and varied by age. CONCLUSIONS: CF infection epidemiology changed over two decades and will continue to do so. Understanding how modulators affect infection epidemiology will require creative designs for longitudinal prevalence change studies emphasizing prevalence changes independent of effects on lung biology.

Heterogeneity of CFTR modulator-induced sweat chloride concentrations in people with cystic fibrosis.

BACKGROUND: Sweat chloride (SC) concentrations in people with cystic fibrosis (PwCF) reflect relative CF transmembrane conductance regulator (CFTR) protein function, the primary CF defect. Populations with greater SC concentrations tend to have lesser CFTR function and more severe disease courses. CFTR modulator treatment can improve CFTR function within specific CF genotypes and is commonly associated with reduced SC concentration. However, SC concentrations do not necessarily fall to concentrations seen in the unaffected population, suggesting potential for better CFTR treatment outcomes. We characterized post-modulator SC concentration variability among CHEC-SC study participants by genotype and modulator. METHODS: PwCF receiving commercially approved modulators for ≥90 days were enrolled for a single SC measurement. Clinical data were obtained from chart review and the CF Foundation Patient Registry (CFFPR). Variability of post-modulator SC concentrations was assessed by cumulative SC concentration frequencies. RESULTS: Post-modulator SC concentrations (n = 3787) were collected from 3131 PwCF; most (n = 1769, 47 %) were collected after elexacaftor/tezacaftor/ivacaftor (ETI) treatment. Modulator use was associated with lower SC distributions, with post-ETI concentrations the lowest on average. Most post-ETI SC concentrations were <60 mmol/L (79 %); 26 % were <30 mmol/L. Post-ETI distributions varied by genotype. All genotypes containing at least one F508del allele had individuals with post-ETI SC ≥60 mmol/L, with the largest proportion being F508del/minimal function (31 %). CONCLUSIONS: Post-modulator SC concentration heterogeneity was observed among all genotypes and modulators, including ETI. The presence of PwCF with post-modulator SC concentrations within the CF diagnostic range suggests room for additional treatment-associated CFTR restoration in this population.

Phase II studies of nebulised Arikace in CF patients with Pseudomonas aeruginosa infection.

RATIONALE: Arikace is a liposomal amikacin preparation for aerosol delivery with potent Pseudomonas aeruginosa killing and prolonged lung deposition. OBJECTIVES: To examine the safety and efficacy of 28 days of once-daily Arikace in cystic fibrosis (CF) patients chronically infected with P aeruginosa. METHODS: 105 subjects were evaluated in double-blind, placebo-controlled studies. Subjects were randomised to once-daily Arikace (70, 140, 280 and 560 mg; n=7, 5, 21 and 36 subjects) or placebo (n=36) for 28 days. Primary outcomes included safety and tolerability. Secondary outcomes included lung function (forced expiratory volume at one second (FEV1)), P aeruginosa density in sputum, and the Cystic Fibrosis Quality of Life Questionnaire-Revised (CFQ-R). RESULTS: The adverse event profile was similar among Arikace and placebo subjects. The relative change in FEV1 was higher in the 560 mg dose group at day 28 (p=0.033) and at day 56 (28 days post-treatment, 0.093L±0.203 vs -0.032L±0.119; p=0.003) versus placebo. Sputum P aeruginosa density decreased >1 log in the 560 mg group versus placebo (days 14, 28 and 35; p=0.021). The Respiratory Domain of the CFQ-R increased by the Minimal Clinically Important Difference (MCID) in 67% of Arikace subjects (560 mg) versus 36% of placebo (p=0.006), and correlated with FEV1 improvements at days 14, 28 and 42 (p<0.05). An open-label extension (560 mg Arikace) for 28 days followed by 56 days off over six cycles confirmed durable improvements in lung function and sputum P aeruginosa density (n=49). CONCLUSIONS: Once-daily Arikace demonstrated acute tolerability, safety, biologic activity and efficacy in patients with CF with P aeruginosa infection.

Willingness of people with cystic fibrosis receiving elexacaftor/tezacaftor/ivacaftor (ETI) to participate in randomized modulator and inhaled antimicrobial clinical trials.

OBJECTIVE: To assess the feasibility of enrolling people with CF (pwCF) taking the CFTR modulator elexacaftor/tezacaftor/ivacaftor (ETI) in clinical trials of a new modulator. METHODS: PwCF receiving ETI at CHEC-SC study (NCT03350828) enrollment were surveyed for interest in 2-week to 6-month placebo- (PC) and active-comparator (AC) modulator studies. Those taking inhaled antimicrobials (inhABX) were surveyed for interest in PC inhABX studies. RESULTS: Of 1791 respondents, 75% [95% CI 73, 77] would enroll in a 2-week PC modulator study versus 51% [49, 54] for a 6-month study; 82% [81, 84] and 63% [61, 65] would enroll in 2-week and 6 month AC studies; 77% [74, 80] of 551 taking inhABX would enroll in a 2-week PC inhABX study versus 59% [55, 63] for a 6-month study. Previous clinical trial experience increased willingness. CONCLUSIONS: Study designs will affect feasibility of future clinical trials of new modulators and inhABX in people receiving ETI.

Characterizing CFTR modulated sweat chloride response across the cf population: Initial results from the CHEC-SC study.

BACKGROUND: CHEC-SC is an ongoing epidemiologic study characterizing modulator-induced sweat chloride (SC) responses across the CF population, with interim results available prior to the availability of triple combination modulator therapy. METHODS: Eligible participants had been prescribed a modulator for ≥90 days with re-enrollment allowed upon establishment of a new modulator. Pre-modulator SC values were obtained from chart review; post-modulator sweat was collected and analyzed locally. SC changes were descriptively summarized with biologic sex effects adjusted for age, weight, and CFTR genotype. Heterogeneity in ivacaftor SC response was characterized in relation to published CFTR functional responses. RESULTS: 1848 participants provided 2004 SC measurements, 26.2% on ivacaftor, 39.1% on lumacaftor/ivacaftor, and 34.7% on tezacaftor/ivacaftor. Average SC changes for all modulators were consistent with those reported in previous clinical studies, with greater variation in SC response observed among rarer mutations and notable shifts in the proportion with SC <60mmol/L independent of the magnitude of SC change. Ivacaftor induced in vitro CFTR functional change was significantly correlated with ivacaftor-modulated SC response (Pearson correlation= ‒0.52, 95% CI: ‒0.773, ‒0.129). Average SC change from ivacaftor to tezacaftor/ivacaftor was ‒4.9 mmol/L (n=17,95% CI:‒9.3, ‒0.5) and differed from those switching from lumacaftor/ivacaftor (10.0 mmol/L, n=139, 95% CI:7.8,12.3). Sex at birth was not associated with SC response. CONCLUSIONS: CHEC-SC is the largest study characterizing modulator-induced SC changes across the CF population. There was a strong association between ivacaftor induced in vitro CFTR function and SC response across a genotypically heterogenous cohort. Biological sex was not associated with SC response.

Efficacy and safety of ataluren in patients with nonsense-mutation cystic fibrosis not receiving chronic inhaled aminoglycosides: The international, randomized, double-blind, placebo-controlled Ataluren Confirmatory Trial in Cystic Fibrosis (ACT CF).

BACKGROUND: Ataluren was developed for potential treatment of nonsense-mutation cystic fibrosis (CF). A previous phase 3 ataluren study failed to meet its primary efficacy endpoint, but post-hoc analyses suggested that aminoglycosides may have interfered with ataluren's action. Thus, this subsequent trial (NCT02139306) was designed to assess the efficacy and safety of ataluren in patients with nonsense-mutation CF not receiving aminoglycosides. METHODS: Eligible subjects with nonsense-mutation CF (aged ≥6 years; percent predicted (pp) FEV1 ≥40 and ≤90) from 75 sites in 16 countries were randomly assigned in double-blinded fashion to receive oral ataluren or matching placebo thrice daily for 48 weeks. The primary endpoint was absolute change in average ppFEV1 from baseline to the average of Weeks 40 and 48. FINDINGS: 279 subjects were enrolled; 138 subjects in the ataluren arm and 136 in the placebo arm were evaluable for efficacy. Absolute ppFEV1 change from baseline did not differ significantly between the ataluren and placebo groups at Week 40 (-0.8 vs -1.8) or Week 48 (-1.7 vs -2.4). Average ppFEV1 treatment difference from baseline to Weeks 40 and 48 was 0.6 (95% CI -1.3, 2.5; p = 0.54). Pulmonary exacerbation rate per 48 weeks was not significantly different (ataluren 0.95 vs placebo 1.13; rate ratio p = 0.40). Safety was similar between groups. No life-threatening adverse events or deaths were reported. INTERPRETATION: Neither ppFEV1 change nor pulmonary exacerbation rate over 48 weeks were statistically different between ataluren and placebo groups. Development of a nonsense-mutation CF therapy remains elusive.

Building global development strategies for cf therapeutics during a transitional cftr modulator era.

As CFTR modulator therapy transforms the landscape of cystic fibrosis (CF) care, its lack of uniform access across the globe combined with the shift towards a new standard of care creates unique challenges for the development of future CF therapies. The advancement of a full and promising CF therapeutics pipeline remains a necessary priority to ensure maximal clinical benefits for all people with CF. It is through collaboration across the global CF community that we can optimize the evaluation and approval process of new therapies. To this end, we must identify areas for which harmonization is lacking and for which efficiencies can be gained to promote ethical, feasible, and credible study designs amidst the changing CF care landscape. This article summarizes the counsel from core advisors across multiple international regions and clinical trial networks, developed during a one-day workshop in October 2019. The goal of the workshop was to identify, in consideration of the highly transitional era of CFTR modulator availability, the drug development areas for which global alignment is currently uncertain, and paths forward that will enable advancement of CF therapeutic development.

KB001-A, a novel anti-inflammatory, found to be safe and well-tolerated in cystic fibrosis patients infected with Pseudomonas aeruginosa.

BACKGROUND: Chronic Pseudomonas aeruginosa (Pa) airways infection, exuberant local inflammation, and progressive lung function loss are hallmarks of cystic fibrosis (CF). KB001-A is an anti-PcrV PEGylated monoclonal antibody fragment to the Type III secretion system of Pa. This 16-week study evaluated KB001-A associated effect on time-to-need for antibiotics for worsening respiratory signs and symptoms, as well as safety, and treatment-associated changes in symptom scores, inflammatory markers, and spirometry. METHODS: This was a randomized, double-blind, placebo-controlled, repeat-dose study in CF subjects with Pa. Intravenous 10mg/kg KB001-A or placebo infusions were administered at baseline and weeks 2, 4, 8, and 16, with a 4-week follow-up. Sputum inflammatory markers were assessed in a sub-study. Time-to-need for antibiotics was compared between groups by Kaplan Meier analysis and Cox proportional hazards modeling adjusting for randomization strata. RESULTS: Of 182 subjects, 169 received at least one infusion of KB001-A (n=83) or placebo (n=86). KB001-A was generally safe and well-tolerated as compared to placebo, with no significant emergent adverse effects other than one serious adverse event of elevated hepatic enzymes of unclear etiology. Time to need for antibiotics did not differ between groups (HR: 1.00; 95% CI: 0.69, 1.45, p=0.995). A 3.2 increase in ppFEV1 from placebo favoring KB001-A was observed at week 16 (95% CI: 1.12, 5.30, p=0.003). Mean changes from baseline in log10 sputum neutrophil elastase (NE) had a non-significant decrease (-0.27, 95% CI: -0.58,0.04, p=0.084) while IL-8 concentrations at week 16 were significantly lower (-0.27, 95% CI: -0.55,0.00, p=0.048) among KB001-A subjects (n=16) relative to placebo (n=13). CONCLUSIONS: KB001-A was safe and well-tolerated and associated with a modest FEV1 benefit and reduction in select sputum inflammatory markers (IL-8). KB001-A was not associated with an increased time to need for antibiotics. The lack of efficacy seen with KB001-A may be due, in part, to the low levels of the type III secretion proteins previously reported in sputum of CF patients chronically infected with Pa.

Excessive inflammatory response of cystic fibrosis mice to bronchopulmonary infection with Pseudomonas aeruginosa.

In cystic fibrosis (CF), defective function of the cystic fibrosis transmembrane conductance regulator (CFTR) in airway epithelial cells and submucosal glands results in chronic pulmonary infection with Pseudomonas aeruginosa. The pulmonary infection incites an intense host inflammatory response, causing progressive suppurative pulmonary disease. Mouse models of CF, however, fail to develop pulmonary disease spontaneously. We examined the effects of bronchopulmonary infection on mice homozygous for the S489X mutation of the CFTR gene using an animal model of chronic Pseudomonas endobronchial infection. Slurries of sterile agarose beads or beads containing a clinical isolate of mucoid P. aeruginosa were instilled in the right lung of normal or CF mice. The mortality of CF mice inoculated with Pseudomonas-laden beads was significantly higher than that of normal animals: 82% of infected CF mice, but only 23% of normal mice, died within 10 d of infection (P = 0.023). The concentration of inflammatory mediators, including TNF-alpha, murine macrophage inflammatory protein-2, and KC/N51, in bronchoalveolar lavage fluid in CF mice 3 d after infection and before any mortality, was markedly elevated compared with normal mice. This inflammatory response also correlated with weight loss observed in both CF and normal littermates after inoculation. Thus, this model may permit examination of the relationship of bacterial infections, inflammation, and the cellular and genetic defects in CF.

Probability of IV antibiotic retreatment within thirty days is associated with duration and location of IV antibiotic treatment for pulmonary exacerbation in cystic fibrosis.

BACKGROUND: There are few objective data to guide management of cystic fibrosis (CF) pulmonary exacerbations. We studied intravenous (IV) antibiotic treatment failure as defined by a need to retreat patients with IV antibiotics within 30days of completion of a prior IV antibiotic treatment for pulmonary exacerbation. METHODS: The first IV-treated exacerbation on or after Jan. 1, 2010 among US CF Foundation Patient Registry patients was studied, combining treatments separated by <7days into single treatments. IV treatment duration categories were: 1-4, 5-8, 9-12, 13-16, 17-22, and ≥23days (inclusive). Logistic regressions for IV retreatment in ≤30days were adjusted with 12 categorical covariates, including age, sex, lung function, prior-year exacerbations, CF complications, CF Care Program, and ever/never treated in hospital. RESULTS: 777 of 13,579 patients (5.7%) were retreated within 30days, with incidence varying by treatment duration: 1-4days, 8.7%; 5-8days; 6.6%; 9-12days, 3.2%; 13-16days, 4.5%; 17-22days, 6.2%; ≥23days, 10.3% and hospitalization: ever, 5.0%; never 8.5%. Adjusted odds ratios (OR) for retreatment (compared to 13-16days treatment) were: 1-4days, 1.94 [95%CI 1.49, 2.54] P<.001; 5-8days, 1.55 [1.18, 2.04] P=.002; 9-12days, 0.78 [0.58, 1.04] P=.09; 17-22days, 1.12 [0.88, 1.42] P=.37; ≥23days, 1.46 [1.12, 1.91] P=.005. Adjusted retreatment OR for never/ever hospitalized was 1.57 [1.29, 1.90] P<.001. Prior-year exacerbation number, oxygen therapy, non-invasive ventilation, and female sex were significantly associated with retreatment. Modeling hazard rate time-dependence showed that treatment duration and location-associated hazard rates attenuated within a few months after treatment. CONCLUSION: After adjustment for covariates known to be associated with increased risk of IV treatment for exacerbation, IV antibiotic treatments of <9 and ≥23days and those without hospitalization were significant risk factors for IV retreatment within 30days of completion of an exacerbation treatment.

Pitfall in the use of genotype analysis as the sole diagnostic criterion for cystic fibrosis.

In this report, we present an asymptomatic infant, seen for a second opinion, who was given the diagnosis of cystic fibrosis (CF) as a neonate based on the presence of two mutant alleles, DeltaF508 and R117H. The diagnosis of CF adversely affected the family's emotional, employment, and financial statuses. Our evaluation included sweat chloride, nasal transepithelial potential difference, and bronchoscopy with bronchoalveolar lavage measurements, all which were consistent with findings expected from an individual without CF. Genotype analysis for the sequence polymorphism in intron 8 of the cystic fibrosis transmembrane conductance regulator (CFTR) gene revealed the 7 thymidines and 9 thymidines alleles. We conclude that this patient probably expresses enough epithelial cell surface CFTR function such that she has a normal phenotype. Based on our evaluation, she does not meet the current diagnostic criteria for CF. Although genotype analysis can be an useful adjunct, it should not be the sole diagnostic criterion for CF.

Ultrase MT12 and Ultrase MT20 in the treatment of exocrine pancreatic insufficiency in cystic fibrosis: safety and efficacy.

BACKGROUND: Cystic fibrosis causes exocrine pancreatic insufficiency, leading to malabsorption. Supplemental pancreatic enzyme therapy alleviates the concomitant malnutrition experienced by cystic fibrosis patients. It is recognized that patients experience variations in clinical response to different brands of enzymes. This has prompted the US Food and Drug Administration to require that enzyme supplements be subjected to New Drug Applications. AIM: To investigate the safety and efficacy of supplemental pancreatic enzyme therapy in cystic fibrosis subjects. METHODS: We compared two doses of one formulation of enteric-coated pancreatic enzymes: Ultrase MT12 (12,000 lipase units per capsule) and Ultrase MT20 (20,000 lipase units per capsule), to placebo in two separate safety and efficacy studies. RESULTS: Mean total fat, protein and carbohydrate intake did not differ significantly between the groups. A significant difference in both fat and protein absorption occurred with the enzyme therapy groups. The Ultrase MT12 and Ultrase MT20 groups experienced a mean fat and protein absorption 79.4% and 83.8%, and 87.3% and 88.6%, respectively. No adverse events related to study drug were reported. CONCLUSIONS: This study further supports the use of enzymes to treat pancreatic insufficiency in cystic fibrosis. Excellent fat and protein absorption was achieved with minimal adverse events and safe doses.

The use of anti-inflammatory medications in cystic fibrosis: trends and physician attitudes.

STUDY OBJECTIVES: In recent years, there has been considerable interest in the use of antiinflammatory medications to decrease airway inflammation and preserve pulmonary function in patients with cystic fibrosis (CF) lung disease. Long-term use of oral corticosteroids (OCS) and ibuprofen (IBU) has been proven efficacious in slowing the progression of CF. Inhaled corticosteroids (ICS) have not been adequately studied. Little is known regarding use trends and physician attitudes toward these drugs. DESIGN: Cross-sectional survey mailed to 111 directors of Cystic Fibrosis Centers in the United States accredited by the Cystic Fibrosis Foundation. The two-page written questionnaire included items regarding physicians' attitudes toward anti-inflammatories, center demographics, patients receiving therapy, and number of physicians prescribing therapy. RESULTS: Sixty-seven surveys were returned (60%). The responding centers represented 239 physicians and served 9,363 patients, 2,234 (24%) of whom were receiving routine antiinflammatory drugs. Complete data sets were available for 8,803 patients with 2,169 (25%) receiving anti-inflammatory therapy. Ninety-eight (41%) physicians prescribed long-term use of oral steroids for 413 (5%) patients, 103 (42%) prescribed inhaled steroids for 1,032 (12%) patients, and 108 (45%) prescribed high-dose IBU for 723 (8%) patients to control CF. The practitioners reported familiarity and efficacy as the primary reasons for prescribing OCS; concerns over side effects were the major reason for not prescribing. Regarding ICS, the primary reasons for prescribing were familiarity and safety, with lack of efficacy being cited as the major reason for not prescribing. For IBU, efficacy was ranked highest among reasons for prescribing, with concern over safety being the highest ranked reason for not prescribing. CONCLUSIONS: Anti-inflammatory medications appear to be an underutilized therapeutic modality in CF care. This is true for numbers of patients receiving these drugs as well as numbers of care providers prescribing them. Additional studies will be required to address physicians' concerns regarding the long-term efficacy and safety of anti-inflammatory drugs in treating CF.

The pathologic characteristics of interstitial pneumonia cystic fibrosis. A retrospective autopsy study.

Interstitial pneumonia is a poorly understood variant of lung injury in patients with cystic fibrosis (CF). The authors identified prominent interstitial pneumonia (defined as an inflammatory reaction predominantly involving alveolar septa) in 9 of 43 autopsied patients with CF. Lungs from these nine were studied by light microscopy to determine the histopathologic features, clinicopathologic correlates, and potential causes of CF-associated interstitial pneumonia. Two histologic variants were identified, alveoloseptal (in which the inflammatory reaction was confined to the alveolar wall) and organizing (in which intraalveolar granulation tissue was present in addition to septal inflammation), which respectively affected four and five patients. Cholesterol deposits and capillary proliferation were prominent associated features in some patients. Interstitial pneumonia was not diagnosed antemortem and was identified on chest roentgenogram in only two patients. There were no distinctive clinical features associated with different histologic subtypes, nor did histologic or clinical data identify a specific cause(s) of interstitial pneumonia. The authors conclude that CF-associated interstitial pneumonia, although usually an incidental finding at autopsy, may potentially contribute to respiratory impairment and death. Although there are multiple possible causes of interstitial lung injury associated with CF, the authors were unable to identify, with certainty, the pathogenesis of interstitial pneumonia in any patient in this study.

Therapies aimed at airway inflammation in cystic fibrosis.

Therapies aimed at decreasing the inflammatory response present a new strategy for treating cystic fibrosis (CF) lung disease. Alternate day prednisone may be beneficial, however, unacceptable adverse effects limit long-term use. Inhaled corticosteroids are under investigation as a safer alternative. High-dose ibuprofen twice daily has been shown to decrease the progression of CF lung disease and is without significant toxicity. Other NSAIDs and pentoxifylline and fish oil are under consideration. Antiproteases and antioxidants are also being studied. The rationale for all of these agents lies in their potential to decrease neutrophil influx into the lung, and counteract injurious products of neutrophils. Adding anti-inflammatory therapy to an already comprehensive treatment program will hopefully decrease morbidity and improve the quality of life for patients with CF.

Current understanding of the inflammatory process in cystic fibrosis: onset and etiology.

Although airway obstruction and chronic endobronchial infection have long been recognized as major factors in the pathogenesis of lung disease in cystic fibrosis (CF), only recently has it been recognized that the inflammatory process itself may be responsible in a major way for destroying the lungs. The most characteristic feature of inflammation in the CF lung is the persistent infiltration of massive numbers of neutrophils into the airways. Although neutrophils help to control infection, when present in great excess, they cause more harm than good. Major advances in our understanding of the inflammatory process in the CF lung have come from the use of bronchoscopy and bronchoalveolar lavage (BAL) to analyze the inflammatory process in patients who are relatively symptom free and/or do not regularly produce sputum. Recent BAL studies suggest that neutrophil-rich inflammation begins very early, even in infants without clinically apparent lung disease. A number of chemoattractants from epithelial cells, macrophages, neutrophils themselves, and bacterial products contribute to the neutrophil influx. Surprisingly, some infants have inflammation even in the apparent absence of infection, leading to the speculation that inflammation may precede infection. Links between the basic defect in CF and inflammation have been postulated, with dysregulation of cytokine production and abnormal epithelial host defenses being implicated as causal factors of sustained inflammation. Regardless of the details of how this process is initiated and/or perpetuated, it has become clear that inflammation begins at a very early stage and progresses throughout life, gradually worsening and destroying the lungs. For these reasons, anti-inflammatory therapy should be initiated in early life. Additional studies are necessary to define the optimal antiinflammatory drugs and regimens, and to confirm their long-term safety and efficacy.

Patterns of medical practice in cystic fibrosis: part I. Evaluation and monitoring of health status of patients. Investigators and Coordinators of the Epidemiologic Study of Cystic Fibrosis.

This report characterizes patterns of evaluation and monitoring of the health status of patients with cystic fibrosis (CF) as observed in the Epidemiologic Study of Cystic Fibrosis (ESCF), and compares these practices to published guidelines. All patients (18,411) who enrolled in ESCF at 194 study sites in the United States and Canada from December 1, 1993 to December 31, 1995 were considered for study. Patients enrolled before January 1, 1995 with >/=1 healthcare encounters during 1995 (12,631) were included in the analysis. Patients enrolled after January 1, 1995 (5,266), or who died (354), withdrew from the study (128), or were lost to follow-up (21) were excluded. Frequency of encounters (outpatient and hospital), spirometry, respiratory tract cultures, and chest radiographs were recorded during a 1-year period (1995) and analyzed by gender, age, severity of lung disease, and presence of any Pseudomonas species in the respiratory tract. The 12,631 patients had 53,024 outpatient visits. In 57.5% of patients, the recommended criteria of >/=4 total visits per year were met. Only 27.4% of all patients had >/=4 routine visits; 3.1% had only sick visits, and 59.0% had no sick visits. One third (34.6%) were hospitalized at least once, for a total of 8,561 hospitalizations. Older patients with lower pulmonary function and Pseudomonas in their respiratory tract had fewer routine visits and more sick visits, and were hospitalized more than were younger patients. In three fourths (75.8%) of patients the recommended criterion of two spirometry assessments per year was met, whereas in 79.3% the criterion of one culture was met, and in 68.3% the criterion of one radiograph/year was met. We conclude that in the majority of CF patients, the recommended criteria for routine evaluation and monitoring were met. However, in a rather substantial number they were not. An increase in the utilization of healthcare resources was observed in patients with more severe disease. This information will help to establish benchmarks for future quality assessment programs.

Patterns of medical practice in cystic fibrosis: part II. Use of therapies. Investigators and Coordinators of the Epidemiologic Study of Cystic Fibrosis.

This report describes the prescribing pattern of therapeutic interventions in the management of patients with cystic fibrosis (CF), as observed in the Epidemiologic Study of Cystic Fibrosis (ESCF). Use of 20 therapies by 12,622 patients was recorded from each health care encounter (53,024 outpatient visits and 8,561 hospitalizations) during a 1-year period (1995), and analyzed by gender, age, severity of lung disease, and presence of any Pseudomonas species in the respiratory tract. The percentage of patients using the following pulmonary therapies was observed (in descending order): airway clearance techniques (88.2%); inhaled bronchodilators (82.2%); oral antibiotics (excluding quinolones) (68. 2%); dornase alfa (52.9%); intravenous antibiotics (34.4%); oral quinolones (34.4%); inhaled antibiotics (34.3%); mast cell stabilizers (29.5%); inhaled corticosteroids (25.9%); oral corticosteroids (17.1%); oral bronchodilators (16.2%); oxygen (8. 1%); inhaled mucolytic agent acetyl cysteine (6.5%); and diuretics (1.4%). The percentage of patients using nutritional therapies was: pancreatic enzymes (96%); oral nutritional supplements (31.1%); enteral nutrition (7.3%); and parenteral nutrition (0.7%). The percentage of patients using other therapies was: nonsteroidal anti-inflammatory drugs (7.9%); and insulin or oral hypoglycemic agents (6.1%). The general trend was for therapies to be used more by older patients, those with lower pulmonary function, and by those with Pseudomonas in their respiratory tract. Exceptions to this trend occurred for airway clearance, oral antibiotics, mast cell stabilizers, and pancreatic enzymes. Four therapies (oral nutritional supplements, parenteral nutrition, diuretics, and pancreatic enzymes) were used more by males than females. However, there was no gender difference for this group of therapies on pulmonary or nutritional status.

Effect of smaller droplet size of dornase alfa on lung function in mild cystic fibrosis. Dornase Alfa Nebulizer Group.

Aerosolized recombinant human DNase (dornase alfa) reduces mucus viscoelasticity in vitro and improves pulmonary function in patients with cystic fibrosis (CF). We postulated that if dornase alfa could be delivered more peripherally to small airways in the lung in the form of smaller aerosol droplets in patients with early airway obstruction, the increase in pulmonary function from baseline might be improved. CF patients (n = 749) with mild lung disease (baseline forced vital capacity > or = 70% predicted) were randomly assigned to receive dornase alfa 2.5 mg daily for 2 weeks by one of two nebulizer systems: 1) the Medic-Aid Durable SideStream nebulizer powered by the MobilAire Compressor (SS/MA) producing a droplet size with a mass median aerodynamic diameter (MMAD) of 2.1 microm; or 2) the Hudson T Up-draft nebulizer with a DeVilbiss Pulmo-Aide compressor (HT/PA) with an MMAD of 4.9 microm. Spirometry was performed at baseline and following 14 days of treatment. Dornase alfa delivered by both nebulizer systems produced small but statistically significant improvements in pulmonary function compared with baseline. There was a trend (P = 0.06) toward greater improvement in forced expiratory flow in 1 s in the SS/MA group (4.3%) compared with the HT/PA group (2.5%). These results indicate that the short-term spirometric response to dornase alfa is influenced in part by the physical characteristics of the aerosol in patients with mild lung disease. We speculate that this may be true for other therapeutic aerosols, and it appears that localization of disease in the lung plays a role in the response to inhaled agents.

Safety of aerosolized INS 365 in patients with mild to moderate cystic fibrosis: results of a phase I multi-center study.

Cystic fibrosis (CF) is characterized by defective cystic fibrosis transmembrane regulator (CFTR) expression and function, associated with abnormal ion transport and mucociliary clearance, and clinical lung disease. Triphosphate nucleotides such as uridine-5'-triphosphate (UTP) and INS 365, may be useful for CF through actions, mediated via P2Y(2) extracellular receptors, on chloride and liquid secretion, and ciliary beat frequency. INS 365 may offer chemical stability advantages over UTP. In a randomized, double-blind, multicenter phase I study, we studied the safety and maximally tolerated dose of escalating, single doses of aerosolized INS 365, in adult and pediatric patients with mild to moderate CF lung disease (FEV(1) > or = 45% predicted). In four successive dose cohorts of adult patients (n = 12 per cohort, age > or = 18 years) and four successive pediatric dose cohorts (n = 12 per cohort, age 5-12 years), patients were randomized 3:1 active/placebo (0.9% saline) to evaluate doses of 20, 40, 80, and 100 mg INS 365 delivered by nebulizer (Pari Star ). Sputum was collected pre- and post-dosing to obtain preliminary results on clinical efficacy. After each dose cohort, a Data Safety Monitoring Committee (DSMC) reviewed the data. Forty-eight adult and 36 pediatric patients completed the protocol (up to 100 mg for adults, 80 mg for pediatric patients). The predominant adverse events were cough, wheezing, chest tightness, and a decrease in FEV(1) (occurring in 8/48 adults, and 5/36 pediatric patients), which occurred predominantly in the 80-mg and 100-mg dose cohorts. Though a few adult patients had a tendency to increase sputum production, there was little consistent effect noted on sputum production in this acute, single-dose study. The data suggest that aerosolized INS 365 is safe when delivered at single doses of up to 40 mg in adults and children with CF, but that higher doses are unlikely to be tolerated.