Jochen G. Mainz

Efficacy and Safety of Ivacaftor in Patients Aged 6 to 11 Years with Cystic Fibrosis with a G551D Mutation

RATIONALE Ivacaftor (VX-770), a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator, has been shown to improve lung function, pulmonary exacerbation rate, respiratory symptoms, and weight gain compared with placebo in patients with cystic fibrosis aged 12 years or older with a G551D-CFTR mutation. OBJECTIVES This randomized, double-blind, placebo-controlled trial evaluated ivacaftor in patients with cystic fibrosis aged 6-11 years with a G551D-CFTR mutation on at least one allele. METHODS Patients were randomly assigned to receive ivacaftor administered orally at 150 mg (n = 26) or placebo (n = 26) every 12 hours for 48 weeks in addition to existing prescribed cystic fibrosis therapies. MEASUREMENTS AND MAIN RESULTS Despite near-normal mean baseline values in FEV1, patients receiving ivacaftor had a significant increase in percent predicted FEV1 from baseline through Week 24 versus placebo group (treatment effect, 12.5 percentage points; P < 0.001). Effects on pulmonary function were evident by 2 weeks, and a significant treatment effect was maintained through Week 48. Patients treated with ivacaftor gained, on average, 2.8 kg more than those receiving placebo at Week 48 (P < 0.001). The change from baseline through Week 48 in the concentration of sweat chloride, a measure of CFTR activity, with ivacaftor was -53.5 mmol/L (P < 0.001) versus placebo. The incidence of adverse events was similar in the two groups. CONCLUSIONS In patients who are younger and healthier than those in previously studied populations, ivacaftor demonstrated a significant improvement in pulmonary function, weight, and CFTR activity compared with placebo. Clinical trial registered with www.clinicaltrials.gov (NCT00909727).

Concordant genotype of upper and lower airways P aeruginosa and S aureus isolates in cystic fibrosis

Rationale: Lower airway (LAW) infection with Pseudomonas aeruginosa and Staphylococcus aureus is the leading cause of morbidity in cystic fibrosis (CF). The upper airways (UAW) were shown to be a gateway for acquisition of opportunistic bacteria and to act as a reservoir for them. Therefore, tools for UAW assessment within CF routine care require evaluation. Objectives: The aims of the study were non-invasive assessment of UAW and LAW microbial colonisation, and genotyping of P aeruginosa and S aureus strains from both segments. Methods: 182 patients with CF were evaluated (age 0.4–68 years, median 17 years). LAW specimens were preferably sampled as expectorated sputum and UAW specimens by nasal lavage. P aeruginosa and S aureus isolates were typed by informative single nucleotide polymorphisms (SNPs) or by spa typing, respectively. Results: Of the typable S aureus and P aeruginosa isolates from concomitant UAW- and LAW-positive specimens, 31 of 36 patients were carrying identical S aureus spa types and 23 of 24 patients identical P aeruginosa SNP genotypes in both compartments. Detection of S aureus or P aeruginosa in LAW specimens was associated with a 15- or 88-fold higher likelihood also to identify S aureus or P aeruginosa in a UAW specimen from the same patient. Conclusions: The presence of identical genotypes in UAW and LAW suggests that the UAW play a role as a reservoir of S aureus and P aeruginosa in CF. Nasal lavage appears to be suitable for non-invasive UAW sampling, but further longitudinal analyses and comparison with invasive methods are required. While UAW bacterial colonisation is typically not assessed in regular CF care, the data challenge the need to discuss diagnostic and therapeutic standards for this airway compartment. Trial registration number: NCT00266474.

Management of chronic rhinosinusitis in CF

Routine CF management often does not include upper airway (UAW) assessment although CFTR defects equally affect the sinonasal mucosa. Up to 50% of CF patients have chronic rhinosinusitis (CRS) and/or nasal polyps, and almost 100% reveal UAW abnormalities on CT scan. CRS impairs quality of life. UAW dysfunction in filtering, humidifying, and warming inspired air affects lower airways and the UAW is a potential site of first colonization and a reservoir for opportunistic bacteria. Therefore, UAW pathology substantially affects overall health in CF. Standard treatments are scarce and mostly lack evidence. Nasal douche can remove mucus and crusts. Recently, delivery of dornase alfa using a vibrating aerosol has shown potential as treatment for CF-related CRS. Surgery is indicated when conservative approaches fail but postoperative relapse is frequent. In summary, upper airway involvement in CF is undertreated and requires prospective investigation and an interdisciplinary consensus on diagnosis and therapy.

Sinonasal persistence of Pseudomonas aeruginosa after lung transplantation

UNLABELLED We report on two CF patients who received double lung transplantation (LTX) due to Pseudomonas aeruginosa related pulmonary destruction. Prior to LTX we detected P. aeruginosa in nasal lavages (NL) and sputum cultures from both patients. Donor lungs of patient 1 became colonized within four weeks with P. aeruginosa identical in genotype with isolates from his pre-transplant sputum cultures and pre- and post-transplant NL. In contrast, patient 2 remained P. aeruginosa free in lower airway samples (bronchial lavage/sputum) for now up to 30 months, despite persistent detection of P. aeruginosa that was identical in genotype with pre-transplant NL and sputum isolates in NL and even in throat swabs. For prevention of pulmonary re-colonization patient 2 has continuously inhaled Colomycin 1 MIU once daily during the preceding more than 36 months with the novel Pari Sinus™ nebulizer, which in scintigraphic studies was shown to deliver vibrating aerosols into paranasal sinuses, additional to bronchial antibiotic inhalation. DISCUSSION Pulmonary colonization of transplanted donor lungs with identical clones previously colonizing the explanted lungs has been described previously and the upper airways were postulated as reservoir for descending colonization. However, this remained speculative, as upper airway sampling which does not belong to current standards, was not performed in these studies. Our report demonstrates persistence of identical P. aeruginosa genotypes in CF upper airways prior to and after LTX underlining risks of descending colonization of transplanted lungs with P. aeruginosa, which increases risks of graft dysfunction. Therefore, we recommend regular assessment of sinonasal colonization prior to and after LTX. Sinonasal inhalation with antimicrobials should be investigated in prospective trials.

Therapy of CF-Patients with Amitriptyline and Placebo - a Randomised, Double-Blind, Placebo-Controlled Phase IIb Multicenter, Cohort-Study

Background/Aims: Several recent studies revealed an accumulation of ceramide in bronchial, tracheal and intestinal epithelial cells of mice and patients with cystic fibrosis (CF). Normalization of ceramide concentrations in lungs of CF mice employing the functional acid sphingomyelinase inhibitor amitriptyline also normalized mucociliary clearance, chronic inflammation and infection susceptibility to pulmonary P. aeruginosa in these mice. Methods: To test for a beneficial effect of amitriptyline in vivo, we performed a phase IIb randomised, double-blind, placebo-controlled study. Twenty-one CF patients were treated with 25 mg/d amitriptyline twice daily for 28 days. The placebo consisted of 19 patients and was also treated twice per day. The primary endpoint was the change in lung function in the intention-to-treat (ITT) population. Secondary endpoints were ceramide levels in epithelial cells and safety. Results: After treatment, forced expiratory volume in 1 sec predicted (FEV1) increased 6.3±11.5% (p=0.08) in the ITT population (36 of 40 CF patients) and 8.5±10% (p=0.013) in the per protocol (PP) population (29 of 40 patients). Ceramide levels decreased in nasal epithelial cells after amitriptyline treatment. Amitriptyline had no severe and only mild and mostly transient adverse effects, i.e. xerostomia and tiredness. Conclusion: Amitriptyline is safe in CF-patients, increases FEV1 and reduces ceramide in lung cells of CF patients.

Pathogenesis and Management of Nasal Polyposis in Cystic Fibrosis

Beginning in preschool age, during their lives, up to 50% of cystic fibrosis (CF) patients experience obstructing nasal polyposis (NP), which is rare in non-CF children. Pathogenetic factors of NP in general and especially in CF are still obscure. However, defective epithelial ion transport from mucosal glands plays a central role in CF, and viscous secretions impair mucociliary clearance, promoting chronic pathogen colonization and neutrophil-dominated chronic inflammation. Presently, CF-NP is not curable but can be clinically stabilized, though the large variety of proposed treatment modalities indicates a lack of standardization and of evidence of treatment efficacy. When conservative measures are exhausted, surgical intervention combining individually adapted endoscopic sinus surgery and supportive conservative treatment is performed. Topical steroids, approved as the gold standard for non-CF NP, may be beneficial, but they are discussed to be less effective in neutrophilic inflammation, and CF-specific antimicrobial and mucolytic therapy, as is true of all treatment modalities, urgently requires evaluation by controlled clinical trials within interdisciplinary networks.

Sinonasal inhalation of tobramycin vibrating aerosol in cystic fibrosis patients with upper airway Pseudomonas aeruginosa colonization: results of a randomized, double-blind, placebo-controlled pilot study

Rationale In cystic fibrosis (CF), the paranasal sinuses are sites of first and persistent colonization by pathogens such as Pseudomonas aeruginosa. Pathogens subsequently descend to the lower airways, with P. aeruginosa remaining the primary cause of premature death in patients with the inherited disease. Unlike conventional aerosols, vibrating aerosols applied with the PARI Sinus™ nebulizer deposit drugs into the paranasal sinuses. This trial assessed the effects of vibrating sinonasal inhalation of the antibiotic tobramycin in CF patients positive for P. aeruginosa in nasal lavage. Objectives To evaluate the effects of sinonasal inhalation of tobramycin on P. aeruginosa quantification in nasal lavage; and on patient quality of life, measured with the Sino-Nasal Outcome Test (SNOT-20), and otologic and renal safety and tolerability. Methods Patients were randomized to inhalation of tobramycin (80 mg/2 mL) or placebo (2 mL isotonic saline) once daily (4 minutes/nostril) with the PARI Sinus™ nebulizer over 28 days, with all patients eligible for a subsequent course of open-label inhalation of tobramycin for 28 days. Nasal lavage was obtained before starting and 2 days after the end of each treatment period by rinsing each nostril with 10 mL of isotonic saline. Results Nine patients participated, six initially receiving tobramycin and three placebo. Sinonasal inhalation was well tolerated, with serum tobramycin <0.5 mg/L and stable creatinine. P. aeruginosa quantity decreased in four of six (67%) patients given tobramycin, compared with zero of three given placebo (non-significant). SNOT-20 scores were significantly lower in the tobramycin than in the placebo group (P=0.033). Conclusion Sinonasal inhalation of vibrating antibiotic aerosols appears promising for reducing pathogen colonization of paranasal sinuses and for control of symptoms in patients with CF.

Influences of nasal lavage collection-, processing- and storage methods on inflammatory markers--evaluation of a method for non-invasive sampling of epithelial lining fluid in cystic fibrosis and other respiratory diseases.

BACKGROUND Non-invasive sampling of airway epithelial-lining-fluid by nasal lavage (NL) is an emerging method to monitor allergy, infection and inflammation in patients with respiratory diseases. However, the influences of collection-, processing- and storage-methods have not been sufficiently evaluated and standardized. METHODS Influences of repeated NL, centrifugation setups, repeated freezing and thawing, and protease inhibitors on mediator concentration were evaluated in healthy controls and CF patients, which serve as a model for chronic bacterial infection and inflammation. Polymorphonuclear leukocyte elastase (NE)/myeloperoxidase (MPO)/interleukin (IL)-1/IL-6/IL-8 and tumour necrosis factor alpha (TNF) concentrations were measured using ELISA and Multiplex Bead-Arrays. RESULTS NL-repetition within 0.5-4h markedly decreased NE, IL-8 and MPO-concentrations for up to 70%. NL centrifugation up to 250×g for cellular differentiation did not significantly influence mediator concentration in native and processed NL fluid. NL freezing and thawing markedly decreased IL-8 and MPO concentrations by up to 50% while NE remained stable. In contrast to preceding reports, storing at -70°C for ≥5 years led to significantly reduced mediator concentrations in NL compared to contemporary analyses, being most pronounced for IL-1β, IL-6 and TNFa. Storing of samples in the presence of protease inhibitors led to an increase in marker concentration for IL-8 (+27%) and MPO (+15%) even after one year of storage. CONCLUSIONS NL is an easy and robust technique for inflammation monitoring of the upper airways. For the first time we have shown that diagnostic NL should be performed only once daily to get comparable results. Whereas NL-fluid can be stored unprocessed at -70°C for cytokine analysis over 1-2 years with protease inhibitors supporting stability, ≥5 years storage as well as repeated freezing and thawing should be avoided.

Aspects of pulmonary drug delivery strategies for infections in cystic fibrosis – where do we stand?

Introduction: Cystic fibrosis (CF) is the most common life-shortening hereditary disease among Caucasians and is associated with severe pulmonary damage because of decreased mucociliary clearance and subsequent chronic bacterial infections. Approximately 90% of CF patients die from lung destruction, promoted by pathogens such as Pseudomonas aeruginosa. Consequently, antibiotic treatment is a cornerstone of CF therapy, preventing chronic infection and reducing bacterial load, exacerbation rates and loss of pulmonary function. Many drugs are administered by inhalation to achieve high pulmonary concentration and to lower systemic side effects. However, pulmonary deposition of inhaled drugs is substantially limited by bronchial obstruction with viscous mucus and restrained by intrapulmonary bacterial biofilms. Areas covered: This review describes challenges in the therapy of CF-associated infections by inhaled antibiotics and summarizes the current state of microtechnology and nanotechnology-based pulmonary antibiotic delivery strategies. Recent and ongoing clinical trials as well as experimental approaches for microparticle/nanoparticle-based antibiotics are presented and their advantages and disadvantages are discussed. Expert opinion: Rapidly increasing antimicrobial resistance accompanied by the lack of novel antibiotics force targeted and more efficient use of the available drugs. Encapsulation of antimicrobials in nanoparticles or microparticles of organic polymers may have great potential for use in CF therapy.

Non-invasive assessment of upper and lower airway infection and inflammation in CF patients

The upper (UAW) and lower (LAW) airways of patients with cystic fibrosis (CF) have the same ion‐channel defects, but little is known about similarities and differences in host immunological responses at the two levels.