Inhaled antibiotics for the treatment of chronic Pseudomonas aeruginosa infection in cystic fibrosis patients: challenges to treatment adherence and strategies to improve outcomes

ALPINE2: Efficacy and safety of 14-day vs 28-day inhaled aztreonam for Pa eradication in children with cystic fibrosis

BACKGROUND

Antibiotic eradication therapies recommended for newly isolated Pseudomonas aeruginosa (Pa) in people with cystic fibrosis (pwCF) can be burdensome. ALPINE2 compared the efficacy and safety of a shortened 14-day course of aztreonam for inhalation solution (AZLI) with 28-day AZLI in paediatric pwCF.

METHODS

ALPINE2 (a double-blind, phase 3b study) included children aged 3 months to <18 years with CF and new-onset Pa infection. Participants were randomized to receive 75 mg AZLI three times daily for either 28 or 14 days followed by 14 days' matched placebo. The primary endpoint was rate of primary Pa eradication (no Pa detected during the 4 weeks post AZLI treatment). Non-inferiority was achieved if the lower 95% CI bound of the treatment difference between the two arms was above -20%. Secondary endpoints included assessments of Pa recurrence during 108 weeks of follow-up after primary eradication. Safety endpoints included treatment-emergent adverse events (TEAEs).

RESULTS

In total, 149 participants were randomized (14-day AZLI, n = 74; 28-day AZLI, n = 75) and 142 (95.3%) completed treatment. Median age: 6.0 years (range: 0.3-17.0). Baseline characteristics were similar between treatment arms. Primary Pa eradication rates: 14-day AZLI, 55.9%; 28-day AZLI, 63.4%; treatment difference (CI), -8.0% (-24.6, 8.6%). Pa recurrence rates at follow-up end: 14-day AZLI, 54.1% (n = 20/37); 28-day AZLI, 41.9% (n = 18/43). TEAEs were similar between treatment arms. No new safety signals were observed.

CONCLUSIONS

Non-inferiority of 14-day AZLI versus 28-day AZLI was not demonstrated. Both courses were well tolerated, further supporting AZLI short-term safety in paediatric and adolescent pwCF.

CLINICALTRIALS

GOV: NCT03219164.

Digital technology for monitoring adherence to inhaled therapies in people with cystic fibrosis

BACKGROUND

Improved understanding and treatment of cystic fibrosis (CF) has led to longer life expectancy, which is accompanied by an increasingly complex regimen of treatments. Suboptimal adherence to the treatment plan, in the context of respiratory disease, has been found to be associated with poorer health outcomes. With digital technology being more accessible, it can be used to monitor adherence to inhaled therapies via chipped nebulisers, mobile phone apps and web-based platforms. This technology can allow monitoring of adherence as well as clinical outcomes, and allow feedback to both the person with CF and their healthcare team.

OBJECTIVES

To assess the effects of using digital technology to monitor adherence to inhaled therapies and health status in adults and children with CF.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books.  Date of last search: 28 October 2021. We also searched Embase and three clinical trial registries and checked references of included studies. Date of last search: 9 November 2021.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) looking at the effects of a digital technology for monitoring adherence of children and adults with CF to inhaled therapies.

DATA COLLECTION AND ANALYSIS

Two review authors screened the search results for studies eligible for inclusion in the review and extracted their data. We used Risk of Bias 2 for assessing study quality. We assessed the overall certainty of the evidence using GRADE.

MAIN RESULTS

We included two studies in our review, with 628 participants aged five to 41 years. There was one study each for two different comparisons.  Nebuliser target inhalation mode versus standard inhalation mode The included parallel study was carried out over 10 weeks after a run-in period of four to six weeks. The study compared the effects of a digitally enhanced inhalation mode (target inhalation mode) for nebulised antibiotics compared to standard mode in children attending a regional CF clinic in the United Kingdom. The study's primary outcome was the time taken to complete the inhaled treatment, but investigators also reported on adherence to therapy. The results showed that there may be an improvement in adherence with the target inhalation mode when this intervention is used (mean difference (MD) 24.0%, 95% confidence interval (CI) 2.95 to 45.05; low-certainty evidence). The target inhalation mode may make little or no difference to forced expiratory volume in one second (FEV1) % predicted (MD 1.00 % predicted, 95% CI -9.37 to 11.37; low-certainty evidence). The study did not report on treatment burden, quality of life (QoL) or pulmonary exacerbations. eNebuliser with digital support versus eNebuliser without support One large multicentre RCT monitored adherence via data-tracking nebulisers. The intervention group also receiving access to an online web-based platform, CFHealthHub, which offered tailored, flexible support from the study interventionist as well as access to their adherence data, educational and problem-solving information throughout the 12-month trial period. We graded all evidence as moderate certainty. Compared to usual care, the digital intervention probably improves adherence to inhaled therapy (MD 18%, 95% CI 12.90 to 23.10); probably leads to slightly reduced treatment burden (MD 5.1, 95% CI 1.79 to 8.41); and may lead to slightly improved FEV1 % predicted (MD 3.70, 95% CI -0.23 to 7.63). There is probably little or no difference in the incidence of pulmonary exacerbations or QoL between the two groups.

AUTHORS' CONCLUSIONS

Digital monitoring plus tailored support via an online platform probably improves adherence to inhaled therapies and reduces treatment burden (but without a corresponding change in QoL) in the medium term (low- and moderate-certainty evidence). In a shorter time frame, technological enhancement of inhaling antibiotics may improve adherence to treatment (low-certainty evidence). There may be little or no effect on lung function with either intervention, and online monitoring probably makes no difference to pulmonary exacerbations.  Future research should assess the effect of digital technology on adherence in both children and adults. Consideration of adherence to the total treatment regimen is also important, as an improvement in adherence to inhaled therapies could come at the cost of adherence to other parts of the treatment regimen.

Assessment of adherence to at-home oral anti-infective therapy among paediatric patients discharged from a Quebec hospital

OBJECTIVES

Non-adherence to anti-infective therapy contributes to treatment failure and the emergence of bacterial resistance. This study aimed to assess at-home adherence, by paediatric patients, to oral anti-infective (OAI) therapy prescribed for treatment of acute infections and to explore the factors contributing to non-adherence.

METHODS

This prospective descriptive study involved French-speaking patients under 16 years of age who were discharged with one or more OAIs prescribed for home administration for a maximum of 30 days. Telephone surveys were used to assess overall adherence, which consisted of primary adherence (patient's ability to procure the medication) and secondary adherence (patient's ability to take the treatment as prescribed).

RESULTS

Overall, 51.7% (30/58) of patients were adherent to OAI therapy, with 100% primary adherence (n=69/69) and 51.7% secondary adherence (n=30/58). On average, patients took 98% of the total number of doses prescribed, and non-adherence was related mostly to not following medication administration schedules (63.3% of patients followed the exact schedule). Indeed, the adherence rate for patients taking one or two doses per day was twice the rate for patients taking more than two doses per day (81.8% vs 44.7%, p=0.043).

CONCLUSIONS

Half of the paediatric patients treated for acute infections were non-adherent to OAI therapy at home. Interventions are needed to improve this situation.

Indian Guidelines on Nebulization Therapy

Inhalational therapy, today, happens to be the mainstay of treatment in obstructive airway diseases (OADs), such as asthma, chronic obstructive pulmonary disease (COPD), and is also in the present, used in a variety of other pulmonary and even non-pulmonary disorders. Hand-held inhalation devices may often be difficult to use, particularly for children, elderly, debilitated or distressed patients. Nebulization therapy emerges as a good option in these cases besides being useful in the home care, emergency room and critical care settings. With so many advancements taking place in nebulizer technology; availability of a plethora of drug formulations for its use, and the widening scope of this therapy; medical practitioners, respiratory therapists, and other health care personnel face the challenge of choosing appropriate inhalation devices and drug formulations, besides their rational application and use in different clinical situations. Adequate maintenance of nebulizer equipment including their disinfection and storage are the other relevant issues requiring guidance. Injudicious and improper use of nebulizers and their poor maintenance can sometimes lead to serious health hazards, nosocomial infections, transmission of infection, and other adverse outcomes. Thus, it is imperative to have a proper national guideline on nebulization practices to bridge the knowledge gaps amongst various health care personnel involved in this practice. It will also serve as an educational and scientific resource for healthcare professionals, as well as promote future research by identifying neglected and ignored areas in this field. Such comprehensive guidelines on this subject have not been available in the country and the only available proper international guidelines were released in 1997 which have not been updated for a noticeably long period of over two decades, though many changes and advancements have taken place in this technology in the recent past. Much of nebulization practices in the present may not be evidence-based and even some of these, the way they are currently used, may be ineffective or even harmful. Recognizing the knowledge deficit and paucity of guidelines on the usage of nebulizers in various settings such as inpatient, out-patient, emergency room, critical care, and domiciliary use in India in a wide variety of indications to standardize nebulization practices and to address many other related issues; National College of Chest Physicians (India), commissioned a National task force consisting of eminent experts in the field of Pulmonary Medicine from different backgrounds and different parts of the country to review the available evidence from the medical literature on the scientific principles and clinical practices of nebulization therapy and to formulate evidence-based guidelines on it. The guideline is based on all possible literature that could be explored with the best available evidence and incorporating expert opinions. To support the guideline with high-quality evidence, a systematic search of the electronic databases was performed to identify the relevant studies, position papers, consensus reports, and recommendations published. Rating of the level of the quality of evidence and the strength of recommendation was done using the GRADE system. Six topics were identified, each given to one group of experts comprising of advisors, chairpersons, convenor and members, and such six groups (A-F) were formed and the consensus recommendations of each group was included as a section in the guidelines (Sections I to VI). The topics included were: A. Introduction, basic principles and technical aspects of nebulization, types of equipment, their choice, use, and maintenance B. Nebulization therapy in obstructive airway diseases C. Nebulization therapy in the intensive care unit D. Use of various drugs (other than bronchodilators and inhaled corticosteroids) by nebulized route and miscellaneous uses of nebulization therapy E. Domiciliary/Home/Maintenance nebulization therapy; public & health care workers education, and F. Nebulization therapy in COVID-19 pandemic and in patients of other contagious viral respiratory infections (included later considering the crisis created due to COVID-19 pandemic). Various issues in different sections have been discussed in the form of questions, followed by point-wise evidence statements based on the existing knowledge, and recommendations have been formulated.

Cystic Fibrosis: Recent Insights into Inhaled Antibiotic Treatment and Future Perspectives

Although new inhaled antibiotics have profoundly improved respiratory diseases in cystic fibrosis (CF) patients, lung infections are still the leading cause of death. Inhaled antibiotics, i.e., colistin, tobramycin, aztreonam lysine and levofloxacin, are used as maintenance treatment for CF patients after the development of chronic Pseudomonas aeruginosa (P. aeruginosa) infection. Their use offers advantages over systemic therapy since a relatively high concentration of the drug is delivered directly to the lung, thus, enhancing the pharmacokinetic/pharmacodynamic parameters and decreasing toxicity. Notably, alternating treatment with inhaled antibiotics represents an important strategy for improving patient outcomes. The prevalence of CF patients receiving continuous inhaled antibiotic regimens with different combinations of the anti-P. aeruginosa antibiotic class has been increasing over time. Moreover, these antimicrobial agents are also used for preventing acute pulmonary exacerbations in CF. In this review, the efficacy and safety of the currently available inhaled antibiotics for lung infection treatment in CF patients are discussed, with a particular focus on strategies for eradicating P. aeruginosa and other pathogens. Moreover, the effects of long-term inhaled antibiotic therapy for chronic P. aeruginosa infection and for the prevention of pulmonary exacerbations is reviewed. Finally, how the mucus environment and microbial community richness can influence the efficacy of aerosolized antimicrobial agents is discussed.

Assessment of anti-infective medication adherence in pediatric outpatients

The objective of this pilot study was to assess the overall adherence rate of the pediatric population to anti-infective drugs prescribed for acute infection at hospital discharge and to identify risk factors for non-adherence behavior. Pediatric patients discharged from a French university hospital with at least one oral drug prescription for acute infection were included for 3 months. Medication adherence and antibiotic knowledge were assessed through data collected by calling the parents. Overall adherence was assessed according to seven items: medication order filling, administered dose, time of intake, frequency of doses, medication omission, dose modification, and length of treatment. Seventy-five patients were included, and 63 interviews were exploited. The median age was 1.4 years, IQR = [0.7; 3.3]. Overall adherence to anti-infective agents concerned 34.9% of patients. The most frequently prescribed antibiotics were amoxicillin (29.3%), amoxicillin associated with clavulanic acid (25.3%), cotrimoxazole (18.7%), and cefixime (12.0%). A lack of parents' anti-infective knowledge was associated with non-adherence to anti-infective drugs.Conclusion: Two-thirds of outpatients were non-adherent to anti-infectives in acute infectious diseases. The misunderstanding of anti-infective treatment could be a risk factor for non-adherence. Implementation of preventive actions such as therapeutic education or pharmaceutical counseling at hospital discharge could improve adherence to anti-infective agents. What Is Known: • Non-adherence to anti-infective drugs involves the emergence and spread of antibiotic resistance. • Very few studies have assessed medication adherence in acute infectious diseases in pediatrics after hospital discharge. What Is New: • Only 35% of children were overall adherent to anti-infective drugs in acute infectious disease after hospital discharge. • Most patients (89%) had a good primary adherence but very few (40%) had good secondary adherence mainly due to dose omission and dose modification.

Pharmacokinetics and safety of tobramycin nebulization with the I-neb and PARI-LC Plus in children with cystic fibrosis: A randomized, crossover study

AIMS

We aimed to compare the pharmacokinetics (PK) and safety profile of tobramycin inhalation solution (TIS) using the I-neb device to the standard PARI-LC Plus nebulizer in children with cystic fibrosis.

METHODS

A randomized, open-label, crossover study was performed. In 2 separate study visits, blood samples from 22 children were collected following TIS nebulization with I-neb (75 mg) and PARI-LC Plus (300 mg). Study visits were separated by 1 month, in which 1 of the study nebulizers was used twice daily. Tobramycin PK for both nebulizers was established using measured tobramycin concentrations and Bayesian PK modelling software. Hearing and renal function tests were performed to test for aminoglycoside associated toxicity. In addition to standard estimated glomerular filtration rate values, biomarkers for tubular injury (KIM-1 and NAG) were measured. Patient and nebulizer satisfaction were assessed.

RESULTS

Inhalations were well tolerated and serum trough concentrations below the predefined toxic limit were reached with no significant differences in PK parameters between nebulizers. Results of audiometry and estimated glomerular filtration rate revealed no abnormalities. However, increased urinary NAG/creatinine ratios at visit 2 for both nebulizers suggest TIS-induced subclinical tubular kidney injury. Nebulization time was 50% shorter and patient satisfaction was significantly higher with the I-neb.

CONCLUSIONS

Nebulization of 75 mg TIS with the I-neb in children with cystic fibrosis resulted in comparable systemic exposure to 300 mg TIS with the PARI-LC Plus and was well tolerated and preferred over the PARI-LC Plus. Long-term safety of TIS nebulization should be monitored clinically, especially regarding the effects on tubular kidney injury.

Adherence to Aerosol Therapy in Young People With Cystic Fibrosis: Patient and Parent Perspectives Following Electronic Data Capture

The benefits of improved treatments for cystic fibrosis (CF) depend on optimal adherence, which remains problematic, particularly to aerosol therapy. In this study, we explored the process of adhering to aerosol therapy from the perspective of both adolescents with CF and their parents. Interviews were conducted individually with six adolescents and six parents, informed by accurate adherence data from an electronically chipped, aerosol device. Interview transcripts from audio-recordings were analyzed using grounded theory method (GTM). Major themes revealed differences in perspective between parent and adolescent, with this relationship mediating the cognitive and emotional processes that play a significant role in adherence behavior. These processes are further influenced by interactions with the aerosol therapy treatment regimen, device characteristics, and the context in which adherence is taking place. Parents and adolescents have different views of treatment and how to manage it. Both need to be addressed if optimal adherence is to be achieved.

The Structure of ampG Gene in Pseudomonas aeruginosa and Its Effect on Drug Resistance

In order to study the relationship between the structure and function of AmpG, structure, site-specific mutation, and gene complementary experiments have been performed against the clinical isolates of Pseudomonas aeruginosa. We found that there are 51 nucleotide variations at 34 loci over the ampG genes from 24 of 35 P. aeruginosa strains detected, of which 7 nucleotide variations resulted in amino acid change. The ampG variants with the changed nucleotides (amino acids) could complement the function of ampG deleted PA01 (PA01ΔG). The ampicillin minimum inhibitory concentration (MIC) of PA01ΔG complemented with 32 ampG variants was up to 512 μg/ml, similar to the original PA01 (P. aeruginosa PA01). Furthermore, site-directed mutation of two conservative amino acids (I53 and W90) showed that when I53 was mutated to 53S or 53T (I53S or I53T), the ampicillin MIC level dropped drastically, and the activity of AmpC β-lactamase decreased as well. By contrast, the ampicillin MIC and the activity of AmpC β-lactamase remained unchanged for W90R and W90S mutants. Our studies demonstrated that although nucleotide variations occurred in most of the ampG genes, the structure of AmpG protein in clinical isolates is stable, and conservative amino acid is necessary to maintain normal function of AmpG.

Adherence to tobramycin inhaled powder vs inhaled solution in patients with cystic fibrosis: analysis of US insurance claims data

PURPOSE

Tobramycin inhalation powder (TIP), the first dry-powder inhaled antibiotic for pulmonary Pseudomonas aeruginosa infection, is associated with reduced treatment burden, increased patient satisfaction, and higher self-reported adherence for cystic fibrosis (CF) patients. We compared adherence in CF patients newly treated with TIP with those newly treated with the traditional tobramycin inhalation solution (TIS), using US insurance claims data.

PATIENTS AND METHODS

From the Truven MarketScan^® database, we identified CF patients chronically infected with P. aeruginosa who had been prescribed TIP between May 1, 2013 to December 31, 2014, or TIS between September 1, 2010 to April 30, 2012 with at least 12 months of continuous medical and pharmacy benefits prior to and following prescription. TIP and TIS adherence levels were assessed.

RESULTS

A total of 145 eligible patients were identified for the TIP cohort and 306 for the TIS cohort. Significant differences in age distribution (25.0 vs 21.9 years for TIP vs TIS, respectively, P=0.017), type of health plan (P=0.014), employment status (72.4% vs 63.4% of TIP vs TIS patients in full-time employment, P=0.008), and some comorbidities were observed between the two cohorts. Although a univariate analysis found no significant differences between TIP and TIS (odds ratio [OR] 1.411, 95% confidence interval [CI] 0.949-2.098), TIP was moderately associated with higher adherence levels compared with TIS in a multivariable analysis, once various demographic and clinical characteristics were adjusted for. These included geographic location (OR: 1.566, CI: 1.016-2.413) and certain comorbidities.

CONCLUSION

This study of US patient data supports previous findings that TIP is associated with better adherence compared with TIS; however, further studies will be required to fully elucidate differences in adherence between TIP and TIS.