Clinical trial participants compared with nonparticipants in cystic fibrosis

Research Coordinators' Perspectives on Recruitment of Minoritized People with Cystic Fibrosis into Clinical Trials

Background

Clinical trials in cystic fibrosis (CF) disproportionately over-represent non-Hispanic, White individuals. Barriers and facilitators to enrolling racially and ethnically minoritized individuals with CF are not well understood. This study explored research coordinator (RC) perspectives on recruitment and enrollment of minoritized people with CF (PwCF) into clinical trials.

Methods

A cross-sectional survey was administered to RCs in the CF Therapeutics Development Network (CF TDN), eliciting perceived barriers and facilitators to inclusion of minoritized PwCF in clinical research. Respondents were categorized based on their self-reported experience discussing and successfully enrolling minoritized PwCF into clinical trials.

Results

Among 48 respondents, the majority (n = 31, 64%) had little to no experience discussing CF clinical trials with minoritized PwCF. Respondents who had a moderate or great deal of experience identified that having a trusted clinical team member first introduce the study to PwCF as the most common strategy for recruitment. Experienced respondents also identified the importance of having team members who speak the same language or are the same culture as the minoritized PwCF. Respondents who had little to no experience successfully enrolling minoritized PwCF into clinical trials cited low numbers of minoritized patients at their study center as an important consideration. All respondents emphasized language barriers in enrollment including need for adequate translation services and printed materials in the PwCF's primary language.

Conclusion

Our study identified modifiable barriers that may be addressed at the level of trial design and study center.

Evaluating precision medicine tools in cystic fibrosis for racial and ethnic fairness

Introduction

Patients with cystic fibrosis (CF) experience frequent episodes of acute decline in lung function called pulmonary exacerbations (PEx). An existing clinical and place-based precision medicine algorithm that accurately predicts PEx could include racial and ethnic biases in clinical and geospatial training data, leading to unintentional exacerbation of health inequities.

Methods

We estimated receiver operating characteristic curves based on predictions from a nonstationary Gaussian stochastic process model for PEx within 3, 6, and 12 months among 26,392 individuals aged 6 years and above (2003-2017) from the US CF Foundation Patient Registry. We screened predictors to identify reasons for discriminatory model performance.

Results

The precision medicine algorithm performed worse predicting a PEx among Black patients when compared with White patients or to patients of another race for all three prediction horizons. There was little to no difference in prediction accuracies among Hispanic and non-Hispanic patients for the same prediction horizons. Differences in F508del, smoking households, secondhand smoke exposure, primary and secondary road densities, distance and drive time to the CF center, and average number of clinical evaluations were key factors associated with race.

Conclusions

Racial differences in prediction accuracies from our PEx precision medicine algorithm exist. Misclassification of future PEx was attributable to several underlying factors that correspond to race: CF mutation, location where the patient lives, and clinical awareness. Associations of our proxies with race for CF-related health outcomes can lead to systemic racism in data collection and in prediction accuracies from precision medicine algorithms constructed from it.

How representative are clinical trial cohorts of the general CF population? Implications for trial planning

Understanding the number of patients eligible to participate in research is important to design protocols and define research priorities. We reviewed the records of all patients with CF, age 12+, who receive care at our centre. We assessed their eligibility for trial participation based on common trial inclusion/exclusion criteria. 643 patients were included in the analysis, 31 were modulator ineligible(MI). Only 198(31 %) of the total cohort and 7(23 %) of the MI cohort were eligible for participation based on the hypothetical criteria. The most common reason for ineligibility was ppFEV1 ≥90 % followed by clinical instability, complex comorbidity and anticipated inability to adhere to the protocol. We suggest this would be a useful exercise for centres planning to either participate in, or refer subjects into, upcoming trials to undertake for their own cohort. We also make suggestions for protocol designs that optimise the number of patients who are eligible to participate.

Aiming to Improve Equity in Pulmonary Health: Cystic Fibrosis

This review summarizes the evidence of health disparities in cystic fibrosis (CF), an autosomal recessive genetic disorder with substantial variation in disease progression and outcomes. We review disparities by race, ethnicity, socioeconomic status, geographic location, gender identity, or sexual orientation documented in the literature. We outline the mechanisms that generate and perpetuate such disparities across levels and domains of influence and assess the implications of this evidence. We then recommend strategies for improving equity in CF outcomes, drawing on recommendations for the general population and considering approaches specific to people living with CF.

Center-level self-study identifies opportunities to advance equity in cystic fibrosis clinical trial participation

Clinical trials are a necessary tool for evaluating the effectiveness of newly developed treatments and interventions for cystic fibrosis (CF). Prior work demonstrated a proportional underrepresentation of people with CF (pwCF) identifying as part of a minoritized racial or ethnic group in clinical trials. In order to establish a baseline for improvement efforts, we undertook a center-level self-study to evaluate if the racial and ethnic backgrounds of pwCF participating in clinical trials at our CF Center in New York City reflect our overall patient diversity (N = 200; 55 pwCF identifying as part of a minoritized racial or ethnic group and 145 pwCF identifying as non-Hispanic White). A smaller proportion of pwCF identifying as part of a minoritized racial or ethnic group participated in a clinical trial as compared to pwCF identifying as non-Hispanic White (21.8% vs. 35.9%, P = 0.06). A similar trend was present for pharmaceutical clinical trials (9.1% vs. 16.6%, P = 0.3). When limiting the study population to the pwCF most likely to be eligible for a CF pharmaceutical clinical trial, a larger proportion of pwCF identifying as part of a minoritized racial or ethnic group participated in a pharmaceutical clinical trial as compared to pwCF identifying as non-Hispanic White (36.4% vs. 19.6%, P = 0.2). No pwCF identifying as part of a minoritized racial or ethnic group participated in an offsite clinical trial. Efforts to improve the racial and ethnic diversity of pwCF in clinical trials, both onsite and offsite, will require a shift in how recruitment opportunities are identified and communicated to pwCF.

Socioeconomic determinants of respiratory health in patients with cystic fibrosis: implications for treatment strategies

INTRODUCTION

Great variation exists in the progression and outcomes of cystic fibrosis (CF) lung disease, due to both genetic and environmental influences. Social determinants mediate environmental exposures and treatment success; people with CF from socioeconomically disadvantaged backgrounds have worse health and die younger than those in more advantaged positions.

AREAS COVERED

This paper reviews the literature on the mechanisms that are responsible for generating and sustaining disparities in CF health, and the ways by which social determinants translate into health advantages or disadvantages in people with CF. The authors make recommendations for addressing social risk factors in CF clinical practice.

EXPERT OPINION

Socioeconomic factors are not dichotomous and their impact is felt at every step of the social ladder. CF care programs need to adopt a systematic protocol to screen for health-related social risk factors, and then connect patients to available resources to meet individual needs. Considerations such as daycare, schooling options, living and working conditions, and opportunities for physical exercise and recreation as well as promotion of self-efficacy are often overlooked. In addition, advocacy for changes in public policies on health insurance, environmental regulations, social welfare, and education would all help address the root causes of CF health inequities.

Self-management intervention to reduce pulmonary exacerbations by supporting treatment adherence in adults with cystic fibrosis: a randomised controlled trial

Introduction

Recurrent pulmonary exacerbations lead to progressive lung damage in cystic fibrosis (CF). Inhaled medications (mucoactive agents and antibiotics) help prevent exacerbations, but objectively measured adherence is low. We investigated whether a multi-component (complex) self-management intervention to support adherence would reduce exacerbation rates over 12 months.

Methods

Between October 2017 and May 2018, adults with CF (aged ≥16 years; 19 UK centres) were randomised to the intervention (data-logging nebulisers, a digital platform and behavioural change sessions with trained clinical interventionists) or usual care (data-logging nebulisers). Outcomes included pulmonary exacerbations (primary outcome), objectively measured adherence, body mass index (BMI), lung function (FEV₁) and Cystic Fibrosis Questionnaire-Revised (CFQ-R). Analyses were by intent to treat over 12 months.

Results

Among intervention (n=304) and usual care (n=303) participants (51% female, median age 31 years), 88% completed 12-month follow-up. Mean exacerbation rate was 1.63/year with intervention and 1.77/year with usual care (adjusted ratio 0.96; 95% CI 0.83 to 1.12; p=0.64). Adjusted mean differences (95% CI) were in favour of the intervention versus usual care for objectively measured adherence (9.5% (8.6% to 10.4%)) and BMI (0.3 (0.1 to 0.6) kg/m²), with no difference for %FEV₁ (1.4 (−0.2 to 3.0)). Seven CFQ-R subscales showed no between-group difference, but treatment burden reduced for the intervention (3.9 (1.2 to 6.7) points). No intervention-related serious adverse events occurred.

Conclusions

While pulmonary exacerbations and FEV₁ did not show statistically significant differences, the intervention achieved higher objectively measured adherence versus usual care. The adherence difference might be inadequate to influence exacerbations, though higher BMI and lower perceived CF treatment burden were observed.

Home-Monitoring Application for Children With Medical Complexity: A Feasibility Trial

OBJECTIVES

Mobile apps are suggested for supporting home monitoring and reducing emergency department (ED) visits and hospitalizations for children with medical complexity (CMC). None have been implemented. We sought to assess the MyChildCMC app (1) feasibility for CMC home monitoring, (2) ability to detect early deteriorations before ED and hospital admissions, and (3) preliminary impact.

METHODS

Parents of CMC (aged 1-21 years) admitted to a children's hospital were randomly assigned to MyChildCMC or usual care. MyChildCMC subjects recorded their child's vital signs and symptoms daily for 3 months postdischarge and received real-time feedback. Feasibility measures included parent's enrollment, retention, and engagement. The preliminary impact was determined by using quality of life, parent satisfaction with care, and subsequent ED and hospital admissions and hospital days.

RESULTS

A total of 62 parents and CMC were invited to participate: 50 enrolled (80.6% enrollment rate) and were randomly assigned to MyChildCMC (n = 24) or usual care (n = 26). Retention at 1 and 3 months was 80% and 74%, and engagement was 68.3% and 62.6%. Run-chart shifts in vital signs were common findings preceding admissions. The satisfaction score was 26.9 in the MyChildCMC group and 24.1 in the control group (P = .035). No quality of life or subsequent admission differences occurred between groups. The 3-month hospital days (pre-post enrollment) decreased from 9.25 to 4.54 days (rate ratio = 0.49; 95% confidence interval = 0.39-0.62; P < .001) in the MyChildCMC group and increased from 1.08 to 2.46 days (rate ratio = 2.29; 95% confidence interval = 1.47-3.56; P < .001) in the control group.

CONCLUSIONS

MyChildCMC was feasible and appears effective, with the potential to detect early deteriorations in health for timely interventions that might avoid ED and hospitalizations. A larger and definitive study of MyChildCMC's impact and sustainability is needed.

Antibiotics in Adult Cystic Fibrosis Patients: A Review of Population Pharmacokinetic Analyses

BACKGROUND

Lower respiratory tract infections are common in adult patients with cystic fibrosis (CF) and are frequently caused by Pseudomonas aeruginosa, resulting in chronic lung inflammation and fibrosis. The progression of multidrug-resistant strains of P. aeruginosa and alterations in the pharmacokinetics of many antibiotics in CF make optimal antimicrobial therapy a challenge, as reflected by high between- and inter-individual variability (IIV).

OBJECTIVES

This review provides a synthesis of population pharmacokinetic models for various antibiotics prescribed in adult CF patients, and aims at identifying the most reported structural models, covariates and sources of variability influencing the dose-concentration relationship.

METHODS

A literature search was conducted using the PubMed database, from inception to August 2020, and articles were retained if they met the inclusion/exclusion criteria.

RESULTS

A total of 19 articles were included in this review. One-, two- and three-compartment models were reported to best describe the pharmacokinetics of various antibiotics. The most common covariates were lean body mass and creatinine clearance. After covariate inclusion, the IIV (range) in total body clearance was 27.2% (10.40-59.7%) and 25.9% (18.0-33.9%) for β-lactams and aminoglycosides, respectively. IIV in total body clearance was estimated at 36.3% for linezolid and 22.4% for telavancin. The IIV (range) in volume of distribution was 29.4% (8.8-45.9%) and 15.2 (11.6-18.0%) for β-lactams and aminoglycosides, respectively, and 26.9% for telavancin. The median (range) of residual variability for all studies, using a combined (proportional and additive) model, was 12.7% (0.384-30.80%) and 0.126 mg/L (0.007-1.88 mg/L), respectively.

CONCLUSION

This is the first review that highlights key aspects of different population pharmacokinetic models of antibiotics prescribed in adult CF patients, effectively proposing relevant information for clinicians and researchers to optimize antibiotic therapy in CF.

Information needs for designing a home monitoring system for children with medical complexity

Background Children with medical complexity (CMC) are a growing population of medically fragile children with unique healthcare needs, who have recurrent emergency department (ED) and hospital admissions due to frequent acute escalations of their chronic conditions. Mobile health (mHealth) tools have been suggested to support CMC home monitoring and prevent admissions. No mHealth tool has ever been developed for CMC and challenges exist. Objective To: 1) assess information needs for operationalizing CMC home monitoring, and 2) determine technology design functionalities needed for building a mHealth application for CMC. Methods Qualitative descriptive study conducted at a tertiary care children's hospital with a purposive sample of English-speaking caregivers of CMC. We conducted 3 focus group sessions, using semi-structured, open-ended questions. We assessed caregiver's perceptions of early symptoms that commonly precede acute escalations of their child conditions, and explored caregiver's preferences on the design functionalities of a novel mHealth tool to support home monitoring of CMC. We used content analysis to assess caregivers' experience concerning CMC symptoms, their responses, effects on caregivers, and functionalities of a home monitoring tool. Results Overall, 13 caregivers of CMC (ages 18 months to 19 years, mean = 9 years) participated. Caregivers identified key symptoms in their children that commonly presented 1-3 days prior to an ED visit or hospitalization, including low oxygen saturations, fevers, rapid heart rates, seizures, agitation, feeding intolerance, pain, and a general feeling of uneasiness about their child's condition. They believed a home monitoring system for tracking these symptoms would be beneficial, providing a way to identify early changes in their child's health that could prompt a timely and appropriate intervention. Caregivers also reported their own symptoms and stress related to caregiving activities, but opposed monitoring them. They suggested an mHealth tool for CMC to include the following functionalities: 1) symptom tracking, targeting commonly reported drivers (symptoms) of ED/hospital admissions; 2) user friendly (ease of data entry), using voice, radio buttons, and drop down menus; 3) a free-text field for reporting child's other symptoms and interventions attempted at home; 4) ability to directly access a health care provider (HCP) via text/email messaging, and to allow real-time sharing of child data to facilitate care, and 5) option to upload and post a photo or video of the child to allow a visual recall by the HCP. Conclusions Caregivers deemed a mHealth tool beneficial and offered a set of key functionalities to meet information needs for monitoring CMC's symptoms. Our future efforts will consist of creating a prototype of the mHealth tool and testing it for usability among CMC caregivers.

Cystic fibrosis patient registries: A valuable source for clinical research

Cystic Fibrosis (CF) patient registries are valuable data sources for researchers studying the natural history, treatment paradigms, and long-term health outcomes of individuals with CF. In this review, we discuss the role of CF patient registries in facilitating comparative effectiveness research, particularly evaluating therapies and variation in health care delivery. We also discuss the limitations of registry-based research, particularly indication bias, as well as statistical methods that can be used to address these issues.

Comparative Effectiveness Research in Pediatric Respiratory Disease: Promise and Pitfalls

Comparative effectiveness research (CER) has become increasing central to clinical research in medicine. CER seeks to conduct clinical trials that compare different commonly used interventions in real-world settings (pragmatic clinical trials) and use a multitude of sources of evidence (including registries and cohort studies) to inform clinical decision making. CER also ensures that stakeholders (patients, families, care providers, insurers) have a voice in the research process by integrating formal stakeholder engagement as part of the research. This innovative approach to clinical research has distinct benefits and pitfalls. This review first defines what CER is and then describes some of its benefits and then pitfalls. The focus is on the role of CER in pediatrics.

Electronic health records as a tool for recruitment of participants' clinical effectiveness research: lessons learned from tobacco cessation

Translating tobacco dependence treatments that are effective in research settings into real-world clinical settings remains challenging. Electronic health record (EHR) technology can facilitate this process. This paper describes the accomplishments and lessons learned from a translational team science (clinic/research) approach to the development of an EHR tool for participant recruitment and clinic engagement in tobacco cessation research. All team stakeholders-research, clinical, and IT-were engaged in the design and planning of the project. Results over the first 17 months of the study showed that over one half of all smokers, coming in for any type of clinic appointment, were offered participation in the study, a very high level of adherent use of the EHR. Study recruitment over this period was 1,071 individuals, over 12 % of smokers in the participating clinics.

Do patients who take part in stroke research differ from non-participants? Implications for generalizability of results

BACKGROUND

Stroke is one of the most disabling neurological conditions. Clinical research is vital for expanding knowledge of treatment effectiveness among stroke patients. However, evidence begins to accumulate that stroke patients who take part in research represent only a small proportion of all stroke patients. Research participants may also differ from the broader patient population in ways that could potentially distort treatment effects reported in therapeutic trials. The aims of this study were to estimate the proportion of stroke patients who take part in clinical research studies and to compare demographic and clinical profiles of research participants and non-participants.

METHODS

5,235 consecutive patients admitted to the Stroke Care Unit of the Royal Melbourne Hospital, Melbourne, Australia, for stroke or transient ischaemic attack between January 2004 and December 2011 were studied. The study used cross-sectional design. Information was collected on patients' demographic and socio-economic characteristics, risk factors, and comorbidities. Associations between research participation and patient characteristics were initially assessed using χ(2) or Mann-Whitney tests, followed by a multivariable logistic regression analysis. The logistic regression analysis was carried out using generalised estimating equations approach, to account for patient readmissions during the study period.

RESULTS

558 Stroke Care Unit patients (10.7%) took part in at least one of the 33 clinical research studies during the study period. Transfer from another hospital (OR = 0.35, 95% CI 0.22-0.55), worse premorbid function (OR = 0.61, 95% CI 0.54-0.70), being single (OR = 0.61, 95% CI 0.44-0.84) or widowed (OR = 0.77, 95% CI 0.60-0.99), non-English language (OR = 0.67, 95% CI 0.53-0.85), high socio-economic status (OR = 0.74, 95% CI 0.59-0.93), residence outside Melbourne (OR = 0.75, 95% CI 0.60-0.95), weekend admission (OR = 0.78, 95% CI 0.64-0.94), and a history of atrial fibrillation (OR = 0.79, 95% CI 0.63-0.99) were associated with lower odds of research participation. A history of hypertension (OR = 1.50, 95% CI 1.08-2.07) and current smoking (OR = 1.23, 95% CI 1.01-1.50) on the other hand were associated with higher odds of research participation.

CONCLUSIONS

The results of this study indicate that stroke patients who take part in clinical research do not represent 'typical' patient admitted to a stroke unit. The imbalance of prognostic factors between stroke participants and non-participants has serious implications for interpretation of research findings reported in stroke literature. This study provides insights into clinical, demographic, and socio-economic characteristics of stroke patients that could potentially be targeted to enhance generalizability of stroke research studies. Given the imbalance of prognostic factors between research participants and non-participants, future studies need to examine differences in stroke outcomes of these groups of patients.

Pediatric hospital medicine and children with medical complexity: past, present, and future

Children with medical complexity, regardless of underlying diagnoses, share similar functional and resource use consequences, including: intensive service needs, reliance on technology, polypharmacy, and/or home care or congregate care to maintain a basic quality of life, high health resource utilization, and, an elevated need for care coordination. The emerging field of complex care is focused on the holistic medical care of these children, which requires both broad general pediatrics skills and specific expertise in care coordination and communication with patients, families, and other medical and non-medical care providers. Many pediatric hospitalists have developed an interest in care coordination for CMC, and pediatric hospitalists are in an ideal location to embrace complex care. As a result of these factors, complex care has emerged as a field with many pediatric hospitalists at the helm, in arenas ranging from clinical care of these patients, research into their care, and education of future providers. The objective of this section of the review article is to outline the past, present, and possible future of children with medical complexity within several arenas in the field of pediatric hospital medicine, including practice management, clinical care, research, education, and quality improvement.

Nongenetic influences on cystic fibrosis outcomes

PURPOSE OF REVIEW

Despite dramatic improvements over the last several decades, tremendous variation exists in cystic fibrosis (CF) health outcomes. Genetic explanations for variations in disease progression are a promising source of information regarding disease biology and pathophysiology, but an understanding of nongenetic factors provides more immediate tools for improving disease outcomes.

RECENT FINDINGS

The clinical course of CF for any individual with CF is determined by the interaction of genetic endowment (including CFTR and modifier genes), the physical environment (including environmental tobacco smoke, outdoor pollution, and pathogenic microorganisms), the sociodemographic, cultural, and family context (which mediates stress, social support, and disease self-management skills), and variations in delivery and acceptance of healthcare treatments. The evidence linking socioeconomic status (SES) with CF outcomes continues to be strong, and appears to be primarily due to associations with environmental and sociocultural stressors and disease-management behaviors rather than barriers in access to healthcare.

SUMMARY

Attempts to eliminate detrimental environmental exposures, improve disease self-management skills, and ensure consistently optimal healthcare practices will likely decrease variations in outcomes including SES-related disparities. Low SES is an important marker of adverse exposures and outcomes which are present throughout the CF population.

An overview of international literature from cystic fibrosis registries. Part 3. Disease incidence, genotype/phenotype correlation, microbiology, pregnancy, clinical complications, lung transplantation, and miscellanea

This is the third article related to a review of the literature based on data from national cystic fibrosis (CF) patient registries up to June 2008 and covering a total of 115 published studies. It focuses on several topics: CF incidence, genotype/phenotype correlation, microbiology, pregnancy/paternity, clinical complications, lung transplantation, and others. Seventy seven papers meeting the inclusion criteria were found to be related to the topics listed above. Another seven studies, already evaluated in previous papers of this series, were recalled for specific topics. Incidence is described by several studies, results being quite different from one country to another and quite inhomogeneous among regions within the same country. Studies on genetics address the genotype/phenotype correlation and look for a predictive value of CFTR mutations in terms of clinical outcome, with controversial results. Papers on microbiology describe the clinical relevance of different pathogens and their role in the progress of CF lung disease. A few articles give information on the features of CF women undergoing a pregnancy and try to identify the ones associated with a better outcome. Studies on clinical complications discuss prevalence and the role of haemoptysis, pneumothorax, CF related diabetes, ABPA and cancer. Papers on lung transplantation focus on models able to improve the selection criteria for transplantation candidates and the factors linked to post transplantation survival. Finally, several studies deal with a number of interesting topics related to CF epidemiology: clinical trial methodology, quality of care comparison among countries and centers, relationship between diagnosis and age/gender, and evaluation of pharmacological therapy. On the whole, CF Registries have already contributed to important advances in the knowledge of the natural history of CF, establishing the foundations for future improvement in CF research and care.

Long-term comparative trial of two different physiotherapy techniques; postural drainage with percussion and autogenic drainage, in the treatment of cystic fibrosis

In N. America, over the past decade, various airway clearance techniques (ACT) have been introduced for the treatment of cystic fibrosis (CF). We hypothesized that autogenic drainage (AD), an ACT developed in Belgium would be as effective as postural drainage with percussion (PD) in treating patients with CF.

METHODS

Thirty-six CF patients, aged 12-18 years, with Shwachman score 65-98, were enrolled in a 2-year cross-over trial. Patients were matched as pairs and members of each pair were randomly assigned to two groups. For the first study year, Group A performed PD while Group B performed AD. At the end of 1 year Groups A and B crossed over physiotherapy techniques. Clinical status and pulmonary function (FVC, FEV(1), FEF(25-75)) were measured at 3 monthly intervals. Only results from the first year of the study are reported, as 10 out of 17 patients who had completed performing AD for the first year refused to change back to PD for the second year.

RESULTS

During the first year of the study, both the AD and PD groups demonstrated improved pulmonary function with no significant difference between the two groups. Change in FVC and FEV(1) percent predicted for Groups A and B was 0.47 ± 1.65(se) versus 2.35 ± 1.51(se) and 2.09 ± 2.2(se) versus 0.92 ± 2.25(se). However, CF patients exhibited a marked preference for the AD technique. Results suggest that both AD and PD are effective methods of performing physiotherapy for CF patients and that the benefits of either technique are enhanced by measures which encourage adherence.

Safety and efficacy of long-acting injectable risperidone in daily practice: an open-label, noninterventional, prospective study in schizophrenia and related disorders

This postauthorization safety study evaluated the long-term safety, tolerability, and efficacy of risperidone long-acting injectable (RLAI) in routine clinical practice. In this 6-month, multicenter, European, naturalistic study, patients were included if, during routine clinical practice, long-term antipsychotic therapy with RLAI was deemed necessary by the treating physician. Efficacy measures included Clinical Global Impression-Severity and Global Assessment of Functioning. Safety was evaluated by recording treatment-emergent adverse events (AE). RLAI was initiated in 5134 patients (aged 14-94 years); predominantly male (58.6%) with paranoid schizophrenia (69.8%). RLAI initial doses were 25 mg every 2 weeks (37.0% patients), 37.5 mg (18.0%), and 50 mg (44.4%). Treatment was completed by 4314 patients (84.0%). RLAI was discontinued on account of loss to follow-up (n=346; 6.7%), insufficient response (n=116; 2.3%), and AEs (n=106; 2.1%). Clinical Global Impression-Severity significantly improved from baseline to endpoint (P<0.001). Patient functioning on the Global Assessment of Functioning scale also significantly improved from baseline to endpoint (45.4 + or - 16.0 vs. 62.4 + or - 17.7, respectively, P<0.001). Treatment-emergent AEs were recorded by 1018 (20%) of patients. AEs occurring in > or = 5% of patients were akathisia, extrapyramidal disorders, depression, psychotic disorder, anxiety, and weight gain. Serious AEs were reported by 384 (8%) patients. This study confirms good safety, tolerability, and efficacy with RLAI in routine clinical practice.

Lessons learned from a randomized trial of airway secretion clearance techniques in cystic fibrosis

RATIONALE

Airway secretion clearance therapies are a cornerstone of cystic fibrosis care, however longitudinal comparative studies are rare. Our objectives were to compare three therapies [postural drainage and percussion: (postural drainage), flutter device (FD), and high frequency chest wall oscillation: (vest)], by studying (1) change in pulmonary function; (2) time to need for intravenous (IV) antibiotics, (3) use of pulmonary therapies, (4) adherence to treatment, (5) treatment satisfaction, and (6) quality of life.

METHODS

Participants were randomly assigned to one of three therapies twice daily. Clinical outcomes were assessed quarterly over 3 years.

RESULTS

Enrollment goals were not met, and withdrawal rates were high, especially in postural drainage (51%) and FD (26%), compared to vest (9%), resulting in early termination. FEV(1) decline, time to need IV antibiotics, and other pulmonary therapies were not different. The annual FEF(25-75%) predicted rate of decline was greater in those using vest (P = 0.02). Adherence was not significantly different (P = 0.09). Overall treatment satisfaction was higher in vest and FD than in postural drainage (P < 0.05). Health-related quality of life was not different. The rate of FEV(1) decline was 1.23% predicted/year.

CONCLUSIONS

The study was ended early due to dropout and smaller than expected decline in FEV(1). Patients were more satisfied with vest and FD. The longitudinal decline in FEF(25-75%) was faster in vest; we found no other difference in lung function decline, taken together this warrants further study. The slow decline in FEV(1) illustrates the difficulty with FEV(1) decline as a clinical trial outcome.

Clinical trials in cystic fibrosis

In patients with cystic fibrosis (CF), clinical trials are of paramount importance. Here, the current status of drug development in CF is discussed and future directions highlighted. Methods for pre-clinical testing of drugs with potential activity in CF patients including relevant animal models are described. Study design options for phase II and phase III studies involving CF patients are provided, including required patient numbers, safety issues and surrogate end point parameters for drugs, tested for different disease manifestations. Finally, regulatory issues for licensing new therapies for CF patients are discussed, including new directives of the European Union and the structure of a European clinical trial network for clinical studies involving CF patients is proposed.

Laboratory parameter profiles among patients with cystic fibrosis

BACKGROUND

Clinical trials in cystic fibrosis (CF) currently use laboratory-specific reference ranges to evaluate chemistry and hematology measurements. Laboratory-specific normal reference ranges may not accurately reflect what is abnormal but clinically insignificant among CF patients.

METHODS

To address this concern, data from the Phase III trial of inhaled tobramycin in CF patients was used to describe the distribution and variability of laboratory parameters. The laboratory specimens were analyzed at a central laboratory after being obtained at baseline and throughout the 24-week trial.

RESULTS

At the time of entry into the clinical trial, 91% (463 of 508) of patients had at least a single value outside the normal range. Liver function tests (AST, ALT) were above the normal range in 16% and 12% of the patients respectively, with 2.4% of patients having an AST>2.0 times the upper limit of normal. Of the 243 patients on placebo, 242 (99.6%) had at least one laboratory parameter that changed from normal to abnormal during the 24-week follow-up period. Of those same placebo patients, 11.5% (N=28) had a laboratory parameter change from a Common Toxicity Criteria (CTC) grade 0 to grade 2 or higher during follow-up.

CONCLUSIONS

Patients with CF frequently have laboratory values outside the normal range and have significant longitudinal variability of laboratory values. Interpretation of adverse events in the clinical trial setting may be complicated by the underlying high rates of some laboratory abnormalities in the CF population. This data was presented in poster format at the American Thoracic Society International Conference, Atlanta, USA, 2002, appearing subsequently in the Conference proceedings [Goss CH, Mayer-Hamblett N, Yunker A, Waltz DA, Kronmal RA, Ramsey BW. Laboratory parameter profiles among patients with cystic fibrosis. Am J Rep Crit Care Med 2002;165(8):A283].

Respiratory adverse event profiles in cystic fibrosis placebo subjects in short- and long-term inhaled therapy trials

The frequency and nature of adverse events (AEs) are important safety endpoints in clinical trials of therapies for cystic fibrosis (CF) subjects, yet published tables of background AE rates in the CF population are not readily available. Our objective in this study was to produce tables of respiratory AE rates for placebo subjects (pediatric and adult) for inhaled therapy trials in CF subjects. Respiratory AE rates in inhaled therapy trials were computed by combining data on placebo subjects from early-phase dosing studies and middle/late-phase studies, where placebo consisted of 4 or 5 mL of inhaled saline solution. AE rates were computed as number of events divided by number of placebo-subject days of observation, and 95% confidence intervals were computed based on a Poisson model. AEs were categorized as both broad (e.g., respiratory, reactive airway disease) and specific (e.g., cough, chest tightness, hemoptysis). In short-term studies, respiratory AE rates (95% confidence interval) were 1.1(0.7, 1.6)/person-week and 1.0(0.7, 1.4)/person-week in pediatric and adult subjects, respectively. In long-term studies, respiratory AE rates were 1.7(1.6, 1.8)/person-month and 2.2(2.1, 2.3)/person-month in pediatric and adult subjects, respectively. Stepwise Poisson models were fit to determine if baseline covariates were important in predicting AE rates. Forced expiratory volume in one second (FEV(1)) percent of predicted and age in short-term studies, and FEV(1) percent predicted and gender in long-term studies were statistically important in predicting respiratory AE rates. Although these variables were statistically significant, the models' predictive abilities were low, with adjusted R(2)'s of 0.06 and 0.12 in the short- and long-term studies, respectively. Combining placebo-subject AE data recorded from multiple CF clinical trials yields better estimates of true rates of occurrence in the CF population. The tables published from this study can be used to assist those charged with safety monitoring in CF clinical trials.