A randomized trial of inhaled cyclosporine in lung-transplant recipients

Antibody-engineered nanoparticles selectively inhibit mesenchymal cells isolated from patients with chronic lung allograft dysfunction

AIMS

Chronic lung allograft dysfunction represents the main cause of death after lung transplantation, and so far there is no effective therapy. Mesenchymal cells (MCs) are primarily responsible for fibrous obliteration of small airways typical of chronic lung allograft dysfunction. Here, we engineered gold nanoparticles containing a drug in the hydrophobic section to inhibit MCs, and exposing on the outer hydrophilic surface a monoclonal antibody targeting a MC-specific marker (half-chain gold nanoparticles with everolimus).

MATERIALS & METHODS

Half-chain gold nanoparticles with everolimus have been synthesized and incubated with MCs to evaluate the effect on proliferation and apoptosis.

RESULTS & DISCUSSION

Drug-loaded gold nanoparticles coated with the specific antibody were able to inhibit proliferation and induce apoptosis without stimulating an inflammatory response, as assessed by in vitro experiments.

CONCLUSION

These findings demonstrate the effectiveness of our nanoparticles in inhibiting MCs and open new perspectives for a local treatment of chronic lung allograft dysfunction.

Calcineurin inhibitors: 40 years later, can't live without

Calcineurin inhibitors (CNIs) revolutionized the field of organ transplantation and remain the standard of care 40 years after the discovery of cyclosporine. The early impressive results of cyclosporine in kidney transplant recipients led to its subsequent use in other organ transplant recipients and for treatment of a variety of autoimmune diseases as well. In this review, we examine the discovery of CNIs, their mechanism of action, preclinical and clinical studies with CNIs, and the usage of CNIs in nontransplant recipients. We review the mechanisms of renal toxicity associated with CNIs and the recent efforts to avoid or reduce usage of these drugs. Although minimization strategies are possible, safe, and of potential long-term benefit, complete avoidance of CNIs has proven to be more challenging than initially thought.

Ciclosporin use during pregnancy

Ciclosporin (cyclosporine) is an immunosuppressive drug first approved for use in organ transplantation to prevent rejection. Ciclosporin is also known to be used for the treatment of psoriasis, rheumatoid arthritis, systemic lupus erythematosus and inflammatory bowel disease, among other indications. While it is recommended that all medications that are not absolutely necessary should be avoided during pregnancy, this may not be an option for many women whose quality of life is significantly impacted without treatment, or for those who must continue immunosuppressive therapy to avoid organ rejection. The purpose of this review is to provide a comprehensive report from the literature of ciclosporin exposure during pregnancy. PubMed, MEDLINE and the Cochrane Database of Systematic Reviews were searched for English-language articles published from 1970 to 2012 that included reports of pregnant women treated at any time during pregnancy with ciclosporin. On an initial search, it was evident that much of the available information is limited to pregnancy after transplant, which suggests that ciclosporin use during pregnancy appears to be associated with premature delivery and low birthweight infants. Comorbidities such as hypertension, pre-eclampsia and gestational diabetes mellitus are also reported at higher incidences than the general population. Medical literature concerning women with autoimmune disorders exposed to ciclosporin during pregnancy are currently limited to case reports and registry data, and, as such, it is difficult to determine if any risks associated with ciclosporin therapy during pregnancy are due to exposure to the drug alone or to pre-existing maternal comorbidities. The literature suggests that ciclosporin therapy during pregnancy should be carefully considered by the treating physician, but may be a safe alternative for patients with autoimmune disease refractory to conventional treatment. Continued monitoring of this patient population remains a key component to understanding the risk factors associated with ciclosporin exposure during pregnancy.

Immunosuppressive drug therapy for preventing rejection following lung transplantation in cystic fibrosis

BACKGROUND

For patients with cystic fibrosis and advanced pulmonary damage, lung transplantation is an available and viable option. However, graft rejection is an important potential consequence after lung transplantation. Immunosuppressive therapy is needed to prevent episodes of graft rejection and thus subsequently reduce morbidity and mortality in this population. There are a number of classes of immunosuppressive drugs which act on different components of the immune system. There is considerable variability in the use of immunosuppressive agents after lung transplantation in cystic fibrosis. While much of the research in immunosuppressive drug therapy has focused on the general population of lung transplant recipients, little is known about the comparative effectiveness and safety of these agents in patients with cystic fibrosis.

OBJECTIVES

To assess the effects of individual drugs or combinations of drugs compared to placebo or other individual drugs or combinations of drugs in preventing rejection following lung transplantation in patients with cystic fibrosis.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register and scanned references of the potentially eligible study. We also searched the www.clinicaltrials.gov trials registry to obtain information on unpublished and ongoing studies.Date of latest search: 22 August 2013.

SELECTION CRITERIA

Randomised and quasi-randomised studies.

DATA COLLECTION AND ANALYSIS

We independently assessed the studies identified from our searches for inclusion in the review. Should eligible studies be identified and included in future updates of the review, we will independently extract data and assess the risk of bias.

MAIN RESULTS

While two studies met our inclusion criteria, we did not include them in the review because the investigators of the studies did not report any information specific to patients with cystic fibrosis. Our attempts to obtain this information have not yet been successful. We will include any provided data in future updates of the review.

AUTHORS' CONCLUSIONS

The lack of currently available evidence makes it impossible to make conclusions about the comparative efficacy and safety of the various immunosuppressive drugs among patients with cystic fibrosis after lung transplantation. A recent Cochrane review comparing tacrolimus with cyclosporine in all patients with lung transplantation (not restricted to patients with cystic fibrosis) reported no significant difference in mortality and risk of acute rejection. However, tacrolimus use was associated with lower risk of broncholitis obliterans syndrome and arterial hypertension and higher risk of diabetes mellitus. It should be noted that this review contained only a small number of included studies (n = 3) with a high risk of bias. Additional randomised studies are required to provide evidence for the benefit and safety of the use of immunosuppressive therapy among patients with cystic fibrosis after lung transplantation.

Managing bronchiolitis obliterans syndrome (BOS) and chronic lung allograft dysfunction (CLAD) in children: what does the future hold?

The success of pediatric lung transplantation continues to be limited by long-term graft dysfunction. Historically this has been characterized as an obstructive spirometric defect in the form of the bronchiolitis obliterans syndrome (BOS). It is recognized, however, that this does not reflect many of the other acknowledged etiologies of chronic lung dysfunction-noting it is the sum of the parts that contribute to respiratory morbidity and mortality after transplant. The term chronic lung allograft dysfunction (CLAD) has been coined to reflect these other entities and, in particular, a group of relatively recently described lung disorders called the restrictive allograft syndrome (RAS). RAS is characterized by a restrictive spirometric defect. Although these entities have not yet been studied in a pediatric setting their association with poor compliance, antibody-mediated rejection (AMR), and post-infectious lung damage (particularly viral) warrants attention by pediatric lung transplant teams. Current therapy for the BOS subset of CLAD is otherwise limited to changing immunosuppressants and avoiding excessive infectious risk by avoiding over-immunosuppression. Long-term macrolide therapy in lung transplantation is not of proven efficacy. Reviewing previous BOS studies to explore restrictive spirometric cases and joint projects via groups like the International Pediatric Lung Transplant Collaborative will be the way forward to solve this pressing problem.

Lung deposition and pharmacokinetics of nebulized cyclosporine in lung transplant patients

BACKGROUND

Inhaled cyclosporine (CsA) is being investigated as a prophylaxis for lung transplant rejection. Lung deposition and systemic exposure of nebulized CsA in lung transplant patients was evaluated as part of the Phase 3 cyclosporine inhalation solution (CIS) trial (CYCLIST).

METHODS

Ten patients received 300 mg of CIS (62.5 mg/mL CsA in propylene glycol) admixed with 148 MBq of Tc-DTPA (technetium-99m bound to diethylenetriaminepentaacetic acid) administered using a Sidestream(®) disposable jet nebulizer. Deposition was assessed using a dual-headed gamma camera. Blood samples were collected over a 24-hr time period after aerosol dosing and analyzed for CsA levels. A pharmacokinetic analysis of the resulting blood concentration versus time profiles was performed.

RESULTS

The average total deposited dose was 53.7 ± 12.7 mg. Average pulmonary dose was 31.8 ± 16.3 mg, and stomach dose averaged 15.5 ± 11.1 mg. Device performance was consistent, with breathing maneuvers influencing dose variation. Predose coaching with five of 10 patients reduced stomach deposition (22.6 ± 11.2 vs. 8.3 ± 5.2 mg; p=0.03). Blood concentrations declined quickly from a maximum of 372 ± 140 ng/mL to 15.3 ± 9.7 ng/mL at 24 hr post dose. Levels of AUC(0-24) [area under the concentration vs. time curve from 0 to 24 hr] averaged 1,493 ± 746 ng hr/mL. On a three times per week dose regimen, this represents <5% of the weekly systemic exposure of twice per day oral administration.

CONCLUSIONS

Substantial doses of CsA can be delivered to the lungs of lung transplant patients by inhaled aerosol. Systemic levels are small relative to typical oral CsA administration.

Lung transplantation

Lung transplantation may be the only intervention that can prolong survival and improve quality of life for those individuals with advanced lung disease who are acceptable candidates for the procedure. However, these candidates may be extremely ill and require ventilator and/or circulatory support as a bridge to transplantation, and lung transplantation recipients are at risk of numerous post-transplant complications that include surgical complications, primary graft dysfunction, acute rejection, opportunistic infection, and chronic lung allograft dysfunction (CLAD), which may be caused by chronic rejection. Many advances in pre- and post-transplant management have led to improved outcomes over the past decade. These include the creation of sound guidelines for candidate selection, improved surgical techniques, advances in donor lung preservation, an improving ability to suppress and treat allograft rejection, the development of prophylaxis protocols to decrease the incidence of opportunistic infection, more effective therapies for treating infectious complications, and the development of novel therapies to treat and manage CLAD. A major obstacle to prolonged survival beyond the early post-operative time period is the development of bronchiolitis obliterans syndrome (BOS), which is the most common form of CLAD. This manuscript discusses recent and evolving advances in the field of lung transplantation.

Site-specific immunosuppression in vascularized composite allotransplantation: prospects and potential

Skin is the most immunogenic component of a vascularized composite allograft (VCA) and is the primary trigger and target of rejection. The skin is directly accessible for visual monitoring of acute rejection (AR) and for directed biopsy, timely therapeutic intervention, and management of AR. Logically, antirejection drugs, biologics, or other agents delivered locally to the VCA may reduce the need for systemic immunosuppression with its adverse effects. Topical FK 506 (tacrolimus) and steroids have been used in clinical VCA as an adjunct to systemic therapy with unclear beneficial effects. However, there are no commercially available topical formulations for other widely used systemic immunosuppressive drugs such as mycophenolic acid, sirolimus, and everolimus. Investigating the site-specific therapeutic effects and efficacy of systemically active agents may enable optimizing the dosing, frequency, and duration of overall immunosuppression in VCA with minimization or elimination of long-term drug-related toxicity.

Monitoring of nonsteroidal immunosuppressive drugs in patients with lung disease and lung transplant recipients: American College of Chest Physicians evidence-based clinical practice guidelines

OBJECTIVES

Immunosuppressive pharmacologic agents prescribed to patients with diffuse interstitial and inflammatory lung disease and lung transplant recipients are associated with potential risks for adverse reactions. Strategies for minimizing such risks include administering these drugs according to established, safe protocols; monitoring to detect manifestations of toxicity; and patient education. Hence, an evidence-based guideline for physicians can improve safety and optimize the likelihood of a successful outcome. To maximize the likelihood that these agents will be used safely, the American College of Chest Physicians established a committee to examine the clinical evidence for the administration and monitoring of immunosuppressive drugs (with the exception of corticosteroids) to identify associated toxicities associated with each drug and appropriate protocols for monitoring these agents.

METHODS

Committee members developed and refined a series of questions about toxicities of immunosuppressives and current approaches to administration and monitoring. A systematic review was carried out by the American College of Chest Physicians. Committee members were supplied with this information and created this evidence-based guideline.

CONCLUSIONS

It is hoped that these guidelines will improve patient safety when immunosuppressive drugs are given to lung transplant recipients and to patients with diffuse interstitial lung disease.

Managing complications following lung transplantation

Lung transplantation has become a proven therapeutic option for patients with end-stage lung disease, extending life and providing improved quality of life to those who otherwise would continue to be breathless and oxygen-dependent. Over the past 20 years, considerable experience has been gained in understanding the multitude of medical and surgical issues that impact upon patient survival. Today, clinicians have an armamentarium of tools to manage diverse problems such as primary graft dysfunction, acute and chronic allograft rejection, airway anastomotic issues, infectious complications, renal dysfunction, diabetes and osteoporosis, hematological and gastrointestinal problems, malignancy, and other unique issues that confront immunosuppressed solid organ transplant recipients.

State of progress in treating cystic fibrosis respiratory disease

Since the discovery of the gene associated with cystic fibrosis (CF), there has been tremendous progress in the care of patients with this disease. New therapies have entered the market and are part of the standard treatment of patients with CF, and have been associated with marked improvement in survival. Now there are even more promising therapies directed at different components of the pathophysiology of this disease. In this review, our current knowledge of the pathophysiology of lung disease in patients with CF is described, along with the current treatment of CF lung disease, and the therapies in development that offer great promise to our patients.

Advances in immunosuppression after lung transplantation

Immunosuppression in transplantation has experienced changes in recent years as a result of the introduction of new drugs that act upon the different pathways of the host immune response with the purpose of securing more individualized immune suppression, with fewer side effects. Although following in the steps of other solid organ transplant modalities, lung transplantation, because of its special characteristics, has not yielded similar middle- and long-term results. Improved understanding of the underlying rejection mechanisms, the pharmacodynamic control of drugs, new administration routes designed to reduce the side effects, and new drug substances or immune modulating processes will all contribute to improve the expectations associated to lung transplantation in the near future.

Time to explore preventive and novel therapies for bronchiolitis obliterans syndrome after allogeneic hematopoietic stem cell transplantation

Although allogeneic hematopoietic stem cell transplant (allo-HSCT) is performed to treat otherwise incurable and fatal diseases, transplantation itself can lead to life-threatening complications due to organ damage. Pulmonary complications remain a significant barrier to the success of allo-HSCT. Lung injury, a frequent complication after allo-HSCT, and noninfectious pulmonary deaths account for a significant proportion of non-relapse mortality. Bronchiolitis obliterans syndrome (BOS) is a common and potentially devastating complication. BOS is now considered a diagnostic criterion of chronic graft-versus-host-disease (cGVHD), and National Institutes of Health (NIH) consensus has been published to establish guidelines for diagnosis and monitoring of BOS. It usually occurs within the first 2 years but may develop as late as 5 years after transplantation. Recent prevalence estimates suggest that BOS is likely underdiagnosed, and when severe BOS does occur, current treatments have been largely ineffective. Prevention and effective novel approaches remain the primary tools in the clinician's arsenal in managing BOS. This article provides an overview of the currently available and novel strategies for BOS, and we also discuss specific preventive interventions to reduce severe BOS after allo-HSCT. Therapeutic trials continue to be needed for this orphan disease.

Bronchiolitis obliterans syndrome: the final frontier for lung transplantation

Bronchiolitis obliterans syndrome (BOS) is a form of chronic lung allograft dysfunction that affects a majority of lung transplant recipients and is the principal factor limiting long-term transplant survival. BOS is characterized by progressive airflow obstruction unexplained by acute rejection, infection, or other coexistent condition. Although BOS is a proven useful clinical syndrome that identifies patients at increased risk for death, its clinical course and underlying causative factors are now recognized to be increasingly heterogeneous. Regardless of the clinical history, the primary pathologic correlate of BOS is bronchiolitis obliterans, a condition of intraluminal airway fibrosis. This article highlights the body of developing research illustrating the mechanisms by which BOS is mediated, including alloimmune reactivity, the emerging roles of humoral and autoimmunity, activation of innate immune cells, and response to nonimmune-related allograft insults, such as infection and aspiration. In addition, we underscore emerging clinical implications and promising future translational research directions that have the potential to advance our knowledge and improve patient outcomes.

Diagnosis and treatment of pulmonary chronic GVHD: report from the consensus conference on clinical practice in chronic GVHD

This consensus statement established under the auspices of the German working group on BM and blood stem cell transplantation (DAG-KBT), the German Society of Hematology and Oncology (DGHO), the Austrian Stem Cell Transplant Working Group, the Swiss Blood Stem Cell Transplantation Group (SBST) and the German-Austrian Pediatric Working Group on SCT (Päd-Ag-KBT) summarizes current evidence for diagnosis, immunosuppressive and supportive therapy to provide practical guidelines for the care and treatment of patients with pulmonary manifestations of chronic GVHD (cGVHD). Pulmonary cGVHD can present with obstructive and/or restrictive changes. Disease severity ranges from subclinical pulmonary function test (PFT) impairment to respiratory insufficiency with bronchiolitis obliterans being the only pulmonary complication currently considered diagnostic of cGVHD. Early diagnosis may improve clinical outcome, and regular post-transplant follow-up PFTs are recommended. Diagnostic work-up includes high-resolution computed tomography, bronchoalveolar lavage and histology. Topical treatment is based on inhalative steroids plus beta-agonists. Early addition of azithromycin is suggested. Systemic first-line treatment consists of corticosteroids plus, if any, continuation of other immunosuppressive therapy. Second-line therapy and beyond includes extracorporeal photopheresis, mammalian target of rapamycin inhibitors, mycophenolate, etanercept, imatinib and TLI, but efficacy is limited. Clinical trials are urgently needed to improve understanding and treatment of this deleterious complication.

Polarized alloantigen presentation by airway epithelial cells contributes to direct CD8+ T cell activation in the airway

Activated T lymphocytes are abundant in the airway during lung allograft rejection. Based on respiratory viral studies, it is the current paradigm that T cells cannot divide in the airway, and that their accumulation in the lumen of the respiratory tract is the exclusive result of recruitment from other sites, such as mediastinal lymph nodes. Here, we show that CD8(+) T cell activation and proliferation can occur in the airway after orthotopic lung transplantation. We also demonstrate that airway epithelium expresses major histocompatibility class I predominantly on the apical surface, both in vitro and in vivo, and initiates CD8(+) T cell responses in a polarized fashion, favoring luminal activation. Our data identify a unique site for CD8(+) T cell activation after lung transplantation, and suggest that attenuating these responses may provide a clinically relevant target.

Conventional and novel approaches to immunosuppression

Immunosuppressive therapy has contributed significantly to improved survival after solid organ transplantation. Nevertheless, treatment-related adverse events and persistently high risk of chronic graft rejection remain major obstacles to long-term survival after lung transplantation. The development of new agents, refinements in techniques to monitor immunosuppression, and enhanced understanding of transplant immunobiology are essential for further improvements in outcome. In this article, conventional immunosuppressive regimens, novel approaches to preventing graft rejection, and investigational agents for solid organ transplantation are reviewed.

Survival and quality of life of patients undergoing lung transplant

Lung transplant offers the hope of prolonged survival and significant improvement in quality of life to patients with advanced lung disease. However, the medical literature lacks strong evidence and shows conflicting information regarding the effects of lung transplantation on these outcomes. Tools that integrate survival and quality-of-life information allow for more comprehensive evaluations of the benefits and risks of lung transplant. Higher-quality information leads to improved knowledge and more-informed decision making.

A review of bronchiolitis obliterans syndrome and therapeutic strategies

Lung transplantation is an important treatment option for patients with advanced lung disease. Survival rates for lung transplant recipients have improved; however, the major obstacle limiting better survival is bronchiolitis obliterans syndrome (BOS). In the last decade, survival after lung retransplantation has improved for transplant recipients with BOS. This manuscript reviews BOS along with the current therapeutic strategies, including recent outcomes for lung retransplantation.

Lung transplantation in autoimmune diseases

In the last 45 years, lung transplantation has evolved from its status as a rare extreme form of surgical therapy for the treatment of advanced lung diseases to an accepted therapeutic option for select patients. Although pulmonary fibrosis and pulmonary vascular diseases are important indications for lung transplantation, only a small percentage of transplants are performed in patients with collagen vascular diseases. The reasons for this low number are multifactorial. This article reviews issues relevant to all lung transplant candidates and recipients as well as those specific to patients with autoimmune diseases.

Safety and toxicology of cyclosporine in propylene glycol after 9-month aerosol exposure to beagle dogs

BACKGROUND

Cyclosporine inhalation solution (CIS) delivered via nebulization is under evaluation for the prevention of chronic rejection post-lung transplant. A 300-patient randomized, controlled clinical trial (CYCLIST) is expected to be completed late in 2011. In support of this trial, a chronic inhalation toxicology study in dogs has been completed.

METHODS

To mimic the clinical setting, animals (four/sex/dose plus two/sex/dose in the control and high dose recovery groups) were exposed to aerosolized CIS, via nose-only exposure, three times per week for 9 months at targeted inhaled doses of 0 (air), 4, 12, and 24 mg/kg. In addition, the potential for persistence or reversibility of any toxic effects were assessed after a 6-week recovery period. The toxicological endpoints included clinical observations, body-weight, food consumption, toxicokinetics, clinical chemistry, and histopathology.

RESULTS

All dogs receiving CIS completed the study with the only consistent observations being excessive salivation and changes in minute ventilation. There was no limiting lung or systemic toxicity associated with exposure to CIS, and the only possible drug-related effect was an observation of benign fibroadenoma tissue in the mammary glands of the high-dose female recovery group. Toxicokinetic data showed that cyclosporine is initially absorbed rapidly with little drug remaining in lung tissue or blood 24 h after the end of dosing.

CONCLUSION

The study supports the pulmonary and systemic safety of aerosolized CIS at expected lung dose levels/kg of up to 12 times greater than the average dose patients are receiving in the CYCLIST trial.

Aerosol drug delivery: developments in device design and clinical use

Aerosolised drugs are prescribed for use in a range of inhaler devices and systems. Delivering drugs by inhalation requires a formulation that can be successfully aerosolised and a delivery system that produces a useful aerosol of the drug; the particles or droplets need to be of sufficient size and mass to be carried to the distal lung or deposited on proximal airways to give rise to a therapeutic effect. Patients and caregivers must use and maintain these aerosol drug delivery devices correctly. In recent years, several technical innovations have led to aerosol drug delivery devices with efficient drug delivery and with novel features that take into account factors such as dose tracking, portability, materials of manufacture, breath actuation, the interface with the patient, combination therapies, and systemic delivery. These changes have improved performance in all four categories of devices: metered dose inhalers, spacers and holding chambers, dry powder inhalers, and nebulisers. Additionally, several therapies usually given by injection are now prescribed as aerosols for use in a range of drug delivery devices. In this Review, we discuss recent developments in the design and clinical use of aerosol devices over the past 10-15 years with an emphasis on the treatment of respiratory disorders.

Pulmonary complications of lung transplantation

Lung transplantation is an effective treatment option for select patients with a variety of end-stage lung diseases. Although transplant can significantly improve the quality of life and prolong survival, a myriad of pulmonary complications may result in significant morbidity and limit long-term survival. The recognition and early treatment of these complications is important for optimizing outcomes. This article provides an overview and update of the pulmonary complications that may be commonly encountered by pulmonologists caring for these patients.

Aerosolized tacrolimus: a case report in a lung transplant recipient

Long-term outcomes after lung transplantation remain poor mainly to the development of bronchiolitis obliterans syndrome (BOS). Currently, treatment options for BOS are very limited. Strategies to prevent and treat this complication include the use of aerosolized therapy with only cyclosporine used in patients to date. We describe the use of aerosolized tacrolimus in a lung transplant recipient with BOS. The patient demonstrated clinical improvement in functional capacity and oxygenation while receiving tacrolimus by nebulization. Further research is needed to study whether aerosolized tacrolimus is beneficial in lung transplant recipients with BOS.

Bronchoalveolar lavage and other methods to define the human respiratory tract milieu in health and disease

During fiber-optic bronchoscopy (FOB), surface sampling of the human respiratory airways and alveolar unit can be done with bronchoalveolar lavage (BAL), plus selective sites can be brushed for cells and transbronchial biopsies made in adjacent tissue. This permits analysis of the respiratory tract's milieu in healthy normals, in those with disease, and in control subjects. These combined procedures have been an established approach for obtaining specimens for research and for clinical assessment for over four decades. However, now new less invasive sampling methods are emerging. This review emphasizes BAL and the cellular and noncellular components recovered in fluid that have contributed to improving knowledge of how the respiratory tree's innate immunity can protect, and how airway structures can become deranged and manifest disease. After a discussion of training for FOB and procedural issues, a spectrum of respiratory diseases studied with BAL is presented, including airway illness (asthma and chronic obstructive pulmonary disease), diffuse interstitial lung diseases [idiopathic pulmonary fibrosis, rheumatoid interstitial lung disease (ILD), granulomatous ILDs], lung infections, lung malignancy, and upper and lower tract airway problems. Some recent studies with exhaled breath condensate analyses are given.

Toward managing chronic rejection after lung transplant: the fate and effects of inhaled cyclosporine in a complex environment

The fate and effects of inhaled cyclosporine A (CsA) are considered after deposition on the lung surface. Special emphasis is given to a post-lung transplant environment and to the potential effects of the drug on the various cell types it is expected to encounter. The known stability, metabolism, pharmacokinetics and pharmacodynamics of the drug have been reviewed and discussed in the context of the lung microenvironment. Arguments support the contention that the immuno-inhibitory and anti-inflammatory effects of CsA are not restricted to T-cells. It is likely that pharmacologically effective concentrations of CsA can be sustained in the lungs but due to the complexity of uptake and action, the elucidation of effective posology must ultimately rely on clinical evidence.

Nanocarriers for pulmonary administration of peptides and therapeutic proteins

Peptides and therapeutic proteins have been the target of intense research and development in recent years by the pharmaceutical and biotechnology industry. Preferably, they are administered through the parenteral route, which is associated with reduced patient compliance. Formulations for noninvasive administration of peptides and therapeutic proteins are currently being developed. Among them, inhalation appears as a promising alternative for the administration of such products. Several formulations for pulmonary delivery are in various stages of development. Despite positive results, conventional formulations have some limitations such as reduced bioavailability and side effects. Nanocarriers may be an alternative way to overcome the problems of conventional formulations. Some nanocarrier-based formulations of peptides and therapeutic proteins are currently under development. The results obtained are promising, revealing the usefulness of these systems in the delivery of such drugs.

Preclinical evaluation of tacrolimus colloidal dispersion for inhalation

Substantial improvements in transplant therapy have been made in the past four decades resulting in the acceptance of organ transplantation as a viable treatment for late-stage disease and organ failure. More recently, lung transplantation has gained acceptance; however, high incidence of chronic rejection and opportunistic infections has limited success rates in comparison with other transplant procedures. To achieve more targeted therapy, pulmonary administration of nebulized tacrolimus (TAC) colloidal dispersion once daily for 28 consecutive days in Sprague Dawley (SD) rats has been investigated for safety and systemic elimination. A liquid dispersion of colloidal TAC and lactose (1:1 ratio by weight) was aerosolized using a vibrating mesh nebulizer and administered via a nose-only dosing chamber. Blood chemistry and histological comparisons to saline-dosed animals showed no clinically significant differences in liver and kidney function or lung tissue damage. Maximum blood and lung concentrations sampled 1h after the final dose showed TAC concentrations of 10.1 ± 1.4 ng/mL and 1758.7 ± 80.0 ng/g, respectively. Twenty-four hours after the final dose, systemic TAC concentrations measured 1.0 ± 0.5 ng/mL, which is well below clinically accepted trough concentrations (5-15 ng/mL) for maintenance therapy, and therefore, would not be expected to induce toxic side effects. The propensity for pulmonary retention seen when compared to single dose lung levels may be due to macrophage uptake and the lipophilic nature of TAC. Additionally, three month stability testing of TAC powder for reconstitution showed no changes in amorphous nature or drug potency when stored at ambient conditions. TAC colloidal dispersion proved to be non-toxic when administered by pulmonary inhalation to SD rats over 28 days while providing therapeutic concentrations locally. This delivery strategy may prove safe and effective for the prevention of lung allograft rejection in lung transplant recipients.

Inhaled lidocaine for the treatment of asthma: lack of efficacy in two double-blind, randomized, placebo-controlled clinical studies

BACKGROUND

Asthma with severe or persistent exacerbations is treated with chronic oral corticosteroids (OCS), such as prednisone. Although efficacious, OCS treatment is often associated with side effects; thus, corticosteroid-sparing treatments are needed.

METHODS

We conducted two double-blind, placebo-controlled, clinical studies assessing lidocaine solution for inhalation (LSI; 40 mg twice daily; eFlow(®) nebulizer) to treat asthma. Study 1-Mild/Moderate included 154 patients with mild-moderate asthma [forced expiratory volume in one second (FEV(1)) ≥60% predicted, and ≥12% improvement in FEV(1) (L) after short-acting, inhaled β-agonist; no OCS or inhaled corticosteroids (ICS) in previous month] and evaluated whether FEV(1) improved after 12 weeks of treatment. Study 2-OCS included 114 patients with more severe asthma (FEV(1) 35-85% of predicted values, treatment with OCS for ≥6 months, average daily dose between 5 and 70 mg prednisone or equivalent, stable ≥30 days) and evaluated whether 20 weeks of treatment had a corticosteroid-sparing effect, measured as reduced need for OCS.

RESULTS

LSI did not improve pulmonary function in Study 1-Mild/Moderate, and did not have a corticosteroid-sparing effect in Study 2-OCS, when compared with placebo. Thus, the primary efficacy endpoints were not met. Significant improvements were not observed for asthma symptom scores, morning and evening peak expiratory flow values, FEV(1) % predicted, proportion of patients with asthma instability, and asthma quality-of-life scores at week 12 (Study 1-Mild/Moderate) or week 20 (Study 2-OCS). LSI was well tolerated.

CONCLUSIONS

These results indicate that lidocaine solution for inhalation is not a useful treatment for asthma; it did not improve pulmonary function and did not have a corticosteroid-sparing effect.

Extracorporeal photopheresis in patients with refractory bronchiolitis obliterans developing after allo-SCT

Extracorporeal photopheresis (ECP) has been shown to be a promising treatment for chronic graft-versus-host disease; however, only a few case reports are available that examine the effectiveness of ECP for bronchiolitis obliterans (BO) after allo-SCT. Because of the poor response to traditional therapies, ECP has been explored as a possible therapeutic option for severe BO after allo-SCT. Nine patients received ECP between July 2008 and August 2009 after a median follow-up of 23 months (range 9-93 months) post transplant. The primary indication for ECP was the development of BO in patients who had failed prior multidrug regimens. The median number of drugs used for BO management before ECP was 5 (range 2-7); this included immunosuppressive therapy. Six of nine (67%) patients responded to ECP after a median of 25 days (range 20-958 days). No ECP-related complications occurred. ECP seemed to stabilize rapidly declining pulmonary function tests in about two-thirds of patients with severe and heavily pretreated BO that developed after allo-SCT. This finding supports the need for a larger prospective study to confirm the impact of ECP on BO, and to consider earlier intervention with ECP to improve the outcome of BO after allo-SCT.

Inhaled cyclosporine and pulmonary function in lung transplant recipients

BACKGROUND

Chronic rejection, manifesting as bronchiolitis obliterans, is the leading cause of death in lung transplant recipients. In our previously reported double-blinded, placebo-controlled trial comparing inhaled cyclosporine (ACsA) to aerosol placebo, the rate of bronchiolitis-free survival improved. However, an independent analysis of pulmonary function, a secondary endpoint of the trial, was not performed. We sought to determine the effect of ACsA, in addition to systemic immunosuppression, on pulmonary function.

METHODS

From 1998-2001, 58 patients were randomly assigned to inhale either 300 mg of ACsA (28 patients) or placebo aerosol (30 patients) 3 days a week for the first 2 years after transplantation. Longitudinal changes in pulmonary function of ACsA patients were compared to aerosol placebo patients. In another analysis, the rate of decline from 6-month maximum FEV(1) in randomized patients was compared to the rate of decline in patients receiving conventional immunosuppression from the Novartis transplant database (644 patients, 12 centers worldwide, transplanted from 1990-1995).

RESULTS

The average duration of ACsA and aerosol placebo was 400 days +/- 306 and 433 +/- 256, respectively. The change in FEV(1) of ACsA patients (adjusted for Cytomegalovirus (CMV) mismatch and transplant type, followed for a maximum duration of 4.6 years) was superior to the aerosol placebo controls (9.0 +/- 71.4 mL/year vs. -107.9 +/- 55.3, p = 0.007). The FEF(25-75) decreased by -220.3 +/- 117.7 L/(second x year) vs. -412.2 +/- 139.2, p = 0.07, respectively. Similarly, percent FEV(1) decline from maximal values was improved in ACsA patients compared to aerosol placebo and Novartis controls (ACsA -0.43 +/- 1.12%/year vs. aerosol placebo -4.08 +/- 1.4, p = 0.04; ACsA vs. Novartis -4.7 +/- 0.31, p = 0.007). Single-lung recipients receiving ACsA showed improvement in FEV(1) compared to Novartis controls (FEV(1) -0.8 +/- 1.8%/year vs. -4.94 +/- 0.4, p = 0.03) but double-lung recipients showed improvement compared to aerosol placebo controls only (FEV(1) -0.28 +/- 1.22%/year vs. -8.53 +/- 5.95, p = 0.048).

CONCLUSIONS

In this single center trial, ACsA appears to ameliorate important pulmonary function parameters in lung transplant recipients compared to aerosol placebo and historical control patients. Single- and double-lung transplant recipients may not respond uniformly to treatment, and ongoing randomized trials in lung transplant recipients using ACsA may help elucidate our findings.

Pediatric lung transplantation

Lung transplantation is an accepted therapy for selected pediatric patients with severe end-stage vascular or parenchymal lung disease. Collaboration between the patients' primary care physicians, the lung transplant team, patients, and patients' families is essential. The challenges of this treatment include the limited availability of suitable donor organs, the toxicity of immunosuppressive medications needed to prevent rejection, the prevention and treatment of obliterative bronchiolitis, and maximizing growth, development, and quality of life of the recipients. This article describes the current status of pediatric lung transplantation, indications for listing, evaluation of recipient and donor, updates on the operative procedure,graft dysfunction, and the risk factors, outcomes, and future directions.

Update on paediatric lung transplantation

Lung transplantation is well-established in the treatment of end-stage lung disease in children. Our understanding of the problems associated with transplantation has increased rapidly over the past 25 years. Recent figures suggest this knowledge is starting to translate into improvements in management and survival. The common indications for lung transplantation in children, the process of assessment and the outcomes and complications of transplantation are reviewed. We discuss briefly some of the ethical issues relevant to lung transplantation and review strategies for the future. This information may help the respiratory paediatrician prepare potential candidates and their families for the process of assessment and help him or her anticipate common problems that may occur.

Evaluation of metered dose inhaler (MDI) formulations of ciclosporin

Our purpose was to evaluate metered dose inhaler (MDI) formulations of ciclosporin (cyclosporine) for aerodynamic properties, chemical stability and bioactivity. Ciclosporin formulations (0.1, 0.5 and 1.0% w/w) were prepared in hydrofluoroalkane (HFA) propellants (134a and 227) containing 3 and 6% ethanol. Aerodynamic properties of the MDI formulations were analysed using an eight-stage Andersen cascade impactor and respirable mass and non-respirable mass, mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) were determined from the impaction profiles. The chemical stability of 0.1% ciclosporin in HFA 227 containing 3% ethanol formulation stored at room temperature and 40°C was evaluated by HPLC at 0, 14, 30 and 90 days. The bioactivity of ciclosporin MDI formulations was evaluated by determining the ciclosporin-mediated inhibition of interleukin-2 (IL-2) release from human Jurkat cells stimulated with phorbol 12-myristate 13-acetate (PMA). As ethanol concentration increased from 3 to 6%, respirable mass decreased from 2.3 mg per five actuations to 0.04 mg per five actuations for HFA 227 formulations, and from 1.5 mg to 0.09 mg per five actuations for HFA 134a formulations. The MMAD for both HFA 134a and 227 formulations increased with an increase in ciclosporin concentration. HPLC analysis showed ciclosporin to be extremely stable in HFA 227 at room temperature and 40°C. Stimulation of Jurkat cells with PMA released significant amounts of IL-2, which was inhibited by ciclosporin in a dose-dependent manner. This study shows the feasibility of developing chemically stable and bioactive HFA-based MDI formulations of ciclosporin.

[Early postoperative management and immunosuppressive treatment following lung transplantation]

Lung transplantation is now considered a valid option in the management of end-stage respiratory failure. The postoperative period remains a key stage that will influence the average long-term prognosis of the patients. Primary graft failure, postoperative bleeding, infection, acute rejection and complications linked to the surgery, and to vascular or bronchial anastomoses, are risk factors for mortality and morbidity. These must be taken care of quickly via collaboration with the surgical team. The immunosuppressive treatment essential for tolerance induction with regard to the transplanted organ will be introduced during the intraoperative period and continued for life. The combination of a calcineurin inhibitor, an antiproliferative agent and corticosteroids remains the conventional procedure. The role of new molecules as mTor inhibitors remains to be determined.

[Medical complications of lung transplantation]

In 2010, lung transplantation is a valuable therapeutic option for a number of patients suffering from of end-stage non-neoplastic pulmonary diseases. The patients frequently regain a very good quality of life, however, long-term survival is often hampered by the development of complications such as the bronchiolitis obliterans syndrome, metabolic and infectious complications. As the bronchiolitis obliterans syndrome is the first cause of death in the medium and long term, an intense immunosuppressive treatment is maintained for life in order to prevent or stabilize this complication. The immunosuppression on the other hand induces a number of potentially severe complications including metabolic complications, infections and malignancies. The most frequent metabolic complications are arterial hypertension, chronic renal insufficiency, diabetes, hyperlipidemia and osteoporosis. Bacterial, viral and fungal infections are the second cause of mortality. They are to be considered as medical emergencies and require urgent assessment and targeted therapy after microbiologic specimens have been obtained. They should not, under any circumstances, be treated empirically and it has also to be kept in mind that the lung transplant recipient may present several concomitant infections. The most frequent malignancies are skin cancers, the post-transplant lymphoproliferative disorders, Kaposi's sarcoma and some types of bronchogenic carcinomas, head/neck and digestive cancers. Lung transplantation is no longer an exceptional procedure; thus, the pulmonologist will be confronted with such patients and should be able to recognize the symptoms and signs of the principal non-surgical complications. The goal of this review is to give a general overview of the most frequently encountered complications. Their assessment and treatment, though, will most often require the input of other specialists and a multidisciplinary and transversal approach.

Mechanisms behind local immunosuppression using inhaled tacrolimus in preclinical models of lung transplantation

Inhaled immunosuppression with tacrolimus (TAC) is a novel strategy after lung transplantation. Here we investigate the feasibility of tacrolimus delivery via aerosol, assess its immunosuppressive efficacy, reveal possible mechanisms of action, and evaluate its airway toxicity. Rats received 4 mg/kg TAC via oral or inhaled (AER) administration. Pharmacokinetic properties were compared, and in vivo airway toxicity was assessed. Full-thickness human airway epithelium (AE) was grown in vitro at an air-liquid interface. Equal TAC doses (10-1,000 ng) were either added to the bottom chamber (MED) or aerosolized for gas-phase exposure (AER). Airway epithelium TAC absorption, cell toxicity, and interactions of TAC with NFκB activation were studied. Single-photon emission computed tomography demonstrated a linear tracer accumulation within the lungs during TAC inhalation. The AER TAC generated higher lung-tissue concentrations, but blood concentrations that were 11 times lower. Airway histology and gene expression did not reveal drug toxicity after 3 weeks of treatment. In vitro AE exposed to TAC at 10-1,000 ng, orally or AER, maintained its pseudostratified morphology, did not show cell toxicity, and maintained its epithelial integrity, with tight junction formation. The TAC AER-treated AE absorbed the drug from the apical surface and generated lower-chamber TAC concentrations sufficient to suppress activated lymphocytes. Tacrolimus AER was superior to TAC MED at preventing AE IFN-γ, IL-10, IL-13, monocyte chemoattractant protein-1 chemokine (C-C motif) ligand 5 (RANTES) and TNF-α up-regulation. Tacrolimus inhibited airway epithelial cell NFκB activation. In conclusion, TAC can be delivered easily and effectively into the lungs without causing airway toxicity, decreases inflammatory AE cytokine production, and inhibits NFκB activation.

Delivery of antibiotics to the respiratory tract: an update

The use of inhaled medications for the treatment of pulmonary diseases has become an increasingly popular drug delivery route over the past few decades. This delivery route allows for a drug to be delivered directly to the site of the disease, with a lower dose than more conventional oral or intravenous delivery methods, with reduced systemic absorption and consequently reduced risk of adverse effects. For asthma this delivery route has become the 'golden standard' of therapy. It is not unexpected therefore, that there has been great interest in the prospect of using inhaled antibiotics for the treatment of both chronic and recurrent respiratory infections. Since the early 1980s, several investigations have demonstrated that antibiotics could be delivered safely by means of inhalation, using nebulisers as their delivery systems. Lately, antibiotics delivery via inhalation have seen a 'revival' in interest and most of these studies have focused on delivering antibiotics to the lungs by means of a dry powder format. This review focuses on recent advances in antibiotic inhalation therapy.

Using regression models to analyze randomized trials: asymptotically valid hypothesis tests despite incorrectly specified models

Regression models are often used to test for cause-effect relationships from data collected in randomized trials or experiments. This practice has deservedly come under heavy scrutiny, because commonly used models such as linear and logistic regression will often not capture the actual relationships between variables, and incorrectly specified models potentially lead to incorrect conclusions. In this article, we focus on hypothesis tests of whether the treatment given in a randomized trial has any effect on the mean of the primary outcome, within strata of baseline variables such as age, sex, and health status. Our primary concern is ensuring that such hypothesis tests have correct type I error for large samples. Our main result is that for a surprisingly large class of commonly used regression models, standard regression-based hypothesis tests (but using robust variance estimators) are guaranteed to have correct type I error for large samples, even when the models are incorrectly specified. To the best of our knowledge, this robustness of such model-based hypothesis tests to incorrectly specified models was previously unknown for Poisson regression models and for other commonly used models we consider. Our results have practical implications for understanding the reliability of commonly used, model-based tests for analyzing randomized trials.

Lung deposition of a liposomal cyclosporine A inhalation solution in patients after lung transplantation

BACKGROUND

Bronchiolitis obliterans is the most important long-term sequelae of lung transplantation limiting survival. Optimized immunosuppression, including inhalation of cyclosporine A (CsA), may be a promising approach to overcome this problem.

METHODS

In this study a liposomal CsA solution was characterized in vitro, doses of 10 and 20 mg were inhaled with the PARI eFlow inhaler by 12 stable lung transplant recipients, and lung deposition was evaluated by gamma scintigraphy.

RESULTS

Inhalation of CsA leads to lung deposition of 40 +/- 6% (10 mg) and 33 +/- 7% (20 mg), respectively. This deposition resulted in a peripheral lung dose of 2.0 +/- 0.4 mg (10 mg) and 3.4 +/- 0.8 mg (20 mg), respectively. Extrathoracic deposition was 16 +/- 6% (10 mg) and 14 +/- 4% (20 mg), respectively, and the total deposition was calculated with 56% (10 mg) and 46% (20 mg). Lung deposition and peripheral lung deposition increased significantly with treatment time. The maximum CsA blood concentration and the area under the time course of blood concentration correlated with peripheral lung deposition. There were no statistically significant differences between patients with single- and double-lung transplantation. Inhalation of the study medication was well tolerated, and led to only minor but statistically significant changes in lung function parameters (FEV(1): -0.07 L; FVC: -0.09 L; sRaw: +0.35 kPa s.).

CONCLUSIONS

The new liposomal CsA PARI formulation can be deposited to the peripheral lung using the PARI eFlow nebulizer. The treatment was well tolerated, and no drug-related side effects were observed. Once or twice daily dosing of 10 mg CsA A PARI would result in a sufficient peripheral lung deposition of approximately 14 and 28 mg/week, respectively.

Aerosol drug delivery in lung transplant recipients

BACKGROUND

Inhaled drug delivery after lung transplantation provides a unique opportunity for direct treatment of a solid organ transplant. At present, no inhaled therapies are approved for this population though several have received some development. Primary potential applications include inhaled immunosuppressive and anti-infective drugs.

OBJECTIVES

The objective of this article is to review potential applications of inhaled medications for lung transplant recipients, the techniques used to develop inhaled drugs and the challenges of aerosol delivery in this specific population.

METHODS

The results of relevant studies are reviewed and two developmental examples are presented.

RESULTS/CONCLUSIONS

Inhaled medications may provide significant advantages for lung transplant recipients. Past studies with inhaled cyclosporine and amphotericin-B provide useful guidance for clinical development of new preparations.