Synergy across the drugs approved for the treatment of asthma.

INTRODUCTION: Inhaled corticosteroids are the cornerstone for the treatment of stable asthma, however, when disease severity increases, escalating therapy to combinations of drugs acting on distinct signalling pathways is required. It is advantageous to providing evidence of a synergistic interaction across drug combinations, as it allows optimizing bronchodilation while lowering the dose of single agents. In the respiratory pharmacology field, two statistical models are accepted as gold standard to characterize drug interactions, namely the Bliss Independence criterion and the Unified Theory. In this review, pharmacological interactions across drugs approved for the treatment of asthma have been systematically assessed. EVIDENCE ACQUISITION: A comprehensive literature search was performed in MEDLINE for studies that used a validated pharmacological method for assessing drug interaction. The results were extracted and reported via qualitative synthesis. EVIDENCE SYNTHESIS: Overall, 45 studies were identified from literature search and 5 met the inclusion criteria. Current evidence coming from ex-vivo models of asthma indicates that drug combinations modulating bronchial contractility induce a synergistic bronchorelaxant effect. In murine models of lung inflammation, the combination between inhaled corticosteroids and ß2-adrenoceptor agonists synergistically improve lung function and the inflammatory profile. CONCLUSIONS: There is still limited knowledge regarding the mechanistic basis underlying pharmacological interactions across drugs approved for asthma. The synergism elicited by combined agents is an effect of class. Specifically designed clinical trials are needed to confirm the results coming from preclinical evidence, but also to establish the minimal dose for combined agents to induce a synergistic interaction and maximize bronchodilation.

Experimental Glucocorticoid Receptor Agonists for the Treatment of Asthma: A Systematic Review.

Inhaled corticosteroids (ICSs) are considered the cornerstone of asthma treatment. Despite the solid evidence documenting the efficacy and safety of ICSs at the level of the airways, their use can be affected by pulmonary and systemic adverse events (AEs) when administered chronically and/or at high doses. Thus, there is a pharmacological and medical need for new glucocorticoid (GC) receptor (GR) ligands with a more favorable therapeutic index, in order to overcome the shortcomings of currently available ICSs. The therapeutic profile of GCs can be improved by enhancing genomic mechanisms mediated by transrepression, which is assumed to be responsible for several anti-inflammatory and immunomodulatory actions, rather than transactivation, which causes most of the GC-associated AEs. It was assumed that an independent modulation of the molecular mechanisms underlying transactivation and transrepression could translate into the dissociation of beneficial effects from AEs. Therefore, current research is looking for GCs that are able to elicit prevalently transrepression with negligible transactivating activity. These compounds are known as selective glucocorticoid receptor agonists (SEGRAs). In this review, experimental GR agonists currently in pre-clinical and clinical development for the treatment of asthma have been systematically assessed. Several compounds are currently under pre-clinical development, but only three novel experimental GR agonists (GW870086X, AZD5423, AZD7594) seem to have some potential therapeutic relevance and have entered clinical trials for the treatment of asthma. Since data from pre-clinical studies have not always been confirmed in clinical investigations, well-designed randomized controlled trials are needed in asthmatic patients to confirm the potentially positive benefit/risk ratio of each specific SEGRA and to optimize the development strategy of these agents in respiratory medicine.

Diagnostic Performance and Safety of Bronchoalveolar Lavage in Thrombocytopenic Haematological Patients for Invasive Fungal Infections Diagnosis: A Monocentric, Retrospective Experience.

BACKGROUND: Although bronchoalveolar lavage (BAL) measurements of galactomannan antigen (GM) seems to be more sensitive than serum testing to detect invasive fungal infection (IFI), a consensus on the most appropriate diagnostic threshold of the BAL GM test is still unclear. Moreover, there is uncertainty as to whether BAL is a safe procedure in patients with hematological malignancies (HM) and thrombocytopenia. OBJECTIVES: Based on this background, 102 adult patients with HM and associated thrombocytopenia were retrospectively analyzed with the dual aim of 1) determining whether BAL is a safe and feasible procedure; and, 2) identifying the most appropriate threshold for GM positivity in the diagnosis of IFI. PATIENTS/METHODS: each BAL was considered as one case/patient. One hundred twelve BALs were carried out in 102 HM patients: at the time of the BAL, the median platelet count (PLTs) in all patients was 47×109/L (1-476), and 31 patients (27%) had PLTs< 20×109/L. RESULTS: complications from the BAL were infrequent (3.5%) and mild. No bleeding was reported. The BAL GM cut off of >0.8 was associated with the best diagnostic accuracy (sensitivity 72.97% and specificity 80%). Antifungal treatment of patients with BAL GM >0.8 resulted in a clinical-radiological improvement in 35/41 patients (85%). CONCLUSIONS: BAL was a safe procedure also in thrombocytopenic patients, permitting an IFI diagnosis not otherwise identifiable using EORTC/MSG criteria. Our data suggest that a BAL GM value of>0.8 represents the most useful cut-off in terms of sensibility and specificity. Further prospective studies on a more significant number of patients are needed to confirm these results.