In the upcoming years, the proportion of elderly patients with chronic obstructive pulmonary disease (COPD) will increase, according to the progressively aging population and the increased efficacy of the pharmacological treatments, especially considering the management of chronic comorbidities. The issue to prescribe an appropriate inhalation therapy to COPD patients with significant handling or coordination difficulties represents a common clinical experience; in the latter case, the choice of an inadequate inhalation device may jeopardize the adherence to the treatment and eventually lead to its ineffectiveness. Treatment options that do not require particular timing for coordination between activation and/or inhalation or require high flow thresholds to be activated should represent the best treatment option for these patients. Nebulized bronchodilators, usually used only in acute conditions such as COPD exacerbations, could fulfill this gap, enabling an adequate drug administration during tidal breathing and without the need for patients' cooperation. However, so far, only short-acting muscarinic antagonists have been available for nebulization. Recently, a nebulized formulation of the inhaled long-acting muscarinic antagonist glycopyrrolate, delivered by means of a novel proprietary vibrating mesh nebulizer closed system (SUN-101/eFlow®), has progressed to Phase III trials and is currently in late-stage development as an option for maintenance treatment in COPD. The present critical review describes the current knowledge about the novel nebulizer technology, the efficacy, safety, and critical role of nebulized glycopyrrolate in patients with COPD. To this end, PubMed, ClinicalTrials.gov, Embase, and Cochrane Library have been searched for relevant papers. According to the available results, the efficacy and tolerability profile of nebulized glycopyrrolate may represent a valuable and dynamic treatment option for the chronic pharmacological management of patients with COPD.
Keywords: COPD; antimuscarinic; device; glycopyrrolate; glycopyrronium; nebulizer.