Olodaterol is a beta2-adrenoceptor agonist discovered by Boehringer Ingelheim and approved for the treatment of Chronic Obstructive Pulmonary Disease. The compound exerts its pharmacological effects by binding and activation of beta2-adrenoceptors after inhalation. Activation of these receptors in the airways results in a stimulation of intracellular adenyl cyclase, an enzyme that mediates the synthesis of cyclic-3’, 5’ adenosine monophosphate (cAMP). Elevated levels of cAMP induce bronchodilation by relaxation of airway smooth muscle cells. Olodaterol effect lasts for 24 hours.

Vilanterol (INN, USAN) is an ultra-long-acting β2 adrenoreceptor agonist (ultra-LABA), which was approved in May 2013 in combination with fluticasone furoate for sale as Breo Ellipta by GlaxoSmithKline for the treatment of chronic obstructive pulmonary disease (COPD). Its pharmacological effect is attributable to stimulation of intracellular adenylyl cyclase which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic-3’,5’-adenosine monophosphate (cAMP). Increases in cyclic AMP are associated with relaxation of bronchial smooth muscle and inhibition of release of hypersensitivity mediators from mast cells in the lungs. Vilanterol is available in following combinations: a) with inhaled corticosteroid fluticasone furoate — fluticasone furoate/vilanterol (trade names Breo Ellipta , Relvar Ellipta; b) with muscarinic antagonist umeclidinium bromide — umeclidinium bromide/vilanterol (trade name Anoro Ellipta).

Umeclidinium (used as a bromide salt) is a long-acting, antimuscarinic antagonist, often referred to as an anticholinergic, developed for the treatment of chronic obstructive pulmonary disease (COPD) (alone and in combination with Vilanterol - long-acting beta2-adrenergic agonist). Umeclidinium has similar affinity to the subtypes of muscarinic receptors M1 to M5 with Ki values of 0.16 nM, 0.15 nM, 0.06 nM, 0.05 nM and 0.13 nM for M1, M2, M3, M4 and M5, respectively. Umeclidinium is selective against mAChR over other unrelated receptors or channels such as κ and σ opiod receptors, Na+ channel and dopamine transporter. In the airways, it exhibits pharmacological effects through the inhibition of M3 receptor at the smooth muscle leading to bronchodilation. There is potential for an additive interaction with concomitantly used anticholinergic medicines.

Aclidinium is a long-acting, competitive, and reversible anticholinergic drug that is specific for the acetylcholine muscarinic receptors. It binds to all 5 muscarinic receptor subtypes to a similar affinity. It has a much higher propensity to bind to muscarinic receptors than nicotinic receptors. FDA approved on July 24, 2012. Aclidinium's effects on the airways are mediated through the M3 receptor at the smooth muscle to cause bronchodilation. Prevention of acetylcholine-induced bronchoconstriction effects was dose-dependent and lasted longer than 24 hours.

Roflumilast is a specific phosphodiesterase type (4PDE4) inhibitor indicated for use as a treatment to reduce the risk of COPD exacerbations in patients with severe COPD associated with chronic bronchitis and a history of exacerbations.

Fluticasone furoate is a synthetic trifluorinated corticosteroid with potent anti-inflammatory activity. Fluticasone furoate is a anti-allergic agents that is FDA approved for the treatment of symptoms of seasonal and perennial allergic rhinitis, asthma and for reducing exacerbations in patients with chronic obstructive pulmonary disease. Fluticasone furoate has been shown in vitro to exhibit a binding affinity for the human glucocorticoid receptor. The clinical relevance of these findings is unknown. The most common adverse reactions (>1% incidence) included headache, epistaxis, pharyngolaryngeal pain, nasal ulceration, back pain, pyrexia, and cough. Coadministration of ritonavir is not recommended. Use caution with coadministration of other potent CYP3A4 inhibitors, such as ketoconazole.

Ciclesonide is a glucocorticoid receptor agonist indicated for the treatment of allergic rhinitis (Omnaris nasal spray) and asthma (Alvesco). It was also developed by Byk Gulden for chronic obstructive pulmonary disease (COPD), but no development had been reported for this indication since 1999. Ciclesonide is a pro-drug and rapidly metabolized to C21-desisobutyryl-ciclesonide which is more potent toward GR receptor than the parent drug.

Tiotropium is a long–acting, antimuscarinic agent, which is often referred to as an anticholinergic. It has similar affinity to the subtypes of muscarinic receptors, M1 to M5. In the airways, it exhibits pharmacological effects through inhibition of M3–receptors at the smooth muscle leading to bronchodilation. The competitive and reversible nature of antagonism was shown with human and animal origin receptors and isolated organ preparations. In preclinical in vitro as well as in vivo studies prevention of methacholine–induced bronchoconstriction effects were dose–dependent and lasted longer than 24 hours. The bronchodilation following inhalation of tiotropium is predominantly a site–specific effect. Tiotropium is a muscarinic receptor antagonist, often referred to as an antimuscarinic or anticholinergic agent. Although it does not display selectivity for specific muscarinic receptors, on topical application it acts mainly on M3 muscarinic receptors located in the airways to produce smooth muscle relaxation, thus producing a bronchodilatory effect. Tiotropium is used in the management of chronic obstructive pulmonary disease (COPD).Tiotropium bromide capsules for inhalation are co-promoted by Boehringer-Ingelheim and Pfizer under the trade name Spiriva. It is also manufactured and marketed by Cipla under trade name Tiova.

Formoterol is a long-acting selective beta2-adrenergic receptor agonist (beta2-agonist). Inhaled formoterol fumarate acts locally in the lung as a bronchodilator. In vitro studies have shown that formoterol has more than 200-fold greater agonist activity at beta2-receptors than at beta1- receptors. Although beta2-receptors are the predominant adrenergic receptors in bronchial smooth muscle and beta1-receptors are the predominant receptors in the heart, there are also beta2-receptors in the human heart comprising 10%-50% of the total beta-adrenergic receptors. The precise function of these receptors has not been established, but they raise the possibility that even highly selective beta2- agonists may have cardiac effects. The pharmacologic effects of beta2-adrenoceptor agonist drugs, including formoterol, are at least in part attributable to stimulation of intracellular adenyl cyclase, the enzyme that catalyzes the conversion of adenosine triphosphate (ATP) to cyclic-3', 5'-adenosine monophosphate (cyclic AMP). Increased cyclic AMP levels cause relaxation of bronchial smooth muscle and inhibits the release of pro-inflammatory mast-cell mediators such as histamine and leukotrienes. Formoterol also inhibits histamine-induced plasma albumin extravasation in anesthetized guinea pigs and inhibits allergen-induced eosinophil influx in dogs with airway hyper-responsiveness. The relevance of these in vitro and animal findings to humans is unknown. Formoterol is used for use as long-term maintenance treatment of asthma in patients 6 years of age and older with reversible obstructive airways disease, including patients with symptoms of nocturnal asthma, who are using optimal corticosteroid treatment and experiencing regular or frequent breakthrough symptoms requiring use of a short-acting bronchodilator. Not indicated for asthma that can be successfully managed with occasional use of an inhaled, short-acting beta2-adrenergic agonist. Also used for the prevention of exercise-induced bronchospasm, as well as long-term treatment of bronchospasm associated with COPD. Marketed as Foradil Aerolizer.

Montelukast (SINGULAIR®) is a selective and orally active leukotriene D4 (LTD4) receptor antagonist that inhibits the cysteinyl leukotriene CysLT1 receptor. It is indicated for the prophylaxis and chronic treatment of asthma, for prevention of exercise-induced bronchoconstriction, and for the relief of symptoms of seasonal allergic rhinitis. LTD4 is a product of arachidonic acid metabolism and is released from various cells, including mast cells and eosinophils. This eicosanoid binds to CysLT1 receptor found in the human airway (including airway smooth muscle cells and airway macrophages) and on other pro-inflammatory cells (including eosinophils and certain myeloid stem cells). Cysteinyl leukotriene receptors (CysLTs) have been correlated with the pathophysiology of asthma and allergic rhinitis. In asthma, leukotriene-mediated effects include airway edema, smooth muscle contraction, and altered cellular activity associated with the inflammatory process. In allergic rhinitis, CysLTs are released from the nasal mucosa after allergen exposure during both earlyand late-phase reactions and are associated with symptoms of allergic rhinitis. Montelukast (SINGULAIR®) binds with high affinity and selectivity to the CysLT1 (in preference to other pharmacologically important airway receptors, such as the prostanoid, cholinergic, or beta-adrenergic receptor). It inhibits physiologic actions of LTD4 at the CysLT1 receptor without any agonist activity.