PURPOSE: To evaluate the relationship between the IOP-lowering effect of trabodenoson and the associated structural and functional changes in the trabecular meshwork (TM). METHODS: Six independent cohorts of young and aged mice were exposed to three different topical once-a-day formulations of trabodenoson and eyes were compared to those treated with placebo drops. IOP was measured daily just before drug administration using rebound tonometry. Outflow facility was measured in enucleated eyes. Flow patterns and morphology of conventional outflow tissues were monitored using tracer beads and standard histology, respectively. In parallel, three-dimensional human TM tissue constructs (3D-HTM) were grown and used in experiments to test effect of trabodenoson on the expression of collagen IV, fibronectin, matrix metalloproteinase (MMP)-2 and MMP-14 plus MMP-2 activity. RESULTS: Topical administration of trabodenoson significantly lowered IOP on every day tested, up to 7 days. After 2 days of treatment, outflow facility increased by 26% in aged mice and 30% overall (young and aged mice), which was significantly different from vehicle (P < 0.05). Outflow facility was 15% higher than controls after 7 days of treatment (P = 0.07). While gross morphology was not affected by treatment, the intensity of tracer bead distribution increased by day 7 (P = 0.05). Parallel experiments in 3D-HTM showed that trabodenoson treatment significantly increased MMP-2 activity and MMP-14 abundance, while decreasing fibronectin and collagen IV expression. CONCLUSIONS: Trabodenoson alters ECM turnover by TM cells and increases conventional outflow facility, which accounts for its ability to lower IOP in young and aged mice.

Purpose:To determine the efficacy of trabodenoson, an adenosine mimetic with highly selective adenosine A1 receptor binding properties, in a preclinical mouse model for dry-eye disease.Methods:Dry-eye disease was induced in adult male C57BL/6 mice using a combination of desiccating environment and transdermal administration of scopolamine. Mice were treated concurrently and twice daily with either vehicle, 6% trabodenoson, or 0.05% cyclosporine (Restasis). Efficacy (P < 0.05 versus vehicle) was determined by clinical assessment of dry-eye symptoms using corneal fluorescein staining and tear volumes and histopathologically by quantifying lacrimal gland pathology and conjunctival goblet cells.Results:Twice-daily topical (ocular) administration of trabodenoson increased tear levels and reduced corneal fluorescein staining (P < 0.05) as compared with vehicle-treated eyes in a mouse model of dry-eye disease. Furthermore, significant infiltration of immune cells in the lacrimal gland and reduced number of mucin-producing conjunctival goblet cells were noted in both untreated and vehicle-treated eyes. Comparatively, trabodenoson treatment significantly reduced lacrimal gland infiltration and increased the number of goblet cells (P < 0.05 for both versus vehicle). These trabodenoson-related effects on lacrimal gland pathology and goblet cells were similar to or better than the effects observed with cyclosporine treatment.Conclusions:Topical ocular delivery of trabodenoson significantly improves the clinical and histopathological signs associated with dry-eye disease in mice. This improvement appears to be related to anti-inflammatory effects from targeting adenosine signaling and represents a novel therapeutic approach to develop for the management of dry-eye disease.

Purpose: Nonarteritic anterior ischemic optic neuropathy (NAION) is the leading cause of sudden optic nerve–related vision loss currently without effective treatment. We evaluated the neuroprotective potential of ocular (topical) delivery of trabodenoson, a selective A1 receptor mimetic, in a rodent model of NAION (rNAION). Methods: Daily topical delivery of 3% trabodenoson or vehicle administered in both eyes 3 days prior to rNAION induction and for 21 days post induction. Retinal appearance and optic nerve head (ONH) edema was evaluated using spectral-domain optical coherence tomography (SD-OCT). Retinal function was evaluated before and after induction by ganzfeld electroretinography (ERG). Brn3a(+) retinal ganglion cells (RGCs) were quantified by stereology. Axonal ultrastructure was evaluated by electron microscopy. Results: Trabodenoson-treated eyes had significantly reduced optic nerve (ON) edema compared with vehicle-treated eyes (ANOVA, P < 0.05). Electrophysiologically, there was a nonsignificant trend toward b-wave and oscillatory potential (OP) preservation in the trabodenoson-treated eyes. RGC counts were higher in trabodenoson-treated eyes compared to vehicle (74% versus 47% of the contralateral eye; two-tailed t-test; P = 0.01), as were ON axons. No overt morphologic differences in cell inflammation were observed between vehicle- and trabodenoson-treated ONHs, but trabodenoson-treated ONHs revealed increased expression of astrocyte-related neuroprotective responses. Conclusions: Trabodenoson preserves RGCs in the rodent NAION model. While previous clinical trials focused on trabodenoson's ocular antihypertensive effect, our data suggest trabodenoson's primary target may be both the retina and ONH. Selective adenosine A1 agonists may prove an appropriate neuroprotective adjunctive for ischemia-related ON diseases such as NAION and glaucoma. Translational Relevance: RGC and ON neuroprotection in ischemic neuropathies may be achievable by topical administration of A1 adenosine agonists rather than by simply relying on intraocular pressure reduction.

Purpose: To evaluate the safety and ocular hypotensive efficacy of 4 trabodenoson doses administered twice daily over 14 or 28 days in subjects with ocular hypertension or primary open-angle glaucoma (POAG). Methods: In this multicenter, randomized, double-masked, placebo-controlled, dose-escalation Phase 2 study, patients received unilateral topical twice-daily trabodenoson (50, 100, or 200mcg) or placebo for 14 days, or 500mcg trabodenoson or placebo for 28 days. Ocular and systemic safety and tolerability were assessed by examinations, clinical and laboratory studies. Intraocular pressure (IOP) was assessed using Goldmann tonometry. Results: Trabodenoson was well tolerated; no clinically meaningful ocular or systemic side effects were identified. Trabodenoson produced a dose-dependent IOP reduction. IOP reductions in the 500mcg group were significantly greater than placebo at all time points at Day 28. Mean IOP reductions from diurnal baseline ranged from -3.5 to -5.0mmHg with a mean change of -4.1mmHg in the 500mcg group compared -1.0 to -2.5mmHg with a mean change of -1.6mmHg for the placebo group, and the Day 28 drop was significantly greater than at Day 14 (P=0.0163) indicating improvement in IOP lowering with longer treatment time. IOP remained significantly reduced 24h after the final 500mcg dose (P=0.048). Conclusion: Twice-daily ocular doses of trabodenoson, from 50 to 500mcg, were well tolerated and showed a dose-related decrease in IOP that was statistically significant and clinically relevant at 500mcg in patients with ocular hypertension or POAG.

Purpose: To investigate the safety, tolerability, and pharmacokinetics of trabodenoson, a highly selective adenosine mimetic targeting the adenosine A(1) receptor. Methods: In Part 1, 60 healthy adult volunteers were randomized to 14 days of twice-daily topical monocular application of placebo or trabodenoson (200, 400, 800, 1,600, 2,400, or 3,200g). In Part 2, 10 subjects were randomized to placebo or 8 escalating doses of bilateral trabodenoson (total daily doses: 1,800-6,400g). Results: The incidence of treatment-related adverse events in Part 1 was similar in the trabodenoson (27.8%) and placebo (25.0%) groups. Most were mild in intensity. The most common adverse events (AEs) for trabodenoson and placebo were headache (25.0% vs. 33%, respectively) and eye pain (11.1% vs. 4.2%, respectively). Ocular AEs were infrequent (16.7% and 17.9%, respectively), were self-limited, lasted <24h, and were typically mild in intensity. The most common ocular AE was eye pain (9.5% and 3.6%, respectively), with a single observation of ocular hyperemia (200g trabodenoson). Trabodenoson was rapidly absorbed [median time to maximum concentration (t(max)): approximate to 0.08 to 0.27h] and eliminated (t(1/2): 0.48-2.0h), with no evidence of drug accumulation. Systemic exposure to topical trabodenoson was dose related but not dose proportional, with a plateau effect at doses 2,400mg per eye. No clinically significant treatment-related systemic AEs were observed, and increasing systemic exposure had no effect on heart rate or blood pressure. Conclusions: Ocular doses of trabodenoson up to 3,200g per eye were safe and well tolerated in the eye and resulted in no detectable systemic effects in healthy adult volunteers.

This study evaluated the safety and efficacy of arformoterol and formoterol over 6-months in subjects with COPD. In a multi-center, 6-month randomized, double-blind, double-dummy trial, subjects with COPD (mean FEV(1) 1.21 L, approximately 41.0% predicted) were randomized to receive either nebulized arformoterol (15 microg BID [n = 149][ARF 15], 25 microg BID [n = 147][ARF 25]), or racemic formoterol (12 microg BID [n = 147][FORM]) delivered by DPI. The proportion of subjects with any post-treatment adverse event for ARF 15, ARF 25 microg, and FORM was 67.8%, 76.2% and 66.7%, respectively, and those with at least one COPD exacerbation was 32.2%, 30.6%, and 22.4%, respectively. Pulmonary function improved for all treatment groups and was maintained throughout the study. Mean change from baseline at 6-months for ARF 15, ARF 25 and FORM in peak FEV(1) was 0.30L, and 0.34L, and 0.26L, respectively, in 24-hour trough FEV(1) was, 0.10L, 0.14L, and 0.09L, and in inspiratory capacity was, 0.20L, 0.37L, and 0.23L. Dyspnea, (mean Transition Dypsnea Index (TDI) focal score) improved in all treatment arms (ARF 15: 1.4, ARF 25: 1.5, and FORM: 1.4) at 6 months, as did rescue short-acting beta(2)-agonists use (mean range: -1.1 to -1.3 actuations/day) and ipratropium bromide (mean range: -0.3 to -0.8 actuations/day). Health status, measured by St George's Respiratory Questionnaire, improved from baseline at 6-months in all treatment groups (mean change: -3.7 to -6.8). In this 6-month study, arformoterol and formoterol were well-tolerated, and their use was associated with improvement in pulmonary function and health status in subjects with COPD with no apparent development of tolerance.

BACKGROUND:Arformoterol is a single-isomer (R,R-formoterol) nebulized long-acting beta(2)-agonist approved for use in patients with chronic obstructive pulmonary disease (COPD). Exposure (plasma concentrations of (R,R)-formoterol) and forced expiratory volume in 1s (FEV(1)) were compared for 15 microg nebulized arformoterol and 12 and 24 microg racemic formoterol (containing 6 and 12 microg (R,R)-formoterol, respectively) delivered by dry powder inhaler (DPI). METHODS:An open-label, randomized, three-way crossover study in 39 subjects with COPD (FEV(1) 1.4L, 44.4% predicted). Twice-daily treatments included nebulized arformoterol (15 microg) and racemic formoterol DPI (12 and 24 microg) for 14 days. Plasma concentrations of (R,R)- and (S,S)-formoterol were determined on days 1 and 14 of each treatment period. Airway function efficacy endpoints included the percent change in trough FEV(1) from baseline on day 14 of each treatment period. RESULTS:At steady state, exposure to (R,R)-formoterol was similar following nebulized 15 microg arformoterol (C(max): 6.5 pg/mL; AUC(0-tau): 56.5 pgh/mL) and 12 microg racemic formoterol DPI (C(max): 6.2 pg/mL; AUC((0-)(tau)()): 46.3 pgh/mL). The geometric mean ratios between these two treatments (90% confidence intervals) for C(max) and AUC((0-)(tau)()) were 0.91 (0.76, 1.09) and 1.16 (1.00, 1.35), respectively. Treatment with 24 microg racemic formoterol DPI resulted in dose proportionally higher (R,R)-formoterol: C(max) (10.8 pg/mL) and AUC((0-)(tau)()) (83.6 pgh/mL). Detectable (S,S)-formoterol was consistently measured only after treatment with racemic formoterol. The mean percent increase in trough FEV(1) was 19.1% in the arformoterol group, and 16.0% and 18.2% in the 12 and 24 microg racemic formoterol groups, respectively. Changes in (R,R)-formoterol concentrations over time paralleled changes in FEV(1). CONCLUSIONS:In this study, plasma exposure to (R,R)-formoterol was similar for nebulized 15 microg arformoterol and 12 microg racemic formoterol DPI, and 40% lower than 24 microg racemic formoterol DPI. There was no evidence of chiral interconversion following treatment with arformoterol. Finally, temporal changes in airway function in all treatment groups corresponded to changes in (R,R)-formoterol plasma concentrations.

Background: The short-acting beta(2)-agonists levalbuterol and racemic albuterol are available for administration through a hydrofluoroalkane-134a (HFA) metered-dose inhaler (MDI).Objective: This study compared the short-term safety and efficacy of cumulative doses of levalbuterol HFA MDI and racemic albuterol HFA MDI in asthmatic subjects.Methods: This was a randomized, modified-blind, active-controlled, multicenter, 2-way crossover study. Subjects (n = 49) were randomized to 16 cumulative doses (I X, 2 X, 4 X, 8 X, and 16 X) of levalbuterol (45 mu g per dose) or racemic albuterol (90 mu g per dose) administered over a 2-hour period. After a 7-day washout period, subjects were crossed over to the other treatment. After each dose, safety outcomes and pulmonary function were assessed.Results: Heart rate and (R)-albuterol exposure increased for both racemic albuterol HFA and levalbuterol HFA. For cumulative doses of 8 x or greater, racemic albuterol HFA treatment had greater increases in mean heart rate than levalbuterol HFA (least-squares mean [ SD] difference at the 8 x dose was 2.8 beats/min [95% Cl, 0.3-5.3] and at the 16x dose was 3.5 beats/min [95% Cl, 0.6-6.41). (R)-albuterol plasma levels ranged from 10% to 18% higher after racemic albuterol HFA MDI dosing versus after levalbuterol HFA MDI. FEV(1) improvements were similar for both treatments. The relative potencies of the 2 therapies, based on FEV(1), were similar (ratio, 1.1 [90% CI, 0.9-1.2]; Finney method).Conclusion: In this study single-day cumulative dosing of asthmatic subjects with levalbuterol HFA MDI or racemic albuterol HFA MDI resulted in similar improvements in FEV(1) and tolerability. Plasma (R)-albuterol levels and mean heart rate were less with levalbuterol HFA MDI.

Beta-adrenergic stimulation may increase heart rate and the potential for cardiac arrhythmias. The effect of inhaled long-acting beta2-agonists (LABAs) on these outcomes was evaluated in patients with chronic obstructive pulmonary disease (COPD) in 2 double-blind randomized clinical trials. The pretreatment arrhythmia occurrence frequency in these patients was also described. In this analysis, 24-hour Holter monitoring data were pooled from 2 identically designed Phase III trials. Patients were randomized to LABA treatment or placebo for 12 weeks: a) nebulized arformoterol 15 microg BID, b) 25 microg BID, or c) 50 microg QD; d) salmeterol metered dose inhaler 42 microg BID; or e) placebo. The 24-hour Holter monitoring was performed pretreatment and at Weeks 0 (first day of dosing), 6, and 12. We assessed the proportion of patients with each of 4 arrhythmias: atrial tachycardia, atrial fibrillation/flutter, and "nonsustained"; (4-10 beats) and "sustained"; (>10 beats) ventricular tachycardia. There were 5226 Holter recordings in 1429 treated patients. At baseline, there was a low frequency of occurrence of atrial fibrillation/flutter (0.1%), nonsustained ventricular tachycardia (3.1%), and >10 beat ventricular tachycardia (0.3%). Atrial tachycardia occurred frequently (41.8%). The proportion of patients with treatment-emergent atrial tachycardia ranged from 27% to 32% and was non-significantly higher, by approximately 2%-5% (p = 0.70), in the LABA groups compared with the placebo group. The rates of the other more serious arrhythmias did not increase with LABA treatment and were similar to placebo. All treatment groups (LABA and placebo) had consistent small decreases from baseline in mean 24-hour and maximum hourly heart rate. In conclusion, in this large cohort of COPD patients with no or stable cardiac comorbidities, a high proportion ( approximately 40%) of patients were observed to have atrial tachycardia before treatment, which increased by 2%-5% with LABA treatment. More serious arrhythmias were infrequent and did not increase with inhaled LABA therapy. LABA administration did not increase mean heart rate.

Introduction: Concerns have been raised regarding the safety of extended use of long-acting β2-agonists (LABAs). The safety of arformoterol (50 µg QD), and salmeterol (42 µg BID), was assessed over 12 months in subjects with COPD. The study also examined the occurrence of tolerance with these agents, i.e. whether improvement in airway function diminished or frequency of exacerbations increased with 12-months of use. Methods: Subjects with COPD (mean FEV1 1.2 L, ~41% predicted) were enrolled in the study and randomized to receive nebulized arformoterol 50 µg QD (n = 528) or salmeterol 42 µg BID (MDI; n = 265) in a prospective, multicenter, open-label, 12-month trial. The frequency of adverse events, COPD exacerbations, and use of short-acting bronchodilator agents were assessed throughout the study period. Pulmonary function was also examined. Results: Among treated subjects, the frequency of adverse events was similar for those taking arformoterol (90.5%) and salmeterol (88.3%). Tremor was more frequent among subjects treated with arformoterol (13.4%) than those treated with salmeterol (1.1%). The frequency of COPD exacerbations did not increase over 12 months for arformoterol and salmeterol (weeks 0—13: 15.7% and 11.7%, respectively; weeks 39—52: 10.0% and 9.4%, respectively). Supplemental ipratropium bromide and rescue racemic albuterol use decreased for both groups by 0.8 to 1.5 actuations/day, decreases that remained stable throughout the 52-week study. Mean predose (trough) FEV1 improved for arformoterol and salmeterol at week 13 (7.1% ± 17.0 and 7.6% ± 17.8, respectively) and the improvement continued at week 52 (5.9% and 6.2%, respectively). Mean peak percent predicted postdose FEV1 over the course of the 52-week study declined by about 2% for both treatments, but throughout was higher for arformoterol than for salmeterol. Conclusion: In this trial, both arformoterol 50 µg QD and salmeterol 42 µg BID were well tolerated in patients with COPD. Both LABAs produced effective bronchodilation and their use was not associated with the development of clinically meaningful tolerance over a 1-year treatment period.

Rationale: Arformoterol, a single isomer long-acting β2-agonist, was developed as an inhalation solution for the maintenance treatment of bronchoconstriction in COPD. Methods: The pulmonary function efficacy of nebulized arformoterol (15 μ g BID, 25 μ g BID, 50 μ g QD) and salmeterol MDI (42 μ g BID) versus placebo was assessed in 1456 subjects (mean FEV1 1.2L, mean predicted 41%). Data were pooled from 2 identical, 12-week, double-blind, randomized trials. The percent change in trough FEV1, percent change in FEV1 average AUC(0 - 12 hrs) and peak percent change FEV1 from predose were analyzed. Results: Improvement in trough FEV1 averaged over 12 weeks was greater for arformoterol and salmeterol versus placebo (mean differences from placebo [95% CI] arformoterol–15 μ g BID: 11.4% [8.4, 14.3]; 25 μ g BID: 15.4% [12.2, 18.6]; 50 μ g QD: 10.9% [7.9, 13.9]); salmeterol: (11.6% [8.8, 14.4]). Greater improvements versus placebo occurred after the first dose (mean differences between arformoterol and placebo for trough FEV1: 13–19%; FEV1 AUC(0 - 12 hrs): 19–24%; peak percent change: 20–25%) and at week 12 (trough FEV1: 10–13%; FEV1 AUC(0 - 12 hrs): 6–13%; peak percent change: 7–14%); all 95% CIs excluded zero. Increases in FEV1 AUC(0 - 12 hrs) and peak percent change were greater for arformoterol than for salmeterol (95% CIs excluded zero). After 12 weeks, 78–87% of arformoterol subjects had ≥ 10% increases in FEV1 from pre-dose (56% salmeterol, 44% placebo); the median time to response was 3–13 minutes (142 minutes salmeterol). Conclusions: In these trials, COPD subjects administered nebulized arformoterol demonstrated significant and sustained improvement in lung function over 12 weeks.

PURPOSE: The long-term safety and efficacy of two long-acting β2-agonists (LABAs) arformoterol (administered via nebulization) and racemic formoterol DPI were compared in subjects with COPD in a multi-center, 6-month randomized, double-blind, double-dummy clinical trial.

Background: Previous studies have raised concerns regarding the safety of regular use of beta(2)-agonists for treating asthma. Few studies have explored the safety of at least 1 year of use of racemic albuterol, and none have examined long-term dosing of levalbuterol.Objective: To examine the long-term safety of levalbuterol hydrofluoroalkane (HFA) vs racemic albuterol HFA administered via metered-dose inhaler (MDI) in patients with stable asthma.Methods: Patients with mild to moderate asthma (mean forced expiratory volume in 1 second [FEV1], 68.3% of predicted) 12 years or older participated in a multicenter, parallel-group, open-label study. Patients were randomized to levalbuterol HFA MDI (90 mu g: 2 actuations of 45 mu g; n = 496) or racemic albuterol HFA MDI (180 mu g; 2 actuations of 90 mu g; n = 250) for 52 weeks of 4 times daily dosing. The primary end point was the incidence of postrandomization adverse events. Asthma exacerbations and pulmonary parameters were also assessed.Results: The overall incidence of adverse events was similar for levalbuterol (72.0%) and racemic albuterol (76.8%). Rates of P-mediated adverse events, serious adverse events, and discontinuations because of adverse events were low (< 15%) and were comparable between groups. Rates of asthma adverse events for levalbuterol and racemic albuterol were 18.3% and 19.6%, respectively. Mean percentage of predicted FEV1 improved after dosing and was stable for both groups.Conclusion: In this trial, up to 52 weeks of regular use of levalbuterol HFA MDI or racemic albuterol HFA MDI was well tolerated. and no deterioration of lung function was detected during the study period.