Safety of regadenoson, an adenosine A2A receptor agonist for myocardial perfusion imaging, in mild asthma and moderate asthma patients: a randomized, double-blind, placebo-controlled trial.
BACKGROUND
Patients with reactive airways are at risk for adenosine-induced bronchoconstriction, mediated via A(2B) and/or A(3) adenosine receptors.


RESULTS
To examine the effects of regadenoson, a selective adenosine A(2A) receptor agonist, on airway resistance, we conducted a randomized, double-blind, placebo-controlled crossover trial in asthmatic patients with a positive adenosine monophosphate challenge test. The mean ratio of the forced expiratory volume in 1 second (FEV(1)) at each tested time point relative to the baseline FEV(1) was significantly higher after treatment with regadenoson compared with placebo from 10 to 60 minutes after treatment. One patient had a substantial but asymptomatic FEV(1) reduction (-36.2%) after regadenoson that reversed spontaneously. The most common adverse events with regadenoson were tachycardia (66%), dizziness (53%), headache (45%), and dyspnea (34%). The mean heart rate significantly increased with regadenoson (maximum of +10.4 beats/min) versus placebo.


CONCLUSIONS
In this pilot safety study of 48 patients with mild or moderate asthma who had bronchial reactivity to adenosine monophosphate, regadenoson was safe and well tolerated.
Pulmonology, Heart and Lung Centre, London, England.
Brian R
BR
Leaker
B
B
O'Connor
Trevor T
TT
Hansel
Peter J
PJ
Barnes
Lixen
L
Meng
Vandana S
VS
Mathur
Hsiao D
HD
Lieu
D058917:Adenosine A2 Receptor Antagonists; D000328:Adult; D001249:Asthma / Q000150:complications / Q000175:diagnosis*; D003324:Coronary Artery Disease / Q000150:complications / Q000175:diagnosis*; D004311:Double-Blind Method; D005080:Exercise Test / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015990:Placebo Effect; D011687:Purines / Q000008:administration & dosage / Q000009:adverse effects*; D011720:Pyrazoles / Q000008:administration & dosage / Q000009:adverse effects*; D012120:Respiration Disorders / Q000139:chemically induced* / Q000175:diagnosis; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome
D058917:Adenosine A2 Receptor Antagonists; D011687:Purines; D011720:Pyrazoles; C430916:regadenoson