Montelukast was launched as Singulair in Mexico and Finland for the
management of mild to moderate asthma inadequately controlled by inhaled
corticosteroids and short-acting beta2-agonists. Montelukast can be obtained by
an seven-step synthesis from 3-[2(E)-(7-chloroquinolin-2-yl)vinyl] benzaldehyde.
Montelukast is a potent, selective and orally active antagonist of the CysLT1
(formerly called LTD4) receptor, thus blocking the effects of the cysteinyl
leukotrienes LTC4, LTD4 and LTE4 on microvascular permeability and the
activation of eosinophils. Montelukast represents the third molecule of this class
which has been approved in asthma after pranlukast (1995) and zafirlukast
(1996). Montelukast has been studied extensively in placebo-controlled clinical
trials, in mildly or severe asthmatic patients challenged with LTD4 or exercise. A
variety of acute bronchoconstricting challenges were inhibited or attenuated with
all doses used. Montelukast demonstrated clinically significant improvements in
the parameters of asthma control associated with an appreciable improvement
in quality of life., reducing days with asthma exacerbations and allowing
significant tapering of corticosteroids. Montelukast is well-tolerated and only
needs to be administered once a day.
