Pranlukast (Onon, Azlaire), is an orally administered, selective, competitive antagonist of the cysteinyl
leukotrienes (LT) C(4), LTD(4) and LTE(4). It is indicated for the prophylactic treatment of chronic
bronchial asthma in paediatric and adult patients. The efficacy of
pranlukast 225mg twice daily in adults with mild to moderate
asthma was demonstrated in double-blind, placebo- or
azelastine-controlled studies of 4 or 8 weeks' duration. The
drug at this dosage was superior to both comparators in improving mean attack scores and morning and/or evening peak expiratory flow rates, and decreasing the use of rescue
bronchodilators (p < 0.05). In limited clinical studies,
pranlukast 225mg twice daily appeared to be as effective as
montelukast 10mg once daily and
zafirlukast 40mg twice daily in adults with mild to moderate
asthma. Tachyphylaxis was absent when the
drug was administered for up to 4 years. In patients requiring high-dose inhaled
corticosteroid therapy,
pranlukast 225 mg twice daily plus a halved dosage of inhaled
corticosteroid was as effective as the original dosage of inhaled
corticosteroid.
Pranlukast was also effective in patients with mild to severe
asthma in a clinical practice setting. In a double-blind trial, greater improvements in most outcome measures were observed with
pranlukast than with
oxatomide in children and adolescents with
asthma. In clinical trials,
pranlukast was well tolerated in adult and paediatric patients with
asthma, with an adverse event profile similar to that of placebo. Gastrointestinal events and hepatic function abnormalities were the most commonly reported adverse events. No clinically significant differences in adverse event profiles between
pranlukast,
zafirlukast or
montelukast were shown in limited comparisons. Although
Churg-Strauss syndrome has been noted in
pranlukast recipients, a direct causal relationship is unlikely.
CONCLUSIONS:
Pranlukast is a well tolerated and effective preventative treatment in adult and paediatric patients with persistent
asthma of all severities. In some patients,
pranlukast may be beneficial when added to low-dose inhaled
corticosteroids; it may also be a viable alternative to increasing inhaled
corticosteroid dosages. The efficacy of
pranlukast relative to placebo has been confirmed; its efficacy relative to other
therapy awaits further investigation. Nonetheless,
pranlukast is a useful therapeutic option (with as-required short-acting beta(2)-agonists), either as preventative monotherapy for the treatment of mild persistent
asthma or in conjunction with inhaled
corticosteroids in the management of moderate or severe persistent
asthma.