Lirimilast (BAY 19-8004) is a potent, selective and orally active phosphodiesterase-4 (PDE4) inhibitor with an IC50 value of 49 nM. Lirimilast can be used for the treatment of asthma or chronic obstructive pulmonary disease (COPD). Lirimilast has potently anti-inflammatory properties[1][2].
In PDE4 assays Lirimilast (BAY 19-8004) is reported to be 5-fold more potent than Cilomilast and equipotent with CDP-840 using freshly prepared PDE4 from human PMNL[1].
Since Lirimilast (BAY 19-8004) is orally active in the guinea-pig at 3 mg/kg and, more critically, in primates at 0.1 mg/kg/day it appears to have a good therapeutic ratio. In addition Lirimilast is found to be 3-fold more potent than Cilomilast when compared in a rat model of lung neutrophilic inflammation[2].
[1]. Grootendorst DC, et al. Efficacy of the novel phosphodiesterase-4 inhibitor BAY 19-8004 on lung function and airway inflammation in asthma and chronic obstructive pulmonary disease (COPD). Pulm Pharmacol Ther. 2003;16(6):341-7. [2]. Peter Norman. PDE4 inhibitors: sustained patenting activity as leading drugs near the market. Exp. Opin. Ther. Patents (2000) 10(9):1415-1427.