Therapy Analysis - Asthma
Targeted approaches
Of the 170-plus asthma drugs in active development which have known target family groups, the receptor target family accounts for over 50% of these (graph 2). This family encompasses the inhaled glucocorticoids. Of the 25 glucocorticoids listed on Pharmaprojects that are launched for asthma, 14 of these are inhalable, including beclometasone, formulations of which are in development by a variety of companies, and budesonide, which has been developed by AstraZeneca.
In addition, there are 22 glucocorticoids in active development for asthma. Also featuring in this family with predictable popularity are the B2AR agonists, with 30 launched and 30 in active development. While the pros and cons of these two therapies are debated, pharmaceutical research has moved to look for alternative treatments. Success has been found with montelukast sodium, a GPCR-targeted drug that inhibits leucotriene D4, which is launched for the treatment of ASA-sensitive and exercise-induced non-atopic asthma.
Graph 2 illustrates that enzymes are the second most common target family group for asthma. Of these, PDE4 inhibition is the most frequent strategy employed, which is no surprise considering the improvements that have been made to make this therapeutic target a viable option. In the late 1980s and early 90s, research into GPCR-antagonistic and PDE4-inhibiting drugs for other indications, such as depression,..enzymes are the second most common target family group for asthma.. revealed that by inhibiting PDE4 specifically, the major adverse events typical of general PDE4 inhibitors were avoided. Altanta's roflumilast is certainly one of the more well known PDE4 inhibitors, currently in Phase III trials. Its future is uncertain however - although it has proved safe and efficacious, a filing in the EU was withdrawn in 2004 'pending further clinical data', which has not yet been released. More successful is Kyorin's ibudilast, which has been launched for many years in Japan, while additional candidates are in clinical development, including Celgene's CC-10004, which is currently in a Phase II trial, with results expected in the second half of 2006. Glenmark's oglemilast is in US Phase II trials, with additional trials planned.
