Insmed Inc (INSM)

[jellybean]

A good source of information for approved drugs are the FDA approval documents.

Iressa was selected by scientists at Astra Zeneca as an inhibitor of Epidermal growth factor cell surface receptor (EGFR) which stimulates the growth of epidermal (including epithelial) cells. EGFR was the first receptor protein shown to be a tyrosine kinase and many tumors overexpress epidermal growth factor receptor. Hence, Astra-Zenca's interest.

The problem is that iressa is not specific. The molecule is an ATP mimetic and works by binding to the ATP binding site of the receptor. There are many other tyrosine kinases in acell to which Iressa will bind including vascular endothelial growth factor and platelet derived growth factor.

You are absolutely right in that there are a lot of kinases and a lot of companies with kinase inhibitors. The success or failure of any such compound really depends upon its specificity and ability to reach its target. Until more is known about INSM-18 any discussion is moot. The one important point, though, is that Insmed is moving forward and not just focusing on one single drug -- even though it is a fantastic drug.