Ebb & Flow

The pair of life sciences companies on IPO road shows may give investors and other companies clues on the opening of an IPO window. Profitable plasma-derived protein company Talecris Biotherapeutics Inc. may price this week, while Phase III pharmacosurgery play Omeros Corp. is looking to get out early in October.

Omeros is the first development stage company to test the waters, with a tentative IPO date around Oct. 8. The company has three clinical candidates, all of which are combinations of generics for use as additives to standard surgical irrigation solutions...