No surprise, is it? But the price of acquiring a promising med from a biotech is soaring. The cost has jumped by about 45 percent annually over the last three years, according to a Lehman Brothers research note, and drugmakers were promising an average of $400 million in potential milestone payments under licensing agreements.

The number of deals struck has remained essentially flat but there has been a marked growth in collaborations worth at least $500 million, Reuters reports. “We believe deal term inflation reflects large-cap pharma-biotech’s declining R&D productivity and growing reliance on in-licensing deals to maintain late-stage pipelines,” the firm wrote.

This year, one-third of deals with disclosed financial terms exceeded $500 million in total milestone payments, compared with less than 10 percent before 2005. Many of the big drugmakers, of course, are under increasing pressure to launch new meds to replace blockbusters lost to generic rivals. In fact, many of the world’s top-selling drugs facing patent expiration by 2012.