First a definition. According to the Sino-American Biomedical and Pharmaceutical Professionals Association (SABPA) in a 2006 pdf, biologics are protein or carbohydrate based, extracted from a living entity, posessing a complex physicochemical structure, and are defined by the manufacturing process link here. In 2005, it reports the five leading drugs sold under Part B of Medicare were biologics, valued at more than $4 billion.
In what follows, I am uncertain that I have matters right, but here goes. According to SABPA, biologics cannot be regulated as generics since they can't be shown to be chemically identical to previous approved drugs--the chemicals may be the same, but their structure differs. They must therefore have efficacy and safety data submitted separately, an expensive and time-consuming process. This is the Pharmas justification for asking that a patent's life be extended.
The SABPA definition is notable in that it seems to open the way for defining and patenting such a drug according to one or more of these terms, an almost infinite set of possible patents. The big Pharmas mouths must be watering.
The issue according to Weintraub is whether TEVA and other generic makers, can limit the patent extension beyond the initial monopoly or whether the extension is granted for 10 or more years as the big Pharmas would like. "Right now, the U.S. Food & Drug Administration has no mechanism for reviewing or approving these complex medicines. But several bills introduced this year seek to clear the way and Teva Pharmaceuticals, the world's largest generic-drug manufacturer, is working like mad to make it happen."
Mike Masnick fails to see any justification for a longer patent. He has written on the subject several times, most recently here link here.
Given the amounts of money and the importance of controlling health care costs, we are sure to hear more on this.