UPDATED: 3:42 p.m.

    Manufacturers of generic drugs seem finally to have a golden opportunity to enter the huge biological-drug market as patents expire on more than $10 billion of brand-name pharmaceuticals.
    However, they have two major hurdles to overcome: Congress must create an approval process for generic versions of the complicated and expensive drugs; and Congress may require price-prohibitive clinical trials if it approves generics.
    Unlike chemically derived medications, biologics are made from living cell tissue and are used to treat rare disorders, making them far more expensive than conventional pharmaceuticals and more difficult to replicate. Avastin, a colorectal cancer biological made by Genentech, can cost patients $5,500 a month.
    An approval process does not exist, based on the premise that the drugs are too complicated to duplicate and thus ensure their safety.
    Sen. Edward M. Kennedy, Massachusetts Democrat, has scheduled a vote for June 27 in the Senate Health, Education, Labor and Pensions Committee on a bill that would require the Food and Drug Administration to create an approval process for generic biologics.
    The legislation, sponsored by Sens. Charles E. Schumer and Hillary Rodham Clinton, both New York Democrats, opens an approval process that does not require manufacturers to conduct lengthy and costly clinical trials on generic biologics. However, Mr. Kennedy and local biotech leaders favor such trials, which are required in Europe.
    Barr Pharmaceuticals and Teva Pharmaceuticals, two of the leading generic-drug manufacturers in the country, have been sizing up the biologic market for years and say they have the ability to create generic versions of biologics and sell them at cheaper prices. Each company has a generic version of a human growth hormone or insulin product in its pipeline, just waiting for the door to open as it did in Europe several years ago.
    "I believe a federal approval process for biosimilar drugs is long overdue and will happen soon," said Bruce Downey, chief executive officer of Barr Pharmaceuticals. "It will not only save consumers billions of dollars a year but will allow more patients access to these important medications."
    Mr. Downey is leading a coalition of drug companies, businesses and advocacy groups that include AARP, Ford Motor Co. and General Motors Corp. to lobby Congress to open the biotech industry to generic competition.
    Biological drugs appeared 20 years ago on the U.S. market but did not immediately make a significant impact. In fact, the biological drug market barely existed in 2004. But over the past several years, the drugs have taken off, with sales expected to reach $90 billion by 2009.