WASHINGTON (AP) — Amgen Inc., the world’s largest biotechnology company, spent nearly $2.8 million lobbying in the first quarter as Congress debates a potential system for bringing less expensive copies of pricey biotech drugs to the market. Legislation that could allow the Food and Drug Administration to approve copies of biotech drugs may have the biggest impact on Amgen. An approved biosimilar process would open the door for competition from copies of its drugs and eventually cut into sales. Thousand Oaks, Calif.-based company Amgen had revenue of $3.31 billion in the first quarter, mainly on sales of the blockbuster rheumatoid arthritis and psoriasis drug Enbrel, anemia drug Epogen, and Neulasta, which prevents infections in chemotherapy patients. The patent for Enbrel, which is sold with partner Wyeth, expires in 2009. But without a process for approving copies of biotech drugs, Enbrel will not face generic competition in the U.S. Biotech companies and generic drug developers have been at odds over the what a system for copies of biotech drugs should look like. Biotech firms want longer patent protection while generic companies are asking for a timeline similar to the current system for chemical compounds. Legislation before Congress currently call for either 5 years or 14 years of competition-free sales, with the biotech industry favoring the longer period. The FDA regulates the approval of generic drugs made from chemical compounds, but does not have a system in place for similar versions of biotech drugs, which are developed using more complicated, living cells. Amgen also lobbied on patent reform and Medicare reimbursement rates in the January-March period, according to the disclosure form filed April 20 with the House clerk’s office