The first biosimilar versions of complex biologic drugs are expected to be approved for U.S. sales in the next few years, erasing their monopoly and cutting their sales just as generic pills reduce sales of brand-name ones.
Clark said he thinks Amgen is trying to build name recognition ahead of that for the two products, which are more likely than Amgen's other products to be requested by patients.
The Enbrel TV commercials feature golfer Phil Mickelson, while the Prolia commercials, which started recently, feature actress Blythe Danner worrying about "breaking a leg" as she goes on stage for a performance.
Sales rose 9 percent in the quarter to $1.34 billion for Neulasta and Neupogen, for treating a decline of infection-fighting white blood cells caused by cancer and other disorders. Enbrel sales jumped 7 percent to $938 million, and sales of three smaller drugs climbed by double-digit percentages.
Prolia and a similar drug, Xgeva for preventing fractures in cancerous bones, both saw sales more than triple from a small base to a combined $241 million.
But the sharp sales decline continued for blockbuster anemia drugs Aranesp and Epogen, which have had limits put on dosing and reimbursement due to safety concerns. Epogen was down 17 percent to $446 million and Aranesp fell 11 percent to $518 million.
Amgen reiterated its 2012 adjusted profit forecast of $5.90 to $6.15 per share. Analysts predict $6.08 per share, on average.
Linda A. Johnson can be followed at http://twitter.com/LindaJ_onPharma