When an expensive new product is approved to treat a chronic disease for which other treatments are relatively cheap, the question becomes one of whether third party payers will meet the demands of patients and physicians for the additional clinical benefit that the treatment provides.

Immunex Corp.'s Enbrel etanercept, a soluble receptor targeting tumor necrosis factor (TNF), is a breakthrough biotechnology treatment for rheumatoid arthritis (RA). However at roughly $11,400 per year, reimbursement for Enbrel could determine how widely it is prescribed.