Boxed warnings for Amgen/Wyeth's Enbrel

US biotechnology major Amgen and drugmaker Wyeth say that the Food and Drug Administration-approved prescribing information for Enbrel (etanercept) now contains a boxed warning relating to the risk of infections, including tuberculosis, which is similar to labeling for other medicines in the tumor necrosis factor-inhibitor class. The PI had previously included a bolded warning regarding the risk of infections and tuberculosis. This information is now in a boxed warning and includes language on screening and monitoring patients for tuberculosis, including those who tested negative for latent infection.

In addition, the boxed warning states that tuberculosis has been observed in patients receiving TNF-blocking agents, including Enbrel, and that the disease may be due to reactivation of latent or new infection. The warning notes that data from clinical trials and preclinical studies suggest that the risk of reactivation of latent tuberculosis infection is lower with Enbrel than with TNF-blocking monoclonal antibodies, the firms noted, although post-marketing cases of tuberculosis reactivation have nonetheless been reported for TNF blockers, including Enbrel. The risks defined in the boxed warning are consistent with those of tuberculosis and infections that have been included in previous versions of the US label. The drug, which is used to treat rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis and plaque psoriasis, had fourth-quarter 2007 sales of $856.0 million.