Wyeth has been granted approval in the European Union for a new, once-weekly formulation of Enbrel (etanercept), its biologic drug for moderate to severe rheumatoid arthritis.

The once-weekly formulation, which delivers 50mg of the active drug, will be sold alongside the current dosing regimen. At the moment Enbrel is given in two 25mg injections three to four days apart, but the new label allows both injections to be taken on the same day, according to the European Medicines Agency.

The EMEA approval is based on two clinical studies which showed that the efficacy and side-effect profile were similar between the two dosing options in patients with RA. The once-weekly dosing regimen was approved in the USA in 2003.

The new dose will help Enbrel maintain its growth momentum against rival biologics for RA that require les frequent dosing, notably, Abbott Laboratories’ fast-growing Humira (adalimumab) that needs to be dosed only once very other week [[13/04/05d]].

Enbrel (etanercept) – which Wyeth co-promotes in North America with Amgen and has exclusivity elsewhere – achieved first quarter 2005 revenues of $237 million, a rise of 75%, helped by its recent approval for psoriasis [[21/04/05a]].