Forward Pharma A/S, of Copenhagen, said it filed a lawsuit against Biogen Idec GmbH, Biogen Idec International GmbH and Biogen Idec Ltd., units of Cambridge, Mass.-based Biogen Idec Inc., in the Regional Court in Dusseldorf, alleging infringement of its German utility model DE 20 2005 022 112 due to Biogen Idec's marketing of multiple sclerosis (MS) drug Tecfidera (dimethyl fumarate) in Germany.