As a case study of patent coverage for a repurposed drug, Biogen Idec's approach for Tecfidera(®), an oral formulation of dimethyl fumarate, was analyzed. While mixtures of fumarates have been used for over 50 years to treat psoriasis, Tecifidera is approved for the treatment of relapsing-remitting multiple sclerosis. Biogen pursued claims to pharmaceutical formulations and useful doses for treating multiple sclerosis, an approach that is relevant to pharmaceutical lifecycle management in general. A survey of recent US, EP, and PCT patent applications indicate other companies are developing competing fumarate formulations. While it is possible to pursue secondary patents for compounds without composition of matter coverage, regulatory data exclusivity provides additional protection to delay competitors.