Biogen Idec and Isis Pharmaceuticals have entered into an exclusive, worldwide option and collaboration under which the companies will develop and commercialize Isis’ antisense investigational drug, ISIS-SMNRx, for the treatment of spinal muscular atrophy (SMA). SMA is a genetic neuromuscular disease characterized by muscle atrophy and weakness, and it is the most common genetic cause of infant mortality. Isis’ ISIS-SMNRx is designed to compensate for the underlying genetic defect that causes SM...