Biogen Still Has Competitive Advantages in Neurology, but Its Moat Looks Narrow

We think Biogen's neurology, immunology, and focus on rare diseases support a narrow moat. Biogen's strategy has its roots in the 2003 merger of Biogen (multiple sclerosis drug Avonex) and Idec (cancer drug Rituxan). The firm expanded its neurology portfolio beyond MS, including the blockbuster rare neuromuscular disease drug Spinraza. We see Biogen as a firm in transition, as MS revenue fades and launches of several new drugs for Alzheimer's, depression, and rare diseases begin to ramp up.