FILE PHOTO: A sign marks a Biogen facility in Cambridge, Massachusetts, U.S. January 26, 2017. REUTERS/Brian Snyder

(Reuters) – Drugmaker Biogen Inc reported a 20 percent rise in first-quarter profit on Wednesday, driven by higher sales of its muscle disease treatment Spinraza.

Spinal muscular atrophy treatment Spinraza brought in $518 million in the quarter, beating Refinitiv IBES estimates of $486.4 million.

Multiple sclerosis drug Tecfidera, which brought in $999 million in the quarter, missed estimates, and faces several challenges to its intellectual property, which is key to shielding the blockbuster drug from generic competition.

Net income attributable to the company rose to $1.41 billion, or $7.15 per share, in the quarter ended March 31, from $1.17 billion, or $5.54 per share, a year earlier. (