UPDATE 1-Biogen profit beats Wall Street view on Spinraza sales

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Oct 24 (Reuters) - U.S. drugmaker Biogen Inc on Tuesday reported a higher-than-expected quarterly profit, driven by demand for its recently approved spinal muscular atrophy drug, Spinraza.

Net income attributable to Biogen rose to $1.23 billion, or $5.79 per share, in the third quarter ended Sept. 30, compared with $1.03 billion, or $4.71 per share, a year earlier.

Sales for Spinraza were $271 million, beating consensus estimates of $249 million, compiled by SunTrust Robinson Humphrey.

Excluding items, Biogen earned $6.31 per share, above analysts' estimates of $5.73 per share, according to Thomson Reuters I/B/E/S.

Total revenue rose to $3.08 billion from $2.96 billion.

The U.S. biotechnology company's bestseller Tecfidera saw sales of $1.07 billion, slightly below consensus estimates of $1.09 billion, as Biogen deals with more competition in the multiple sclerosis space.

Last year, the U.S. Food and Drug Administration approved Spinraza to treat spinal muscular atrophy, a rare disorder and the leading genetic cause of death in infants. (Reporting by Akankshita Mukhopadhyay and Manas Mishra in Bengaluru; Editing by Martina D'Couto, Bernard Orr)