WESTON, Mass. ( TheStreet) -- Biogen Idec ( BIIB) second-quarter earnings exceeded Street estimates, helping the company raise its 2010 earnings outlook, although sales of its multiple sclerosis drug Tysabri were weaker than expected. Adjusted earnings for the quarter were $1.31 a share, above the consensus estimate of $1.12 a share. On a GAAP basis, Biogen earnings rose 129% to 1.12 cents a share. Total revenue in the quarter was $1.2 billion up 11% year over year and above investors' consensus estimate of $1.13 billion. Worldwide Tysabri sales of $298 million in the second quarter fell below the consensus estimate of $307 million. About 185 multiple sclerosis patients per week began treatment with Tysabri in the second quarter, up from 146 patients per week in the first quarter. Sales of Avonex, Biogen's other multiple sclerosis drug, totaled $628 million in the first quarter, well ahead of the Street's $573 million forecast. Biogen raised guidance for adjusted 2010 earnings to $4.70 a share, above the current consensus of $4.57 a share. On a GAAP basis, Biogen said 2010 earnings would be $3.82 a share. During the second quarter, Biogen repurchased 20.8 million shares for $1 billion under a previously announced share repurchase program. In total since the beginning of the year, Biogen has repurchased 36 million shares for $1.8 billion. Biogen shares closed Monday at $53.18. -- Reported by Adam Feuerstein in Boston. Follow Adam Feuerstein on Twitter.