Updated from 11: 46 a.m. EDT
Merger and acquisition news emanating from the pharmaceutical sector boosted many biotech and health care indices to start the week.
( MEDI) said it will be acquired by pharmaceutical-maker
for more than $15 billion. MedImmune surged 17.8% to $56.57, while AstraZeneca slumped 5.3% to $55.94.
The jump in MedImmune's shares powered the Amex Biotechnology Index by 1.5% and the Nasdaq Biotechnology Index by 1.3%.
The acquisition wasn't the only news AstraZeneca was making Monday. Shares of
( AGIX) slid more than 15% after AstraZeneca ended its collaboration in the development of the cardiovascular therapy AGI-1067. In March, AtheroGenics said the treatment failed to lower heart disease risk in a phase III clinical trial.
Recently, AtheroGenics was falling 56 cents, or 15.3%, to $3.09.
Among other winners,
continued its run higher. Avanir said Monday that it now expects a fiscal second-quarter loss of $11 million, compared with a year-ago loss of $13.9 million. Avanir, which surged more than 265% last week, was up another 12 cents, or 2.7%, to $4.52.
climbed 11.2% to $16.78,
was higher by 4.8% at $48.86, and
added 2% to $15.24.
Several ratings changes were sinking pharmaceutical names. Prudential cut its rating for
to neutral from overweight. Pfizer closed down 2.3% to $26.35.
eased 1.1% after Needham & Co. downgraded the stock to hold from buy.
Among other losers,
lost 0.7% to $49.60,
shed 1.5% to $59.63, and
was down 0.7% to $16.09.