The S&P 500 rose 0.22% to 1,882.28 in afternoon trading Thursday.
The Dow Jones Industrial Average was up 0.43% to 16,590.37, while the Nasdaq was up 0.31% to 4,080.38.
The yield on a 10-Year treasury bond rose 0.73% to 2.61%.
The price of gold fell 0.02% to $1,288.70 per ounce.
Aliso Viejo-based drug maker Avanir Pharmaceuticals Inc. rose about 7% to $4.74 for a market value of $721.88 million. The company reported earlier this week a narrowed loss in the March quarter as a result of growth in revenue of its Nuedexta drug.
Newport Beach-based medical imaging provider Alliance Healthcare Services Inc. rose about 11% to $31.54, a day after reporting quarterly results that included 13% growth of the oncology business to $20.7 million. Alliance had a recent market value of $331.82 million.