The S&P 500 fell 0.07% to 3,849.03 in midday trading.
The Dow Jones Industrial Average was down 0.1% to 31,148.50, while the Nasdaq increased 0.2% to 13,486.13.
Crude oil declined 0.7% to $52.95 a barrel.
Gold was down 0.2% to $1,862.80.
The yield on a 10-year Treasury increased 1.3% to 1.104%.
HEALTHCARE
Axonics Modulation Technologies Inc. (Nasdaq: AXNX) increased 6.1% to $53.88 and a $2 billion market cap. Shares of the Irvine-based medical device maker have climbed 26% since last month.
OncoCyte Corp. (NYSE: OCX), a designer of lung cancer tests, rose 16% to $4.79 per share for a market cap of $321 million. The Irvine-based firm announced Wednesday its two largest investors purchased $25 million of common shares in a registered offering priced at $3.42 per share.
ENERGY
Newport Beach-based Clean Energy Fuels Corp. (Nasdaq: CLNE) fell 5% to $10.07 and a $2 billion market cap. Shares of Clean Energy, which supplies renewable natural gas, have more than doubled since December.