The S&P 500 was down 0.3% in midday trading to 2,763.44.
The Dow Jones Industrial Average rose 0.2% to 25,187.15.
The Nasdaq was down 1% to 7,608.00.
The yield on a 10-year Treasury bond plunged 1.8% to 2.92%.
The price of gold was flat at $1,302.
Glaukos Inc. (NYSE: GKOS) in San Clemente was down 4.2% to $37.31 and a $1.3 billion market cap. It makes a stent to treat glaucoma.
PharmaCyte Biotech Inc. (OTC: PMCB) in Laguna Hills was up 10.9% to 6 cents and a $61 million market cap. It’s developing cellular therapies for cancer and diabetes.
Nemus Bioscience Inc. (OTC: NMUS) in Costa Mesa was up 6.5% to 33 cents and a $44 million market cap. It’s developing cannabis-based drugs to treat glaucoma and chemotherapy-induced nausea, among others.