Market Insider

Markets watching out for Janet Yellen on Thursday, and now also Hillary Clinton

Countdown to Jackson Hole

Stock traders have been watching out for Janet Yellen all week, but they were blindsided by Hillary Clinton.

Fed watching should continue Thursday, as traders digest durable goods and jobless claims data ahead of Friday's Jackson Hole speech by the Fed chair. But they will also be licking their wounds after Democrat Clinton punctured the health-care sector with one powerful tweet Wednesday afternoon. The IBB Nasdaq Biotech ETF fell 3.4 percent, after Clinton tweeted and issued a statement saying that there's no justification for the high prices Mylan is charging for EpiPens.

Mylan has been under fire for the dramatic price hikes in EpiPens, livesaving devices for people with severe allergies. Prices have gone from $100 in 2008 to more than $600 for some customers.

Mylan responded Thursday by expanding existing programs to boost access to its EpiPen Auto-Injector for patients who have high out-of-pocket costs. The company is reducing the cost through the use of a savings card which will cover up to $300 for the EpiPen 2-Pak, and taking other stops. Mylan shares were more than 3 percent higher in early trading.