CHARLESTON, W.Va. — U.S. Sen. Joe Manchin says he's concerned about skyrocketing prices for life-saving allergy injection pens made by a company headed by his daughter.

In a news release Thursday, the West Virginia Democrat says he plans a detailed review of drugmaker Mylan's response to criticism about the cost of EpiPens.

Manchin's daughter, Heather Bresch, is CEO of Mylan. She told CNBC Thursday that lowering the price wasn't an option.

Manchin says he plans to work with others to reduce prescription drug prices.

According to the Elsevier Clinical Solutions' Gold Standard Drug Database, a two-dose package that cost around $94 nine years ago has risen more than 500 percent to an average cost of $608 in May. The hike has been criticized by Democratic presidential candidate Hillary Clinton and members of Congress.

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