epipens
The rising price of EpiPens may be leaving children with severe allergies at risk. Getty Images/Dick Loek/Toronto Star

Shares of Mylan NV are trading at historically low valuations as the company's chief executive officer is set to face a congressional grilling on Wednesday over the price of its EpiPen emergency allergy treatment.

The stock is trading at 7.5 times estimated earnings for the next 12 months, holding near its lowest in at least 30 years and well below its five-year average of 11 times, according to Thomson Reuters Datastream.

Since late August, when the EpiPen price increases came into the spotlight, Mylan shares have fallen about 15 percent. For the year, they are off about 23 percent, against a nearly 4 percent decline for the NYSE Arca Pharmaceutical index, a broad gauge of large and small drugmakers.

A test for the shares looms on Wednesday, when Mylan CEO Heather Bresch testifies before the U.S. House of Representatives Oversight Committee over price increases of EpiPen, an auto-injector of allergy medicine.

The hearing will come the day after West Virginia disclosed an investigation into whether Mylan violated antitrust laws or defrauded the state's Medicaid program. A probe into EpiPen pricing by a U.S. Senate subcommittee was also announced on Sept. 7.

The stock "is just not working because of the overhang from all the headline stuff on EpiPen," said Guggenheim Securities analyst Louise Chen, who rates the shares "neutral".

One concern among analysts is how fallout over EpiPen pricing will affect Mylan's roughly $1 billion in annual sales of the device.

Mylan said last month that it would introduce the first generic version of EpiPen for $300, half the price of the branded product, as it tries to quell the backlash. Further competition looms from Teva Pharmaceutical Industries, which hopes to start selling an EpiPen-like device by 2018.

Chen also said investors were unsure of the benefits from Mylan's recently completed $7 billion acquisition of Swedish drugmaker Meda, which some had deemed expensive.

Deutsche Bank analyst Gregg Gilbert stuck to his "buy" rating on Mylan stock earlier this month, noting its valuation.

But in a research note, Gilbert cautioned: "Investors will have little patience if execution falters on the base business and/or the newly acquired Meda business."