Mylan, manufacturer of the allergic reaction treatment EpiPen, has announced it will sell a generic version of the autoinjector at half the price of the branded device after federal lawmakers and consumer groups questioned why its price has gone up 400 percent since Mylan acquired it.

The generic EpiPen will be sold for $300 for a two-pack, roughly half the current list price for the branded version.

“We understand the deep frustration and concerns associated with the cost of EpiPen® to the patient, and have always shared the public's desire to ensure that this important product be accessible to anyone who needs it,” said Mylan CEO Heather Bresch. “Our decision to launch a generic alternative to EpiPen is an extraordinary commercial response, which required the cooperation of our partner. However, because of the complexity and opaqueness of today's branded pharmaceutical supply chain and the increased shifting of costs to patients as a result of high deductible health plans, we determined that bypassing the brand system in this case and offering an additional alternative was the best option.”

Bresch initially tried to deflect criticism about the rapid price increase since Mylan acquired EpiPen in 2007, saying she was frustrated over the hikes and blaming high-deductible insurance plans and high co-pays for prescription drugs. The company argued its provided more than 700,000 free EpiPens to schools and increased access by offering “savings card” to customers.

The controversy eventually reached Bresch’s father, U.S. Sen. Joe Manchin, D-West Virginia, who said he expected Congress to address the price issue when members return to Washington, D.C., in September.

These efforts didn’t satisfy consumer advocacy groups like Public Citizen, which attacked Bresch’s $19 million salary and Mylan’s corporate inversion of moving its headquarters to the Netherlands for tax purposes.

The announcement of the generic offering didn’t change the group’s tone, with Public Citizen President Robert Weissman calling it “not good enough.”

“The weirdness of a generic drug company offering a generic version of its own branded but off-patent product is a signal that something is wrong,” he said. “In short, today’s announcement is just one more convoluted mechanism to avoid plain talk, admit to price gouging and just cut the price of EpiPen.”

Weissman said the generic version’s price is still above what EpiPens sell for in other countries. Two-packs in France, for instance, go for around $100.

Members of Congress aren’t leaving Mylan alone, either. On the same day the company announced the generic version, Reps. Jason Chaffetz, R-Utah, and Elijah Cummings, D-Maryland, of the House Committee on Oversight and Government Reform, sent a letter to Bresch requesting documents on EpiPen sales, company profits and how much Mylan has spent on lobbyists for state and federal governments.

“While families and schools are struggling to keep up with your company’s unreasonable price increases, Mylan has profited richly from its pricing strategy,” Chaffetz and Cummings wrote.

The lawmakers requested Mylan submit the requested documents by Sept. 12.