Marathon Pharmaceuticals has frozen the rollout of muscular dystrophy drug Emflaza, its brand name for deflazacort, after taking significant criticism over its pricing plan for the drug. Emflaza received regulatory approval for U.S. sales last week. Marathon CEO Jeffrey Aronin said in a statement, “We have not sold any new product, and we will pause that process.” The company didn’t say when it expected to make the drug commercially available.

Deflazacort is a corticosteroid used to treat Duchenne muscular dystrophy, a progressive muscular degeneration condition. The condition afflicts fewer than 15,000 people, mostly males. Marathon did not develop deflazacort, but did acquire the rights to clinical trial data on the drug and completed additional analyses necessary to secure approval from the Food and Drug Administration for sale in the U.S.

Many have said that Marathon’s price for deflazacort is unjustifiably high because it’s been available outside the U.S. for years at considerably lower prices. Deflazacort has long been available to patients in the European Union and Canada and American patients and their parents have been importing deflazacort for decades. The drug currently costs less than $1,500 a year elsewhere, but Marathon planned to sell the drug in the U.S. for $89,000 for a year’s course of treatment.

Marathon was quickly vilified for its plan to raise the price of the drug so dramatically. Two members of Congress, Senator Bernie Sanders and Representative Elijah Cummings, wrote a letter to the company expressing their indignation about its “outrageous” planned price. They also asked for information on how Marathon set the price and what profits are expected by Feb. 27.

In an open letter, Marathon wrote that the resources it invested in getting the drug approved in the U.S. “were substantial and we don’t expect to recoup our investment for several years.” The company pledged to reinvest the earnings from Emflaza into more research in Duchenne muscular dystrophy if the drug proves profitable. The company also said in its statement that American patients who currently receive the drug from other sources “will continue to have that option.”

Marathon said it expects patients in the U.S. to pay “a standard co-pay of typically $20 or less per prescription” in its letter. The company will also maintain an expanded access program that provides the drug for free to 800 patients. Marathon believes that access to the drug “will be dramatically expanded” once it’s commercially available in the U.S.

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