Last week, the Food and Drug Administration announced that a drug previously not officially available to patients in the United States had been approved. Deflazacort, a corticosteroid, has been shown to be useful and life-prolonging for patients with Duchenne muscular dystrophy, a rare and fatal disease. Its U.S. launch has been delayed, however, after lawmakers questioned the dramatic price hike that came with its debut here.

How much of a price increase? That depends on who you ask. The drug will be marketed under the name Emflaza, and its sticker price will be $89,000 for a year’s worth of pills. The CEO of Marathon Pharmaceuticals, the company marketing the drug, said that the typical cost per patient after discounts and insurance rebates would be $54,000 per year.

The Wall Street Journal reports that families currently pay an average of $1,200 to import deflazacort from countries where it’s available. The price varies: One mother reports paying $800 to $1,000, and other families pay up to $1,600.

Marathon Pharmaceuticals didn’t invent or even perform its own clinical trials on deflazacort, but bought the rights to data from clinical trials performed on Duchenne muscular dystrophy patients in the 1990s, using that to submit an application to the FDA. The clinical trial data showed that the drug helped patients keep more muscle strength, and patients taking it retained their ability to walk for longer.

The company can do this because of the Orphan Drug Act, which gives pharmaceutical companies exclusive patent rights for a few years after developing a new drug or gaining approval for a different use for an existing one. It’s an important program when used as intended, but this isn’t really its intended use.

There are only around 12,000 patients with the disease in this country, and the Washington Post reports that an estimated 7-9% of them even have access deflazacort. In theory, the cost to patients will be close to zero between insurance and discounts, but the high price to insurers is still frustrating.

Lawmakers have even taken up the cause: Sen. Bernie Sanders (VT) and Rep. Elijah Cummings (MD) sent Marathon a letter asking for “detailed information” about the drug’s development, including how much it actually cost Marathon to bring it to market.

Rep. Robert Aderholt of Alabama, the chairman of the committee that funds the FDA, also questioned the drug’s price hike.

“It makes me question whether the current construct of how FDA approves orphan drugs does more harm than good if companies have found a way to game the system,” Aderholt said in a statement yesterday.

Coincidentally, yesterday Marathon announced that it plans to delay the Emflaza launch to discuss the pricing scheme with caregivers and other stakeholders. It was originally supposed to go on the market last month.

Editor's Note: This article originally appeared on Consumerist.