Congress is going after another drugmaker for pricing a decades-old drug at $89,000

Congress has some questions about the price a decades-old drug that just got approved in the US to treat a rare disease.

Senator Bernie Sanders and Rep. Elijah Cummings have sent a letter to the CEO of Marathon Pharmaceuticals, addressing the high list price of Emflaza (known generically as deflazacort), a drug that was first approved in the US on February 9.

The drug was just approved in the US last week to treat Duchenne muscular dystrophy, a rare disorder affecting mostly boys in which the body's muscles degenerate at an early age. The drug, a kind of steroid, is just the second to be approved for the condition.

But almost immediately, the conversation switched to the list price of the drug, which is $89,000 for a years' supply.

Marathon has said that the intended net price for the drug after rebates and discounts will be $54,000 a year. That's still much more than the $1,200 a year price of the medicine in other countries, where the drug has been around for a few decades.

"We believe Marathon is abusing our nation's "orphan drug" program, which grants companies seven years of market exclusivity to encourage research into new treatments for rare diseases - not to provide companies like Marathon with lucrative market exclusivity rights for drugs that have been available for decades," Sanders and Cummings wrote. The two also encouraged the company to decrease the list price before the drug goes on the market officially in March.

Marathon did not immediately return a request for comment on the letter.

This isn't the first time the duo have asked about drug prices. The two have been calling out everything from expensive cancer drugs to price hikes on old medications. It's also not the first time the two have written to Marathon. The closely-held company once owned Nitropress and Isuprel, two heart drugs that have been criticized for their dramatic price increases.

The move is reminiscent of a plan former pharma CEO Martin Shkreli had with a treatment for another rare disease.

While CEO of KaloBios, Shkreli had told investors that he planned to price a drug called benznidazole that's used to treat the neglected parasitic infection Chagas disease somewhere in the $60,000-to-$100,000 per-treatment range. The decades-old drug hasn't been approved in the US, but it's used around the world and provided in specific instances to the US for free.

Shkreli, in a website set up in January, said that he "literally learned" the price increase move from Marathon.

Marathon will also get a priority review voucher, which are granted to companies which develop treatments for rare diseases as a way to add incentives on drugs that otherwise wouldn't have much commercial value.

The voucher can then be used by the company to speed up its review time for another drug, or it can be sold to another company that wants to fast-track its drug by a few months. These vouchers have been sold for up to $350 million. Sanders and Cummings had questions about that as well, as part of their overarching question to figure out how much Marathon stands to make from Emflaza's approval.

Marathon now has until February 27 to respond to the congressmen's questions.