Dollar-a-dose, off-patent drug being marketed in the US for $89,000 as a muscular dystrophy treatment

Deflazacort, a steroid, can be purchased online from non-US sources for $1.00, but now it's being marketed by Illinois's Marathon Pharmaceuticals for $89,000 as Emflaza, to treat Duchenne muscular dystrophy, which predominantly affects men in their 20s.

The drug's never been approved in the US, and Marathon has a special dispensation to market it for the rare disease, so it gets to name its price.

In many ways, Marathon is taking a page from Shkreli's playbook. By bringing a drug that's been well-established as safe in other markets to the U.S. for the first time in order to treat a rare disease, the company doesn't just control its pricing destiny — it will also receive a coveted "priority review voucher" which it can hawk to another firm for tens (or even hundreds) of millions of dollars. If not, the company can use it to expedite a future drug approval in order to gain a first-to-market advantage.

In fact, one of Marathon's clinical trials that the FDA used as part of its decision-making process was conducted more than 20 years ago, saving the firm plenty of study costs.

Duchenne drugs have fostered recent controversy in the U.S. Last year, the FDA approved a pioneering Duchenne treatment from Sarepta Therapeutics (SRPT, -5.15%) over the protests of its own scientific advisers who said it lacked proven efficacy. Unlike Sarepta, Marathon's product doesn't actually address the protein deficiency at the heart of the disease, but rather has shown promise in improving muscle strength.

This Pharma Company Is Selling a Decades-old Drug to Treat Muscular Dystrophy for $89,000
[Sy Mukherjee/Fortune]