Updated from 10:31 am EDT with analyst comment.

Sarepta Therapeutics' (SRPT - Get Report) stock price is lower Thursday on speculation the U.S. Food and Drug Administration might be pressuring the company to provide Duchenne muscular dystrophy patients with at-cost access to eteplirsen on a "compassionate use" basis instead of granting accelerated approval.

The spark for the Sarepta speculation was an FDA announcement Thursday about a new, streamlined way for patients with serious diseases to gain expanded access to experimental drugs that are not yet approved.

Some investors see expanded access to eteplirsen as a compromise solution to the long-delayed FDA review of the Duchenne drug. The FDA could stick to its scientific principles by officially rejecting eteplirsen and requesting more clinical data from Sarepta, while at the same time offering a way for Duchenne patients to be treated with the unapproved drug.

Sarepta would be the financial loser in this scenario. Under FDA rules, the company could charge for expanded access to eteplirsen but only to recover manufacturing costs. Sarepta would also need to raise a lot more money from investors to fund new or ongoing clinical trials of eteplirsen.

It's not clear if this scenario, if it came to fruition, would be financially viable for Sarepta, which is why the stock is down 27% to $15.60 in Thursday trading.

Duchenne patients might not benefit either if they can't afford the high cost of eteplirsen, or if their insurance companies refuse to pay for an unapproved drug. 

Expanded access to eteplirsen with cost recovery would be the "best compromise" for FDA and Sarepta, says RW Baird biotech analyst Brian Skorney, in a note to clients Thursday. "It has the potential to eliminate the company's burn and set the stage for a definitive readout that could lead to class approval. Gentium pursued this option to a favorable outcome. In the short term, shares may sell off further but we think are already undervalued, should this pathway be pursued," Skorney writes.

FDA spokesperson Sandy Walsh says Thursday's announcement about expanded access to experimental drugs had nothing to do with Sarepta or eteplirsen.

"This has been in the works for a long time and is not at all related to any specific drug or any other actions," said Walsh, in response to a question about a possibly link to eteplirsen. "We've been promising release of the final form for quite a while now and are pleased it is ready for physicians to use. We've said often that we were in the final stages of getting this form out."

But that's not stopping investors from connecting the two events. In the absence of a resolution to the FDA's long-delayed review of eteplirsen, speculation is what investors do best.

Adam Feuerstein writes regularly for TheStreet. In keeping with company editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback; click here to send him an email.