Here's who has the most to lose if the government starts negotiating drug prices (IBB)

Reuters/Jonathan Ernst

The GOP's Obamacare replacement plan got pulled from a vote in the House on Friday, and healthcare stocks have been rallying ever since. 

But when it comes to drug pricing, pharmaceutical companies might not be out of the woods yet.

The American Health Care Act, the bill proposed by Republicans to replace the Affordable Care Act notably did not bring up prescription drug prices.

Still, President Donald Trump has repeatedly brought up the possibility of there being a national bidding process for drugs.

"Drug stocks have been held down by fears of US government action and it is kind of tempting to call the all-clear on drug legislation as the president may move on after the recent AHCA failure," Bernstein analyst Ronny Gal wrote in a note Monday. "However, earlier last week, Trump explicitly discussed national bidding process suggesting (to us, at least) that some sort of bill was close to completion." 

Trump has been speaking about drug prices since December, specifically addressing the rising costs of prescription drugs that consumers have been facing in the last few years.

In March, Trump tweeted that he's working on "a new system where there will be competition in the drug industry."

Later that week, the president met with Reps. Elijah Cummings and Peter Welch, along with Johns Hopkins president Dr. Redonda Miller, to talk about drug pricing, where the representatives showed Trump a bill that would allow Medicare to negotiate lower drug prices. The government currently can't negotiate prices for drugs that are part of Medicare's Part D program, which covers most prescription drugs. 

Trump weighed in again last week, saying "we’re going to bring it down, we’re going to have a great competitive bidding process" in a speech on March 20.

"Medicine prices will becoming way down, way way way down," he said. "And that’s going to happen fast."

As a whole, Medicare Part D accounts for 30% of biotech companies' gross sales, 25% of large pharma companies' gross sales, and 20% of specialty pharma gross sales, according to Bloomberg Intelligence. 

Among specialty pharmaceutical companies (often defined as companies with expensive medications for rare or chronic conditions), here's who's the most exposed to potential Medicare Part D negotiations, from most to least, according to the Bloomberg report.

• Allergan, 39% of gross sales in 2015. That's in large part because of Namenda, a drug used to treat moderate to severe Alzheimer's. 
• Mallinckrodt, 28% of gross sales in 2015. Bloomberg Intelligence pinned that exposure on H.P. Acthar, a drug used to treat multiple sclerosis, that was one of the top 20 expenses of the Part D program. 
• Valeant, 13% of gross sales in 2015. The exposure risk was among the lowest, but Bloomberg Intelligence noted that with regard to possible Part D negotiations, "the company can't afford to suffer even minor setbacks if it's to meet covenants and debt obligations."
• Shire, 12% of gross sales in 2015. Shire had the least Medicare Part D exposure of specialty pharmaceutical companies.

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