Watch out, Allergan. Activist investor David Tepper won approval to push a shake-up

Allergan probably won't win FDA approval for a new uterine fibroids drug, analysts say, and it's facing new competition for its top-selling drug Botox. (Allergan)

Allergan has plenty of problems on its hands, what with an intense battle over blockbuster Restasis patents, a stock that stubbornly refuses to bounce back to previous levels and investor pressure for sales or spinoffs.

Now it has another one.

Activist investor David Tepper won a Federal Trade Commission approval on Thursday that would allow him to agitate for change at Allergan, Wells Fargo analyst David Maris reported in a note to investors. Tepper’s Appaloosa Management and Palomino Fund snagged the approval after Appaloosa boosted its Allergan holdings to 3.7 million shares to become the company’s 15th largest investor, Maris said.

Allergan didn’t have much to say about Tepper’s potential—or actual—demands, Maris said.

“When asked whether Appaloosa had reached out with specific changes they would like to see, Allergan indicated that it would not discuss any specific discussions they have had with any shareholders or even confirm they have had discussions with any particular shareholders,” the analyst wrote.

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The company recently launched a strategic review that could lead to asset sales, with “all strategic options” on the table, RBC Capital Analysts’ Randall Stanicky reported last month.

"Allergan underscored it has a ‘bias for action’ which we thought was a notable comment,” Stanicky wrote at the time.

Reports since then say Allergan is zeroing in on its women’s health unit as a prospect for unloading. Analysts have said that business could bring in $5 billion in a sale.

Stanicky has been calling on Allergan since November to unload some assets, flagging women’s health as an attractive option. At the time, Stanicky figured the unit could bring in $6 billion, but Allergan has since run into trouble with Esmya, a uterine fibroids drug up for approval at the FDA.

RELATED: Allergan could sell women's health for $6B, if it would only agree to split: analyst

That trouble ratcheted up Friday when European regulators rolled out new restrictions on the drug's use. The European Medicines Agency said women with liver problems shouldn’t use it. Other patients should be monitored for new liver problems, the agency said, and the patients should only use Esmya for more than one treatment course if they’re not eligible for surgery.

The FDA had already delayed its Esmya decision, and now, the agency “is unlikely to approve the drug, in our view,” Bernstein analyst Ronny Gal said in a Friday note. "Even if it does, the market value is negligible. We already had the drug out of our model, this view is confirmed here.”

RELATED: Look out, Allergan: Doctor surveys show the 'Botox competitive threat is real'

Meanwhile, on Wednesday, retail pharmacies added to Allergan's Restasis mess by suing the company for antitrust violations, saying it had used sham patents to extend its monopoly and delay generic versions of the eye drug since 2014.

What Tepper’s own ideas are—and whether he’ll exercise his option to push them—remains to be seen. But his potential involvement had investors bidding up shares Thursday after the news hit. They moved up 3.7% to $16.23 at closing.