What happened

Endo International (NASDAQ:ENDP) was up as much as 13.6% Tuesday before settling down to about half that gain after reporting preliminary third-quarter revenue and earnings results on Monday. The drugmaker can't seem to sustain a rally since Endo's shares did the same thing Monday, shooting up as much as 18% before ending the day up just 1.4%.

So what

Endo said third-quarter revenue came in at about $785 million with a loss of approximately $0.45 per share on a GAAP from continuing operations basis. Looking at adjusted earnings from continuing operations, Endo will post a profit of $0.85 per share.

The company also reaffirmed its revenue guidance for the year of between $3.38 billion and $3.53 billion. Endo's adjusted earnings from continuing operations are expected to be at the upper end of the guidance given in August of $3.35 to $3.65 per share.

Endo also noted that it plans to defend and protect its Vasostrict franchise from competition, pointing to a lawsuit filed against the FDA asking the court to make the agency stop the non-sterile-to-sterile bulk compounding of vasopressin, the active ingredient in Vasostrict. Endo recently got three patents issued for Vasostrict, which bring the total patents to five, all of which expire in 2035.

A virtual graph going up and down.

Image source: Getty Images.

Now what

Investors will have to wait until Nov. 9 to see the full results, but it's clear the third quarter was a solid one for Endo. It's likely that the stock didn't take off because it wasn't a breakout quarter -- management, for example, didn't raise 2017 guidance.

Considering all the struggles that Endo has had this year -- shares are down more than 60% year to date -- it seems reasonable for investors to take a wait-and-see attitude toward the drugmaker, especially with the uncertainty with Vasostrict hanging over its head.