What: Shares of POZEN (NASDAQ: POZN), a pharmaceutical company with a focus on products that treat acute and chronic pain, treated investors to a soothing gain of more than 10% in the month of July.

So what: Investors appear be growing more bullish on the company's future as they've had more time to analyze Pozen's pending $146 million acquisition of Tribute Pharmaceuticals Canada. After the transaction is finalized, Pozen and Tribute will officially become wholly owned subsidiaries of the newly formed Aralez Pharmaceuticals Limited and will be headquartered in Ireland. 

Management is touting several reasons for investors to be bullish about the acquisition, which include having a broadly diversified product line, greater access to capital to fund future growth, and a tax advantaged status that comes from moving the company to Ireland. Ireland currently has a much lower corporate tax rate than the U.S. and thus could save the company a substantial amount of money in the future.

Looking beyond the pending acquisition, investors appear to be growing more confident in Pozen's drug Yosprala, its delayed-release aspirin used to prevent heart attacks and reduce gastric-related problems, which is currently pending FDA approval. Peak sales estimates for the drug are currently hovering around $300 million in the U.S. alone, which is a huge number compared to Pozen's 2014 total sales of $32 million. With management currently guiding for a 2016 approval and launch, it's no wonder that investors are bidding up Pozen's stock. 

Now What: While Pozen certainly appears to have a lot going for it, I think there are reasons for investors to approach this stock with caution. 

Huge acquisitions tend to come with huge execution and integration risks, and many fail to live up to their full potential. While the tax savings of this deal alone appear to make the acquisition worthwhile, it's still a risk that investors need to keep in mind.

In addition, while Yosprala appears to hold a great deal of promise, it also comes with quite a spotty history. Pozen has already received two separate warning letters from the FDA related to a Yosprala third party manufacturing supplier that has delayed its launch, and its original collaborating partner Sanofi terminated its agreement with Pozen after only being in place for slightly longer than a year. While it's certainly possible that the challenges related to Yosprala are behind the company, it doesn't make me willing to put my money behind giving management the benefit of the doubt.

Still, as Pozen currently sports a market cap around $320 million, if it can realize the benefits of its merger and successfully launch Yosprala, then shares could certainly become a multi-bagger for investors from here.  Personally, I'm content to watch from this story unfold from the sidelines for a few more quarters of data before I'd be willing to call the shares a buy.