Last week, pharmaceutical giant Bristol-Myers Squibb (NYSE:BMY) released first-quarter financial results that showed its top line finally starting to recover after falling under attack from a generic drug glut on its top compound, Plavix.

In contrast to the third and fourth quarters of last year, which saw sales dip 13% and 16% respectively, sales for the first quarter only dropped 4% at Bristol-Myers. This moderation in its top-line deterioration occurred as a result of a decline in the volume of generic Plavix on the market, which caused Plavix sales to fall only 5% this quarter.

Partly because of a favorable tax situation, earnings per share declined only $0.01 year over year to $0.35 for the quarter. As a result of this unexpected benefit, Bristol-Myers raised its full-year GAAP earnings $0.12 on each end to $1.24 to $1.34 per share.

Even though Plavix sales are finally beginning to stabilize after Apotex's generic assault on the drug, Bristol-Myers and marketing partner Sanofi-Aventis (NYSE:SNY) are not out of the woods yet. A court decision on the validity of the drug's patents will be coming in the near future, since the trial portion of the patent litigation case against Apotex just concluded two and a half months ago.

With more than a fifth of its revenue at stake with the Plavix court decision, any bet on shares of Bristol-Myers at this time is a gamble hoping for a positive outcome against Apotex with the litigation. Based on how Bristol-Myers and marketing partner Sanofi have fared with other pieces of litigation and patent cases for their top compounds, that's a bet I wouldn't make at this time.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.