On Monday, branded and generic drug powerhouse Novartis (NYSE:NVS) released financial results that followed a challenging first quarter with its drug development programs.

Novartis experienced setbacks with its diabetes compound, Galvus, and dealt with losing sales from the irritable bowel syndrome treatment Zelnorm. Despite both of these issues, Novartis managed to put together a strong first quarter for its top and bottom lines.

Novartis is in a transformational phase right now while it divests its non-health-care-related businesses and focuses on pharmaceutical sales. Revenue from continuing operations, which exclude comparisons with the divested businesses, were up 18% for the quarter versus a year ago, and earnings rose 11% to $0.92 per share.

Following the prospects of major pharmaceutical giants like Novartis and its billion-dollar drugs can be daunting for investors. For those patient enough to take the time to look into the large-cap pharmaceutical stocks, though, the rewards can be excellent. Especially when shares drop due to setbacks with one drug, investors throw the baby out with the bathwater, and a buying opportunity opens up. After pulling Zelnorm from the market last month, shares were pushed down 6% on the news and gave opportunistic investors the chance to buy shares at a nice discount at the time (the stock is up 7% since then).

The (at least temporary) loss of  much of the revenue from Zelnorm is obviously a negative event for Novartis, and even resulted in it guiding down its sales projections for the year to 5% growth versus 2006. But the pharma is diversified enough that the loss of any one drug won't dent its future financial prospects in the long run.

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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.