NEW YORK (CNNMoney.com) - Right now it's an experimental cancer drug about to get a thumbs up from the FDA for some second-string use, but Wall Street is hoping it will grow into a multi-use blockbuster.

Can Bristol-Myers Squibb's Sprycel, neé dasatinib, do it?

"The initial opportunity is very small, but think of the opportunity as an upside-down pyramid," said Jami Rubin, analyst for Morgan Stanley.

On June 2, dasatinib goes before a panel of advisors for the Food and Drug Administration. The advisors will take a stand on whether the drug should be approved as a treatment for a type of bone marrow cancer called chronic myelogenous leukemia, or CML. The full FDA will take this vote into consideration on June 28, the expected deadline for the dasatinib review. Since FDA advisors released documents Thursday saying the drug is effective, chances are good it will get the green light, and a new name: Sprycel.

Analysts' short-term sales projections for the drug are relatively modest, considering that it would only be used by cancer patients who failed CML treatment with Gleevec. That's the top-selling drug for the Swiss drug maker Novartis (up $0.04 to $55.52, Research), totaling $2.2 billion in 2005 sales and costing patients about $40,000 a year. Analysts say this narrows the playing field considerably for Bristol-Myers' (up $0.27 to $24.82, Research) dasatinib, because it would be used as a second-line drug, instead of a first-line.

"We suspect [Bristol-Myers] can't get anything other than Gleevec failures because that's the only thing they tested on," said Les Funtleyder of Miller Tabak. "You can't get a label [from the FDA] for something you didn't test on."

Funtleyder and analysts from Sanford C. Bernstein project $300 million in annual sales for the drug, assuming it gets FDA approval. Barbara Ryan, analyst for Deutsche Bank North America, projects annual sales of $470 million by 2008 and said revenue could keep growing, but that depends on whether Bristol-Myers can get the drug approved for additional treatments.

"[Sales] are going to continue to grow over time, but that's going to be a function of the data and we haven't seen any other indications but this first one they're going after," said Ryan of Deutsche Bank North America. Ryan said she wouldn't provide longer-range sales estimates without more information.

But New York-based Bristol-Myers is studying dasatinib for a wide variety of anti-tumor treatments, including cancer of the intestinal tract, ovaries, pancreas, prostate and breasts. In a recent interview, Bristol spokesman Tony Plohoros called the drug "potentially a pipeline within a [single] product."

Morgan Stanley's Rubin projects that dasatinib annual sales would reach $700 million by 2010, but could grow much larger. Rubin believes doctors will prescribe the drug "off-label" for first-line treatment of CML. This means that doctors would be confident enough to prescribe the drug for that specific type of CML treatment without waiting for FDA approval. If this happens, dasatinib could enjoy Gleevec-like success, said Rubin.

"Sprycel has a broader application than Gleevec, so we think ultimately Sprycel sales could be as big as Gleevec sales are today," said Rubin.

The analysts interviewed for this story do not own shares of the companies mentioned here.

To learn more about potential cancer drug blockbusters and the American Society of Clinical Oncology, click here.

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