(Click for video linked to a searchable transcript of this Mad Money segment)

If you're willing to speculate, Cramer wants you to know about the company behind this potential breakthrough cancer drug.

"I'm talking about Pharmacyclics," said Cramer, the maker of ." "Currently the drug is being studied as a treatment for different types of blood cancers including chronic lymphocytic leukemia, mantle cell lymphoma, and multiple myeloma."

Results are quite promising. The clinical trial data for Ibrutinib has been very strong.

In fact results are so strong, "The Food and Drug Administration already considers —that's the designation the FDA gives to drug candidates that it feels are transformational. And Ibrutinib has received this breakthrough drug designation three times over," Cramer said.

"If approved, Pharmacyclics plans to charge $125,000 a year for Ibrutinib, which sounds exorbitant but is actually pretty standard for these . Based on that pricing, the analysts who just initiated coverage on Pharmacyclics at JP Morgan think this drug can do $6.5 billion in peak sales as a treatment for chronic lymphocytic leukemia and mantle cell lymphoma," Cramer said.

Under the terms of an agreement, sales of the drug are split equally with Johnson & Johnson, leaving Pharmacyclics with $3.25 billion per year.

Now, the promise of the drug has not gone unnoticed on Wall Street. Already, shares have rallied 125% ytd and 1,577% over the last 3 years."

Typically Cramer would not advocate chasing a stock with those kinds of gains. However, this time, he's making an exception.

That's because the company is looking at Ibrutinib as treatments for other blood cancers, and JP Morgan only estimated peak sales for the two applications that are furthest along.

Looking at more indications, analysts at William Blair figure that Pharmacyclics could have a $9.2 billion drug on their hands.

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And Cramer sees other reasons to like this stock.
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"Pharmacyclics has a healthy pipeline of other drugs, including a pancreatic cancer drug in phase 2 development, a drug for lymphoma and solid tumors that's also in phase two, and a couple of preclinical programs that might eventually amount to something years and years from now," Cramer said.

All told, the Mad Money host sees every reason for the stock to rally further.

However, as in the case with all investments that are largely a bet on the success of a drug, Cramer reminds the play is a spec. "It's always possible somebody else will invent a better mousetrap," Cramer said.

Therefore, Cramer would play this one with options. "I would buy deep in the money call options to get maximum upside while still being stopped out on the downside."

Call Cramer: 1-800-743-CNBC

Questions for Cramer? madmoney@cnbc.com

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