While most of its biotechnology peers floundered in 2016, Cinderella stock Exelixis (NASDAQ:EXEL) has treated investors to a stunning 200% gain so far this year. Its lead drug, Cabometyx, also branded as Cometriq, spent years generating lackluster sales as a rare thyroid cancer treatment. Many never imagined it would dance at the big ball after it flopped in a big prostate cancer trial years ago.

Bibbidi-bobbidi-boo! An approval for kidney cancer on the back of stellar data gave Exelixis a nearly magical market makeover, but competition with a rising star from Bristol-Myers Squibb (NYSE:BMY) remains a concern.

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There's a chance Exelixis can expand Cabometyx's addressable patient population before too long, which would give the stock more room to run. Let's take a closer look to see if this biotech stock can continue dancing long after the clock strikes midnight into the New Year and beyond.

First to score a trifecta

In April, the FDA approved Cabometyx for advanced kidney cancer patients who progressed following treatment with drugs that starve tumors of their blood supply. It ran head-on into one of the most successful new cancer therapies in a generation -- Opdivo, from Bristol-Myers Squibb, which earned FDA approval to treat the same patients last November.

Cabometyx and Opdivo weren't tested head-to-head against each other, but both were pitted against the standard chemo drug generally used to treat this population. Compared with Afinitor, both showed comparable benefits in terms of tumor reduction and overall survival.

Exelixis, though, was able to boast that Cabometyx was the first to significantly improve the third standard efficacy measurement. The majority of patients receiving Exelixis' therapy survived without signs of disease worsening about 95% longer than those receiving the standard of care.

More encouraging figures

While many analysts didn't think Cabometyx could gain much traction in the somewhat limited advanced kidney cancer indication with Bristol's drug already becoming entrenched, sales figures suggest otherwise. In the third quarter, Exelixis' revenue came in about $17 million higher than Wall Street expectations at $62.2 million, a 531% rise over the same period last year.

Cabometyx is in a study that could expand its label to include newly diagnosed patients with advanced renal cell carcinoma, instead of those with disease progression following an initial treatment. In a mid-stage study against another kinase inhibitor, Sutent from Pfizer, patients receiving Cabometyx enjoyed a 31% reduction in the rate of disease progression or death.

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Moving up to the front of the kidney cancer line would probably push annual Cabometyx sales well past the $1 billion mark. Another expansion to liver cancer might push its sales higher still. Exelixis is running a late-stage study that could support an approval for treatment of hepatocellular carcinoma if successful. Earlier this year, independent data monitors allowed the study to continue, and we should know more when the company announces data from the study, probably early in the new year.

While there's a solid chance Exelixis stock can continue its upward climb, it could also stumble. Label expansions to front-line kidney cancer and liver cancer are far from certain, and so is the revenue from these indications that its market cap of around $4.8 billion at recent prices seems to have priced in.

The stock could swoon if the market gets the slightest hint that yearly revenue might not reach $1 billion in the years ahead. Third-quarter figures came in at an annualized run rate of just $248.8 million, which gives it a long way to drop if the company hits a patch of bad luck in the clinic.