ARIAD Pharmaceuticals (NASDAQ: ARIA) got its leukemia drug ponatinib approved by the Food and Drug Administration today. Shares are down 14% as I write this .

Why? It's tempting to blame it on the new brand name Iclusig. My stomach turns just saying it. I realize a lot of the powerful sounding names -- Novartis' (NVS 1.10%) Afinitor and Dendreon's (NASDAQ: DNDN) Provenge, for instance -- have been taken, but the brand names seem to be getting worse lately.

Alas, I doubt investors care about the name that much. Instead, my guess is this is simply a sell-the-news event. The approval was no surprise. The data was solid. Even an early approval wasn't all that surprising, especially after announcing it wouldn't have to wait for a companion diagnostic to be approved. The company used the FDA's fast track rolling submission to get some of the data in front of FDA reviewers early. And the FDA has been making quick decisions about oncology drugs recently. Approvals for Medivation's (MDVN) Xtandi and Bayer and Onyx Pharmaceuticals' (NASDAQ: ONXX) Stivarga both came in a month or more before the PDUFA date.

With the binary event out of the way, investors have to wait to see how well Iclusig will sell. The drug will be used after Otsuka and Bristol-Myers Squibb's (BMY -0.27%) Sprycel, or Novartis' Tasigna, or by patients with a mutation that doesn't allow them to take those drugs.

Investors could be fretting about the boxed warning on the label, pointing out the potential for blood clots and liver toxicity , but I don't see it as a major issue. The drug is patients' last resort; side effects are a secondary concern when death is inevitable.

At a market cap of $3.3 billion, much of the early sales of the drug are already built into ARIAD's share price. ARIAD's CEO Harvey Berger told Bloomberg that it was targeting annual sales of $600 million to $800 million in the 2017 to 2018 time frame. Assuming a multiple of five times sales, that would value the company at $3 billion to $4 billion.

If ARIAD is going to grow from here, it'll have to do it with its other drugs. Ridaforolimus, which is partnered with Merck (MRK 0.10%), might not be dead yet, despite being turned down by the FDA as a treatment for sarcoma. And ARIA has two other drugs in clinical development.

Success of any of those programs should have the usual effect of sending shares upwards.