On Wednesday, drugmaker Wyeth Pharmaceuticals (NYSE:WYE) announced that the FDA had approved its cancer-fighting compound, Torisel. The approval of Torisel turns up the heat in the kidney cancer targeted-therapy market, as it will compete directly with Onyx's (NASDAQ:ONXX) Nexavar and Pfizer's (NYSE:PFE) Sutent as a treatment for the disease.

How well Torisel will fare against Nexavar and Sutent won't be known until more data on all three compounds comes out and they can be compared against each other. Right now, besides Torisel's differentiated mechanism of action, its efficacy data, aside from its overall survival data, appears slightly worse when compared to the Nexavar and Sutent clinical studies.

For instance, treatment-naive metastatic kidney cancer patients who took Sutent had a median progression-free survival (PFS) of 47 weeks in one of its pivotal studies. This trumps the treatment-naive Torisel-dosed patients in its phase 3 study, who only had five and a half months of PFS. Patients in one of the pivotal Nexavar phase 3 trials had a PFS of 167 days when taking the drug. This sounds similar to the Torisel data, but the Nexavar study patients were tougher to treat since they had already been previously treated with another therapy.

An article of this length can't go into complete detail about all the differences in the three drugs' data packages. The PFS comparison cited above comes with the big caveat that comparing clinical trial results across studies can be fraught with statistical issues. For example, the Sutent control group in its study had a longer PFS than the control patients in the Torisel study, which might mean that the superior Sutent efficacy data is a result of a healthier study population.

Regardless, without any one of the three compounds coming out as the unequivocal efficacy or safety leader yet, there will be room for all three drugs in treating kidney cancer.

Getting Torisel on the market is just the latest in a string of successes for Wyeth with its drug pipeline. While it may not be the cheapest big pharma on the market, Wyeth doesn't have some of the issues facing the other pharmaceutical giants.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. Pfizer is an Inside Value recommendation. The Fool has a disclosure policy.