Onyx Pharmaceuticals (Nasdaq: ONXX) and Bayer won the battle, but lost the war. Fortunately for the companies, there are wars on cancer all over the place and the aforementioned battle might be a sign that their cancer drug, Nexavar, will win the next one.

The duo announced yesterday that Nexavar, when added to a chemotherapy regimen of Eli Lilly's (NYSE: LLY) Gemzar and a generic called cisplatin, was unable to extend overall survival compared to Gemzar and cisplatin alone in first-line lung cancer patients.

Interestingly, the triple-drug combo delayed growth of the tumors compared to the chemotherapy alone. Good news, but not enough to get Nexavar expanded into lung cancer; patient survival trumps effects on tumor growth any day.

While the drug didn't help newly diagnosed lung cancer patients live longer, the effect on tumors is a good sign as the companies have already started a phase 3 trial testing Nexavar in later-stage lung cancer patients who have failed other treatments. Nexavar is being tested by itself, which might be the only way for the drug to increase overall survival. The clinical trials supporting its approval in both liver and kidney cancer both tested the drug as a monotherapy.

While yesterday's data should provide a little hope that Nexavar might be able to expand into lung cancer, investors should be careful factoring in potential sales for late-stage patients. Lung cancer is a tough disease to crack. I can't think of any drugs that have shown an effect on lung cancer recently except Pfizer's (NYSE: PFE) crizotinib, which treats a subset of lung cancer patients, and Abraxis Bioscience's (Nasdaq: ABII) Abraxane, a beefed-up version of Bristol-Myers Squibb's (NYSE: BMY) Taxol, which is already approved for lung cancer.

Fortunately, even if Nexavar fails in lung cancer all together, there's plenty of money to be made fighting wars against other cancer types.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. Pfizer is a recommendation of the Inside Value newsletter. The Fool has a disclosure policy.