With profits at its back, one-hit wonder Onyx Pharmaceuticals (NASDAQ:ONXX) is trying to develop its second potential blockbuster the easy way -- by licensing it.

Yesterday, the formerly pipeline-less drugmaker announced its second license in the last few months. In November, it licensed a pre-clinical drug from England's BTG International, and yesterday it licensed two more drugs from privately held S BIO. Both compounds -- one phase 1 and one preclinical -- are JAK2 inhibitors. JAK2 seems to be involved in a wide range of diseases, including cancer and autoimmune diseases, so affecting how that protein works makes a tempting target.

The drugs are behind other JAK2 inhibitors being tested against myelofibrosis, a disease that inhibits bone marrow production of blood cells -- Exelixis' (NASDAQ:EXEL) XL019 and Incyte's (NASDAQ:INCY) INCB18424 -- but not by enough to make much of a difference. The drug with the best results against myelofibrosis will likely become the dominant drug no matter the order in which they finish the marathon race to approval.

My biggest problem with Onyx has always been that, without a pipeline, it was completely reliant on Nexavar for income. I realize that it's not easy developing a second major hit -- just ask fellow class members Elan (NYSE:ELN), Amylin Pharmaceuticals (NASDAQ:AMLN), Abraxis Bioscience (NASDAQ:ABII), and the Buggles. Becoming the next Amgen (NASDAQ:AMGN) (or Beatles) isn't easy, but at least you've got to try. Patents do eventually run out, you know.

I'm not quite ready to jump on the Onyx bandwagon yet, however. With its new pipeline drugs still in the early stages of development, Onyx's near- and even medium-term prospects rely solely on sales of Nexavar. The drug is approaching saturation for treating liver and kidney cancer, so it'll have to get approved for another indication to see sales really take off again. Unfortunately, Nexavar has failed to show an effect in skin and lung cancers, so further growth is far from guaranteed.

While yesterday's developments aren't a reason to run out and buy Onyx, the company is looking better and is certainly worth keeping an eye on.

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Fool contributor Brian Orelli, Ph.D., is glad Right Said Fred didn't have another one in it. He doesn't own shares of any company mentioned in this article. The Fool owns shares of Exelixis. The Fool's disclosure policy is too sexy for this article.