Ah, the irony. Just hours after Dendreon (Nasdaq: DNDN) released a disappointing quarterly update on its prostate cancer vaccine Provenge, small biotech Medivation (Nasdaq: MDVN) showed the market how it's done .

How? By announcing the late-stage trial results for its prostate cancer drug candidate MDV3100. And they rock. Patients lived on average five months longer taking the oral medication than the placebo, and side effects were reportedly mild.

MDV3100 looks to be a blockbuster in the making. With roughly one out of six men expected to be diagnosed with prostate cancer in their lifetimes, there are plenty of patients to go around. But biotechs with their own candidates -- Exelixis' (Nasdaq: EXEL) cabozantinib comes to mind -- need to be watching what happens here carefully.

And Dendreon really needs to watch its backside here. Provenge is a first-line treatment, but it's having a hard time gaining traction with doctors. Management claims real progress in educating about the Medicare reimbursement for the $90,000 treatment, but knowledge doesn't equal sales. And it may not stop doctors from prescribing MDV3100 off label. If there have been light concerns over Johnson & Johnson's (NYSE: JNJ) Zytiga and its encroachment on Provenge's turf, then Dendreon investors are furrowing their brows harder tonight.

For Medivation investors looking for more possible share-pops, the findings of another trial named PREVAIL -- in which MDV3100 is tested in men who have not yet received therapy -- is expected soon, not to mention an important meeting with the FDA next year.