Results from 12 patients isn't enough to get a drug approved, but it's certainly enough to get investors excited about Micromet (Nasdaq: MITI). The biotech jumped as much as 17% today, after the company announced early results for its phase 2 trial testing blinatumomab in acute lymphoblastic leukemia, or ALL.

Nine of the 12 patients who took blinatumomab achieved a complete remission, meaning the leukemia was eradicated. A 75% response rate is pretty impressive, considering that all of the patients had already relapsed after a first round of therapy. Typically, this type of patient would see complete remissions in the 17% to 45% range.

Blinatumomab is designed to stimulate the patient's immune system to attack the cancer. Bristol-Myers Squibb's (NYSE: BMY) Yervoy and Dendreon's (Nasdaq: DNDN) Provenge use similar strategies, albeit through entirely different mechanisms.

The same molecule -- CD19 -- that the immune system homes in on is also present in non-Hodgkin's lymphoma, which blinatumomab is also in clinical trials for. The early success in ALL should give investors hope that it may work for that type of blood cancer as well.

The big loser in blinatumomab's success is AstraZeneca (NYSE: AZN). The pharmaceutical giant licensed the drug from Micromet but handed back the North American rights to the drug a few years ago.

Micromet can't say "I told you so" to AstraZeneca just yet, though. It'll need to run a larger trial to prove that the early results weren't just a fluke. The good news is that blinatumomab is so successful that it should be able to get on the market even if the data isn't quite as good as the early results.

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Fool contributor Brian Orelli holds no position in any company mentioned. See his holdings and a short bio. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.