It certainly didn't take long for Schering-Plough (NYSE:SGP) to start reaping rewards from its purchase of Organon BioSciences.

Just seven days after it closed its acquisition, the drugmaker announced that the FDA had accepted a New Drug Application (NDA) for antipsychotic asenapine, which it acquired in the deal that sent Akzo Nobel's (NASDAQ:AKZOY) human- and animal-health-care subsidiary to Schering.

If it's approved next year, asenapine would enter a competitive market for bipolar and schizophrenia treatments, which is probably one of the reasons that Pfizer (NYSE:PFE) discontinued its partnership developing asenapine with Organon.

However, the compound has performed fairly well in clinical trials against future competitors. In one study, asenapine worked as well as Eli Lilly's (NYSE:LLY) Zyprexa in reducing mania symptoms in bipolar patients, and caused weight gain in fewer patients, so it could be favored by patients and doctors. In a head-to-head trial against Johnson & Johnson's (NYSE:JNJ) Risperdal, asenapine reduced schizophrenia symptoms, but again produced less weight gain than the drug already on the market. Finally, a safety trial comparing it to AstraZeneca's (NYSE:AZN) SEROQUEL demonstrated that the drug has minimal if any effect on heart rhythm.

Schering won't know for a while whether the $14 billion purchase was a good deal, but the timing of the NDA filing epitomizes why Schering made the purchase. The Organon acquisition gives Schering five drugs in phase 3 trials and another 16 in earlier stages of the clinic. Add to that about $5 billion in sales -- minus some poultry vaccines that the FTC made it sell off -- and Schering is well on its way to being less dependent on its cholesterol drug partnership with Merck (NYSE:MRK) for future growth.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. Johnson & Johnson and Eli Lilly are selections of the Income Investor newsletter. Pfizer is a pick of the Inside Value newsletter. The Fool has a disclosure policy.