Dimebon - Top Ten Phase III Failures

The drug: Dimebon
The disease: Alzheimer's
The company: Medivation partnered with Pfizer

Talk about de-risked.

Dimebon had everything going for it as it entered its Phase III trial for Alzheimer's disease. The bar for success was set low. With patients facing some critical unmet needs, the therapy only needed to demonstrate modest benefits to win an approval. Some analysts believed that even if Phase III wound up far behind the Russian trial that stirred excitement in the drug, Medivation and Pfizer would be well fixed to gin blockbuster revenue from the product. And Medivation could look to 10 years of actual use in Russia as an allergy treatment for solid evidence that the medication is safe.

Pfizer knew the score when it paid a whopping $225 million upfront to gain the license on the drug. And it offered a half billion dollars more in milestones. Alas, when researchers turned in the final data set, Dimebon looked no better than a sugar pill. A very, very expensive sugar pill.

Researchers are currently enrolling patients for two more late-stage trials of Dimebon for Alzheimer's and Huntington's disease. But investors have been hurt badly. After the Alzheimer's trial came in with disastrous results, the company's share price cratered and has yet to recover from the drubbing it received. Failure at Phase III is always punished severely.

Dimebon - Top Ten Phase III Failures
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