Earlier this week, drug developer Neurochem (NASDAQ:NRMX) released some more hints as to what sort of data investors could expect from the company's just-finished phase 3 study for its potential Alzheimer's treatment, Alzhemed.

In April, Neurochem announced that it would take another couple of weeks for the data from its Alzhemed clinical trial to be finalized, since the company needed to find "an accurate statistical model that appropriately describes the data and provides accurate results."

At an Alzheimer's disease medical conference this week, the lead author for the drug's phase 3 trial added that the data produced in the 1,052-person study varied significantly and unexpectedly between the study's different testing centers. This was cited as the cause for the delay in releasing the clinical trial results.

Neurochem also announced in a press release that preliminary data showed Alzhemed faring positively on the study's primary endpoints, which are cognitive tests and an MRI scan. This sounds highly positive for Alzhemed. However, before investors get their hopes up for the results, they should consider that Neurochem also states that it can't ascribe any sort of weight to this preliminary data because of the continued revision of the study's statistical model.

The FDA doesn't like data that is hard to interpret, nor is it a fan of retrospective analyses. In Neurochem's favor, the FDA knows that it is extremely difficult and complex to run a clinical trial in Alzheimer's disease. It also knows that there are few treatment options out there for the estimated 27 million sufferers worldwide. Nonetheless, with so little clinical data released on the use of Alzhemed in humans, not to mention the data-juggling Neurochem is doing, investors are gambling on a drug that is likely to produce controversial study results.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.