The company said that the trial failed to show a statistically significant reduction in the levels of beta-amyloid plaques in some Alzheimer patients. There was an overall reduction in the levels, but “the results were confounded by an atypical reduction of levels” in the placebo group as well.
Prana noted that the drug, called PBT2, was shown to be safe and very well tolerated over the 52 weeks of the study. The company said that 40 of the 42 patients involved in the trial completed the full 52-week treatment period.
Prana said that the “suggestion of beneficial effect” from this and earlier trial for patients with Huntington’s disease is “intriguing,” and that the firm is consulting with experts to determine how best to proceed with further study on PBT2’s effect on Alzheimer patients. The company plans to begin a confirmatory study on the drug for Huntington’s and, based on previous discussions with the U.S. Food and Drug Administration, PBT2 for Alzheimer patients supports future clinical development and, ultimately, a New Drug Application in Huntington’s disease.
The stock was down 67% in premarket trading Monday, at $3.25 in a 52-week range of $2.12 to $13.29.