Myriad Genetics has reported encouraging Phase II trial results on a drug that it claims tackles the underlying pathology in Alzheimer’s disease.

Flurizan (MPC-7869; R-flurbiprofen) works by reducing levels of beta amyloid, which some believe is the primary cause of neurotoxicity and amyloid plaque development in the brains of AD patients.

Current treatments for the disease, such as Novartis’ Exelon (rivastigmine) and Pfizer/Eisai’s Aricept (donepezil), work by boosting neurotranmitters in the brain, helping neurons work more efficiently but not addressing the underlying loss of nerve cells.

Last November, Myriad presented 12-month data from the study showing that Flurizan was able to improve cognition and memory in patients with mild-to-moderate AD. On Sunday, follow-up data in patients who remained on treatment out to 21 months revealed that these improvements were maintained, and actually showed an improvement in performance over time, something that has not been seen with existing treatments.

"The results are additional evidence that Flurizan appears to be modifying the course of the underlying disease process,” said Adrian Hobden, Myriad’s president. The company has started a Phase III clinical trial of Flurizan in patients with mild AD.

Generic flurbiprofen, a non-steroidal anti-inflammatory drug, is a mixture of R and S molecules whose structures are mirror images of one another. Myriad’s contains only R-flurbiprofen, the form that seems to have the greatest impact on beta amyloid but has little or no anti-inflammatory effect.

Analysts have suggested that a drug that addressed the underlying cause of AD could reach more than $4 billion in sales at peak.

Other companies working on drugs that block the formation of beta amyloid include Canada’s Neurochem, whose Alzhemed (tramiprosate) is in Phase III testing, and Ireland’s Elan with AN-1792 (an antibody partnered with Wyeth) in Phase II.