Anti-amyloid hopeful Bapineuzumab returns to the Alzheimer’s discussion with a Tau twist. Although this drug failed market expectations last year with study results either inconclusive or disappointing, it is still seen as a potential cure and researchers are looking forward to the Phase III studies of the drug set to be out in 2012.
Bapineuzumab’s effects on amyloids and tau give hope to scientists
The latest research studies presented at the Alzheimer’s Association conference show a couple of the trends shaping Alzheimer’s Research today. Firstly, the conversations still surround the anti-amyloid model of curing the disease. No matter what contradictions appear, amyloid plaques are still the “elephant in the room” symptom of the disease, especially in advanced stages when the effects of Alzheimer’s reach visible levels. As a result of this, we cannot discount studies on anti-amyloids (Bapineuzumab falls in this arena). Secondly, researchers are looking towards biomarkers as a way to uncover the underlying mechanisms of the disease. This would not only help them formulate new studies but could also help them validate the anti-amyloid model assumed in their research (see a detailed account of this on the IN VIVO blog).
In July of 2009, Elan and Wyeth reported results from its Bapineuzumab Phase II trial involving a small population of 240 patients. The phase II studies were targeted towards measuring the efficacy of the drug in these patients, a move made to accelerate its entry into the market. However the drug failed to meet its intended end points in this trial. Researchers had to eliminate patients who had the Apo-E4 allele (the ones most susceptible to Alzheimer’s disease) since these patients experienced vasogenic edema in the brain. The remaining patients showed some positive signs, but these were not the intended end points targeted by the studies. The “positive outcomes” from these studies were obtained through post-hoc analysis and was not well received by the scientific community.
Preliminary results provide hope, but are not expected to save any lives
New preliminary results from some ongoing studies show that Bapineuzumab treatment seems to correlate with a reduction in the amount of tau protein found in the CSF of Alzheimer’s patients. Tau protein in CSF is a marker for the loss of active brain cells in patients with Alzheimer’s Disease. Bapineuzumab by itself does not target tau, so these results suggest that it is somehow affecting the system of tau’s generation.
We will need to wait for final results of this study before we start on any new path. Also, these findings (including the post-hoc analysis done on past bapineuzumab studies) will not earn the drug its FDA approval. Consequently, all of this speculation might be considered “day dreaming”. Even though preliminary results look good, all of this speculation could affect pharma stock but not save any lives.
