Eli Lilly Experimental Alzheimer's Drugs Fail Clinical Trials
Eli Lilly’s experimental Alzheimer’s drugs bapineuzumab and solanezumab have failed their clinical trials. The results of the trials proved that the drugs were ineffective at helping patients with mild to moderate dementia.
Bapineuzumab and solanezumab were intended to help patients with Alzheimer’s disease by removing amyloid beta protein plaques usually observed to clog neurons in patients affected by the disease. Both drugs were unable to improve patient thinking and problem-solving abilities.
Dr. Steven Salloway, lead researcher of the bapineuzumab study, said, “We were disappointed there was no clear clinical benefit… I know the consensus from the field is that amyloid plays an important role early in the disease process, so the earlier we can treat it the better the benefit.” Dr. Salloway is a professor of neurology and psychiatry at the Warren Alpert Medical School of Brown University.
Bapineuzumab is a humanized form of murine monoclonal antibody 3D6 made by Pfizer. As a passive immunotherapy approach, bapineuzumab targets the N-terminal region of Aβ to clear excess amyloid beta protein. Over 2,200 patients participated in bapineuzumab trials. While the drug appeared to reduce amyloid buildup, it did not have any effect on patient ability to perform activities of daily life.
Solanezumab is a humanized monoclonal IgG antibody targeting the mid-domain of the Aβ peptide. Its therapeutic rational is to exert possible benefits by isolating and removing small soluble pieces of amyloid beta proteins which are directly toxic to neuron synaptic functions. In the studies, amyloid continued to increase in patients treated with solanezumab and experienced no improvement in thinking abilities.
“We're hoping the use of these medicines earlier on will have more benefit. This will involve a little more creativity in drug development. Companies will have to cooperate and share data… We also need to have drugs that will lower amyloid more dramatically than they did in this trial," Dr. Salloway said.
Alzheimer’s Association Director of Medical and Scientific Operations Heather Snyder said, “It's really important to continue to research a number of different mechanisms that could explain Alzheimer's… We can understand more about how the immune system is involved, for example. It's important to understand what is happening during Alzheimer's."
Pfizer will not pursue further research for bapineuzumab while Eli Lilly plans to conduct another trial for solanezumab.