Researchers took the center stage at an Alzheimer's conference in Monaco to offer late-stage biomarker evidence to support Eli Lilly's optimism about the efficacy of its controversial drug solanezumab. In the two pivotal Phase III studies of the drug, investigators determined that there was a noticeable effect on the level of beta amyloid found in patients' blood, suggesting that solanezumab had reduced levels of the toxic protein in the brain.
Eli Lilly ($LLY) insisted in the wake of the Phase III program that a secondary analysis of one trial detected a significant improvement in cognition among patients with a mild form of the disease. The efficacy readout for that one group--patients with moderate cases of the disease were left unaffected and the studies failed both primary endpoints--could not be confirmed in the second trial when investigators established improvements in cognition of mildly afflicted patients as an endpoint. But Lilly has enjoyed a big boost in its stock price after touting signs of efficacy seen in pooled data.
"The beta amyloid biomarker results in the trial support the small, yet significant cognitive benefit, especially for the Alzheimer's disease patients," said Rachelle Doody, an investigator at Baylor, in a prepared statement. "We think that the benefit is related to the removal of soluble amyloid from the brain and into the blood."
Once again, though, Lilly will have something far short of compelling data on solanezumab.
Biomarkers and pooled data may help support further studies of the drug, as well as other programs that rest on the beta amyloid hypothesis, but they don't prove that solanezumab works as hoped. Nevertheless, the first sign of success in this field has fueled tremendous enthusiasm that something in the pipeline could eventually work--perhaps even pushing regulators to approve new therapies with something less than clear efficacy data. And any newly approved drug would find a massive market of millions of desperate patients.
A number of new studies are moving out of mild-to-moderate cases as investigators grow increasingly convinced that existing therapies will not be able to reverse brain damage once it has occurred. Now the beta amyloid theory is more focused on the notion that preventing buildups in at-risk populations may be the best therapeutic approach.
"The findings are cause for cautious optimism in the drive to develop and design of future AD trials," said Michael Weiner, the principal investigator in the Alzheimer's Disease Neuroimaging Initiative study. "It shows that research like solanezumab bolsters the need for large biomarker trials like ADNI to move as quickly as possible to the earliest identifiable stages of the disease."
- here's the press release
- get the Reuters story
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