September 03, 2025
New data from the full 32-week open-label extension phase of the RewinD-LB trial continue to suggest that the study drug, neflamapimod, may slow cognitive decline in dementia with Lewy bodies (DLB). In addition, lab tests performed during the study suggest that the drug may work by slowing underlying degeneration of brain cells.
What was the RewinD-LB trial?
RewinD-LB was a Phase 2b trial of the experimental drug neflamapimod in people with DLB. A prior Phase 2a trial showed benefit on cognitive decline, particularly for people without evidence of co-existing Alzheimer’s disease (AD). The RewinD-LB trial sought to replicate the findings of the earlier trial, but focused only on people with DLB and no evidence of AD.
In the main phase of RewinD-LB, researchers did not find the same kinds of positive results as they did in the original trial. However, the researchers learned that the drug capsules used in the main phase of the trial were not delivering the same level of drug as they did in the prior Phase 2a trial, possibly explaining the discrepancy in findings.
After the main phase of RewinD-LB, all participants were offered a chance to take the study drug in a phase of the trial called an open-label extension. In the extension phase, all volunteers take active drug; there is no placebo group. The open-label extension lasted for 32 full weeks, and results from the halfway point were previously reported. The researchers have now presented data from the full 32 weeks at the Alzheimer’s Association International Conference, a major medical conference dedicated to dementia research and treatment.
What have researchers learned from the extension phase?
During the extension phase, some volunteers took the same capsules as used in the main phase. These are the “old” capsules. Other volunteers took new capsules that delivered the expected amount of the study drug – “new” capsules.
Measures of cognition and day-to-day function were repeated at the 16-week time point and at the 32-week time point. Volunteers who were taking the “old” capsules continued to worsen. But for volunteers taking the “new” capsules, the worsening was markedly slowed, suggesting that the study drug is effective at slowing cognitive and functional decline when delivered at the intended dose level.
In addition, the study team measured the levels of an important protein in the brain called glial fibrillary acidic protein, which is often considered an indicator that brain cells are undergoing degeneration. In volunteers taking the new capsules, GFAP levels fell during the extension phase, suggesting that treatment with the study drug may slow decline by reducing degeneration of brain cells.
What is next for this neflamapimod as a potential treatment for DLB?
While these results look promising, they are from a Phase 2 trial. The drug will need to be tested in larger, Phase 3 clinical trials before it can be considered for approval.
How can I get involved?
Finding safe and effective treatments for Lewy body dementia takes research, and research takes people like you.
For more information on clinical trials and other studies that might be right for you, LBDA encourages you to visit our clinical trials page. To stay up-to-date on new studies when they launch, you can also sign up for LBDA’s Lewy Trial Tracker.