Extension trial demonstrates long-term benefit for Lilly Alzheimer’s drug

New long-term clinical data from Eli Lilly and Company show that Kisunla (donanemab-azbt) provided sustained benefit in early Alzheimer’s over a three-year period.

In the extension study of the Phase III TRAILBLAZER-ALZ 2 trial, the antibody drug slowed cognitive decline in individuals with the condition.

Key preliminary data from the long-term extension study of Eli Lilly’s Kisunla 

Participants who were given Kisunla earlier, attained a 27 percent reduction in their risk of progression to the next stage of disease. This was compared to individuals treated later. However, this data, shared at the 2025 Alzheimer’s Association International Conference (AAIC), found that participants still benefited when they began treatment later on.

Moreover, the drug’s benefit continued to grow over three years, compared to participants in the matched untreated external cohort from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) group.

Additionally, the three-year data showed:

• Over 75 percent of study participants attained amyloid clearance within 76 weeks of starting Kisunla
• In participants who completed treatment with Kisunla, amyloid plaque reaccumulation remained slow, according to observed data after up to 2.5 years.

“The TRAILBLAZER-ALZ 2 long-term extension reaffirms that Kisunla delivered sustained clinical benefit that continued to increase over three years and a consistent safety profile,” stated Dr Mark Mintun, Group Vice President, Neuroscience Research & Development, Eli Lilly and Company. “Participants continued to show meaningful outcomes, reinforcing the long-term value of early intervention.”

“With over 30 Alzheimer’s drugs now in late-stage trials globally, momentum is building – and more will enter regulatory systems in the years ahead… Government must work with NICE, the NHS and industry to pilot licensed drugs, gather more data, and prepare the health system for what’s ahead,” Hilary Evans-Newton, Chief Executive at Alzheimer’s Research UK, shared following the National Institute for Health and Care Excellence (NICE)’s recommendation last month against approval of Kisunla (donanemab) and Leqembi (lecanemab) for mild cognitive impairment or mild dementia caused by Alzheimer’s.