Japan’s Ministry of Health, Labour and Welfare has approved Eli Lilly and Co.’s Kisunla (donanemab) for adults with early symptomatic Alzheimer’s disease (AD). This includes individuals with mild cognitive impairment (MCI) and those in the mild dementia stage of AD, all with confirmed amyloid pathology. This marks the second major market where Kisunla has been cleared for use, following its approval in the United States.
The approval comes at a critical time for Japan, where the number of dementia patients is projected to surpass 5 million by 2030. Alzheimer’s disease is the leading cause of dementia, accounting for over 67% of cases.
Kisunla’s mechanism of action focuses on targeting amyloid plaques, which are protein clusters that accumulate in the brain and are thought to be linked to the cognitive decline associated with Alzheimer’s disease. The drug works by helping the body remove these excessive amyloid plaques, thus slowing the progression of the disease.
This approval is based on the positive results from the TRAILBLAZER-ALZ 2 Phase 3 clinical study. The study demonstrated that individuals in the earlier stages of the disease who received Kisunla showed a significant 35% slowing of decline compared to those who received a placebo, as measured by the integrated Alzheimer’s Disease Rating Scale (iADRS). This scale assesses memory, thinking, and daily functioning.
The study also found that, overall, the response to treatment was statistically significant using the iADRS, with a 22% improvement in the Kisunla group compared to placebo. Participants in the Kisunla group had a 39% lower risk of progressing to the next clinical stage of the disease compared to those on placebo.
Beyond slowing cognitive decline, Kisunla also significantly reduced amyloid plaques. At six months, amyloid plaque levels were reduced by an average of 61% in the Kisunla group compared to baseline. This reduction reached 80% at 12 months and 84% at 18 months. Importantly, 66% of patients in the TRAILBLAZER-ALZ 2 study achieved plaque clearance after one year of treatment.
While Kisunla holds promise in the fight against Alzheimer’s disease, it’s important to note that it can cause amyloid-related imaging abnormalities, which is a potential side effect associated with amyloid plaque-targeting therapies.
Following this news, shares of Eli Lilly (LLY) were trading higher by 0.05% to $919.01 premarket.
The approval of Kisunla in Japan signifies a significant step forward in the battle against Alzheimer’s disease, offering hope for a future where individuals with early-stage AD have access to effective treatment options that can slow the progression of this debilitating condition.
