Improving the clinical trial landscape for patients with atypical variants of Alzheimer's disease: a call to action.

Patients with atypical variants of Alzheimer's disease (AD) often present at a younger age with predominantly non-amnestic impairments and a more aggressive disease course. Historically, individuals with atypical presentations have not been included in large-scale clinical trials, which typically focus on late-onset, sporadic amnestic-predominant AD. Consequently, treatment options and research efforts specific to atypical AD remain limited. The emergence of amyloid-targeting therapies that slow disease progression underscores these challenges, as evidence supporting their efficacy in early-onset amnestic and non-amnestic AD variants is scarce. This perspective article argues that atypical AD represents an excellent disease model for clinical trials and proposes strategies to address critical gaps in clinical trial design for this population. Key considerations include optimizing participant selection approaches, establishing syndrome-specific or surrogate biological and clinical endpoints, and fostering advocacy to enhance early and accurate diagnosis, equitable representation, and outcomes for these populations.