Dementia Across the Spectrum Webinar Series – When it is not Alzheimer's Dementia: Thinking about the overlap with Frontotemporal Lobar dementia. Lewy Body Dementia (LBD) – Unique Features and Approac

Shifting Focus to Non-Alzheimer's Dementias

Dementia with Lewy bodies (DLB) and frontotemporal lobar degeneration (FTLD), including frontotemporal dementia (FTD), account for a substantial portion of non-Alzheimer's cases. DLB ranks as the second most common degenerative dementia after Alzheimer's, affecting about 1.4 million people in the United States alone, while FTD represents the leading cause in those under 60, with incidence around 2.28 per 100,000 person-years and prevalence near 9 per 100,000—comparable to DLB.

Recent years have seen accelerated activity in these areas. For DLB, CervoMed's neflamapimod advanced to Phase 3 planning after positive Phase 2b results in 2025, showing cognitive improvements and biomarker reductions. This follows years of limited options, where treatments remain symptomatic and patients face risks from misdiagnosis, including harmful antipsychotic reactions due to neuroleptic sensitivity. Survival post-diagnosis averages just 3.5 years, half that of Alzheimer's in some comparisons.

In FTLD/FTD, particularly genetic forms like those tied to GRN or C9orf72 mutations, 2025 marked the completion of the first Phase 3 trial for latozinemab by Alector, though it failed to slow progression despite elevating progranulin levels. Other efforts, including Vesper Bio's VES001 oral treatment showing safety and protein restoration in early trials, signal progress toward prevention in at-risk carriers. Multiple gene therapies and small molecules remain in Phase 1/2 or planning stages, with biomarker development critical for earlier detection.

These dementias impose heavy real-world costs. Patients experience fluctuating cognition, hallucinations, motor symptoms, and behavioral changes that strain caregivers and healthcare resources. In Canada, overall dementia cases are projected to surpass 1 million by 2030 and reach 1.7 million by 2050, driven by aging populations, with non-Alzheimer's types contributing significantly to younger-onset burdens and misattribution risks.

Non-obvious tensions include overlaps between pathologies—Lewy body copathology in some FTLD cases—and diagnostic challenges, where LBD's prodromal phase can last up to 15 years, delaying intervention. Emerging biomarkers promise better differentiation from Alzheimer's, but large-scale validation lags, creating trade-offs between rapid trial design and evidence certainty. Stakeholder pressures mount as pharma interest grows in rarer targets, yet failed trials underscore the biological complexity beyond simple protein elevation.