GSK and Alector discontinued the Phase 2 PROGRESS-AD trial of nivisnebart (AL101/GSK4527226) in early Alzheimer's disease after an independent data monitoring committee determined the trial was unlikely to meet its primary endpoint of slowing disease progression15
This represents Alector's third clinical setback in under two years, following failures of latozinemab in frontotemporal dementia (October 2025) and AL002 in Alzheimer's disease (November 2024)1
The PROGRESS-AD trial involved 367 patients with early Alzheimer's randomized to receive one of two doses of nivisnebart or placebo2
Nivisnebart is an anti-sortilin 1 antibody designed to elevate progranulin levels, a protein that supports neurons and microglia in the brain2
Both failed molecules (latozinemab and nivisnebart) share the same progranulin-boosting mechanism, leading analysts to question the viability of this therapeutic approach2
GSK paid $700 million upfront to partner with Alector in 2021, securing the right to co-develop two drug candidates, both of which have now failed2
The trial discontinuation effectively ends the GSK-Alector partnership and has triggered significant staff reductions at Alector, including a 49% workforce reduction following latozinemab's failure1
Sources:
1. https://www.biospace.com/drug-development/gsk-partnered-alector-hit-with-third-neuro-failure-as-alzheimers-asset-disappoints
2. https://www.fiercebiotech.com/biotech/gsks-700m-alector-bet-blows-alzheimers-drug-flunks-phase-2
5. https://www.globenewswire.com/news-release/2026/04/29/3284236/0/en/alector-to-discontinue-phase-2-progress-ad-trial-of-nivisnebart-al101-gsk4527226-in-early-alzheimer-s-disease-following-interim-futility-analysis.html