Merck & Co. (known as MSD outside the United States and Canada) is a global pharmaceutical company with significant research programs in neurodegenerative disease therapeutics, particularly focused on tau-targeted approaches for Alzheimer's disease and progressive supranuclear palsy.
Merck has developed two notable tau-targeted therapeutic programs:
MK-2214 is an anti-tau antibody developed by Merck targeting pathological tau proteins. The compound entered Phase 1 clinical trials in healthy subjects and patients with Alzheimer's disease or mild cognitive impairment. Phase 2 data were expected by end of 2025. MK-2214 represents Merck's entry into the anti-tau immunotherapy space, competing with programs from Biogen, Eli Lilly, and other pharmaceutical companies.
MK-8719 (also known as ASN120290) is an O-GlcNAcase (OGA) inhibitor developed by Merck in collaboration with Optizyme Pharmaceuticals. OGA inhibitors work by increasing O-GlcNAcylation of tau, which may competitively inhibit phosphorylation and reduce tau aggregation. MK-8719 was evaluated in Phase 1 clinical trials for progressive supranuclear palsy. While the program completed Phase 1, further development status for PSP indications has not been clearly announced.
MK-2214 is a monoclonal antibody designed to bind to pathological tau species, facilitating their clearance through immune-mediated mechanisms. Like other anti-tau antibodies in development (gosuranemab, tilavonemab, zagotenemab), MK-2214 targets the extracellular tau species believed to be involved in prion-like propagation of tau pathology across brain regions.
The O-GlcNAcase (OGA) enzyme removes O-linked N-acetylglucosamine (O-GlcNAc) modifications from proteins, including tau. In Alzheimer's disease and tauopathies, tau is typically hypoglucosylated, making it more susceptible to abnormal phosphorylation and aggregation. By inhibiting OGA, MK-8719 increases tau O-GlcNAcylation, which may:
| Compound | Indication | Mechanism | Phase | Status |
|---|---|---|---|---|
| MK-2214 | AD/MCI | Anti-tau antibody | Phase 1 → Phase 2 | Active |
| MK-8719 | PSP | OGA inhibitor | Phase 1 | Completed |
Merck has collaborated with academic institutions and other pharmaceutical companies on neurodegenerative disease research: