Anti-Tau Agent Warrants Phase 3 Study in AD

While the effects of anti-amyloid agents in Alzheimer's disease (AD) have been less than overwhelming (see here and here, for example), a phase 2 study presented at the recent International Conference on Alzheimer's Disease suggests that going after tangle-related tau protein may be more fruitful.

A formulation of methylene blue—yeah, the Wright's stain agent—produced a significant 5.5-point difference (vs placebo) on the ADAS-cog at 24 weeks in patients with moderate AD. The proprietary drug, trade name "rember" (ugh), was assessed in an initial double-blind, randomized, placebo-controlled, dose-ranging study in mild-to-moderate AD (N = 321), followed by a blinded, extension phase. Pooled data after 19 months revealed a significant 6.8-point difference on the ADAS-cog in patients with either mild or moderate AD. Statistically significant cognitive changes at both time points were observed with the dosage of 60 mg tid, versus initial placebo treatment.

Rember was evidently well tolerated in the phase 2 trial, except for a high incidence of diarrhea, which may depend on the drug's intestinal absorption. Reports indicate that the efficacy and tolerability of a 100-mg dose may have been compromised because of formulation problems.

Rember is an investigational agent of TauRx Therapeutics and inhibits in-vitro tau aggregation, the foundation of AD's neurofibrillary tangles. The clinical study was headed and presented by Claude M. Wischik, MBChB, of the University of Aberdeen, who also happens to be founder and executive chairman of TauRx.

A large phase 3 trial of rember in AD is planned but awaits FDA approval.

Primary sources: Medpage Today; AP via Yahoo.