Developed by Singaporean company TauRx Pharmaceutics Ltd, the scientists based in Aberdeen report that hydromethylthionine mesylate (HMTM) could be the first oral treatment for Alzheimer’s disease (AD) that targets the tau protein pathology – if it is approved by regulators.
The findings were revealed at leading international conference AD/PD 2025 in Vienna, which concluded on Saturday. At the event, TauRx Pharmaceuticals CEO and co-founder Professor Claude Wischik outlined work which compared results from HMTM’s recent Phase 3 trial with placebo data from closely matched subjects available from the Critical Path in AD (CPAD) Institute database, which contains information from nearly 10,000 patients that have taken part in 36 global trials.
Prof Wischik, who led the research, said: “The results, which were consistent across three different analyses comparing HMTM with external data, show that HMTM is effective in reducing clinical decline and brain atrophy progression over a period of at least 18 months, with potentially clinically meaningful treatment benefits lasting up to two years.
“We believe that HMTM has the potential to be a safe and accessible oral treatment option for early to mild/moderate AD which could be delivered with minimal patient and physician burden.
“Although this is not a cure, the research suggests that starting HMTM treatment early in the disease process can substantially delay progression. The combination of a strong safety profile, as evidenced from trials involving more than 3,000 patients, and oral administration leads us to believe we have a drug that people would be able to take in the same way they take other prescription medication.”
TauRx has submitted a Marketing Authorisation Application for HMTM to the UK’s Medicines and Healthcare products Regulatory Agency (MHRA), while the company is also engaged with the National Institute for Health and Care Excellence (NICE) to assess the suitability of the medicine for use on the NHS.
The comparison using the ADAS-cog13 scoring system, which measures the ability to undertake tasks such as recalling words and remembering test instructions, showed patients with early disease taking HMTM did not decline significantly from their baseline score over 18 months, in contrast to the substantial decline seen in the CPAD placebo data.
In addition, examination of the Clinical Dementia Rating (CDR) scale used to provide a global assessment of dementia severity showed similar results, with progression of brain atrophy, an objective indicator of neurodegeneration, also significantly reduced for the HMTM data.
Tau protein has been at the forefront of Prof Wischik’s work since his discovery in 1988 that the Alzheimer tangle was made up of abnormally assembled tau protein forming destructive filaments inside nerve cells in the brain.
While several other drugs have focused on amyloid protein, HMTM has a different mode of action in that it targets the abnormal assembly of tau protein. It is also the only oral tau therapeutic to have completed Phase 3 trials.
