A Phase 2 clinical trial has found that a carefully formulated oral combination of THC and CBD reduced agitation in nearly nine out of ten people with advanced Alzheimer’s or other dementias. The LiBBY study, presented at the Alzheimer’s Association International Conference in London, enrolled 120 participants in hospice or eligible for hospice care across ten US medical centres. After twelve weeks, 87.2 per cent of those receiving the cannabinoid treatment showed overall improvement, compared with 23.6 per cent on placebo, and agitation scores dropped by 8.23 points more than the control group. Researchers at the University of South Carolina and Georgetown University described the results as a level of response not previously seen in dementia agitation trials, though they cautioned that the investigational medicine differs markedly from unregulated commercial cannabis products and the data have not yet been peer-reviewed.

A separate study presented at the same conference offered early evidence for a different approach: lowering production of the tau protein rather than clearing existing tangles. Biogen’s diranersen, an antisense oligonucleotide injected into the spinal fluid every six months, was tested in roughly 400 people with mild cognitive impairment or mild Alzheimer’s. The trial missed its primary goal of showing a dose-response relationship, but the lowest dose produced a 26 per cent reduction in cognitive decline on one measure—comparable to the effect of approved anti-amyloid drugs. The Massachusetts-based company is planning a larger confirmatory study, while independent researchers in Boston and Phoenix urged caution, noting the counterintuitive dose finding and the need for replication.

These pharmacological advances arrive against a backdrop of growing evidence that diet, exercise and early-life education powerfully shape cognitive trajectories. A two-year structured programme across 11 Latin American countries, combining supervised physical activity, personalised brain-healthy nutrition and cognitive training, improved memory and executive function in over 1,000 at-risk adults aged 60 to 77. Separately, the World Health Organization’s Southeast Asia office has flagged that only 3.3 per cent of Indonesians over five meet the recommended five daily servings of fruit and vegetables, linking ultra-processed food consumption to rising non-communicable disease. Neurologists in Buenos Aires and nutrition scientists in Boston alike stress that no single food or supplement is a panacea; rather, consistent habits—from consuming leafy greens and fatty fish to maintaining social ties and a sense of purpose—build resilience over decades.

The immediate next step for both drug candidates is larger, longer trials to confirm efficacy and safety. Biogen intends to advance diranersen into Phase 3, while the LiBBY investigators emphasise that their formulation requires rigorous manufacturing and medical supervision, not over-the-counter substitution. Regulatory review and peer-reviewed publication will be the milestones to watch, alongside ongoing policy efforts in Southeast Asia to introduce front-of-pack labelling and fiscal measures that steer diets away from ultra-processed products and toward whole foods.