New and emerging treatments for Alzheimer's disease

Alzheimer's disease and other dementias represent a significant and increasing clinical challenge. Dementia is also associated with a substantial economic cost and burden to health service provision. Existing treatments slow the progression of symptoms of the disease, but their efficacy does not extend to all patients and is not sustained beyond an average of 6 months. It is, therefore, critical to address the current lack of effective treatments to target the underlying pathology and disease process in Alzheimer's disease.

This review aims to highlight the main areas of new therapeutic development and discuss some of the main therapies currently being evaluated in clinical trials. Despite a number of promising rationales for therapeutic treatments in Alzheimer's disease, very few of these avenues have been developed beyond preclinical studies. The predominant focus of the current article is on treatments currently in Phase II and Phase III clinical trials, but some other promising areas of development are also discussed. There are currently only three therapeutics being investigated in Phase III clinical trials. This emphasizes the substantial caution and underinvestment in treatment development in this area.

There is a distinct lack of novel approaches in the pipeline, and whether there is a new disease-modifying therapy for Alzheimer's disease in the next 5 years almost entirely depends on the success of currently ongoing immunotherapy studies. Importantly, there is potential benefit in exploring existing licensed treatments alongside novel drug development to increase the focus on novel targets within this time frame.