The US Food and Drug Administration (FDA) has approved a self-injectable version of lecanemab for people with early Alzheimer's disease, marking a significant development in the treatment of the condition.

Unlike the existing intravenous formulation, which requires hour-long hospital infusions, the new treatment can be administered at home once a week in approximately 15 seconds using an auto-injector.Researchers and patient organisations believe this could reduce pressure on healthcare services and improve convenience for patients and carers.

Clinical evidence presented by the manufacturer, Eisai, suggests that patients who begin treatment early and have relatively low levels of amyloid in the brain may experience a delay in disease progression of up to 8.3 years.

Lecanemab works by targeting and helping to remove amyloid protein deposits associated with Alzheimer's disease, making it one of the first treatments aimed at modifying the underlying disease rather than simply managing symptoms.

In the UK, the intravenous version is licensed but is not currently available on the NHS after NICE concluded it was not cost-effective, largely because of the high costs associated with hospital-based infusions.

Alzheimer's Research UK and the Alzheimer's Society said the injectable formulation could improve cost-effectiveness by reducing administration costs, although they stressed that NHS diagnostic and treatment capacity would still need substantial investment before widespread use is possible.

The UK's Medicines and Healthcare products Regulatory Agency (MHRA) is expected to review the injectable version, while NICE is reconsidering evidence relating to lecanemab and is expected to publish an updated decision in the coming months.