Dementia drug hailed for slowing down Alzheimer’s by up to a THIRD may be unsafe for 9 out of 10 patients

One of the first Alzheimer’s drugs capable of slowing the disease’s progression should not be given to the majority of patients due to safety concerns, a study suggests.

Research appears to show that the drug, lecanemab, can slow the degenerative brain condition by a third. And last month, US health regulators approved the twice-monthly injection for patients with mild cognitive impairment or mild dementia – meaning the Alzheimer’s is in its earliest stages.

The NHS spending watchdog is due to begin assessing the drug for use in the UK next month, hoping that it could help the one million Alzheimer’s sufferers in the UK.

But research warns that there is no data to show the drug is safe for nine out of ten early-stage Alzheimer’s patients. This is because the drug has only been tested on patients who are otherwise healthy.

Patients hoping to participate in the lecanemab trial, carried out by Japanese drug firm Eisai, could not take part if they had conditions such as obesity, diabetes, heart problems or a history of cancer.

Despite participants having a clean bill of health, there was a high rate of side effects. Around one in ten patients who took lecanemab had life-threatening brain swelling and one in six developed brain bleeds, according to data published by Eisai. Three members of the 1,800-participant trial died as a result of side effects linked to the drug.

Researchers at the Mayo Clinic, in Minnesota, US, looked at the health records of 237 older adults who suffered with mild cognitive impairment or mild dementia and found that the 92 per cent of them had an underlying health problem which would’ve excluded them from the lecanemab trial.

Dr Maria Vassilaki, epidemiologist at the Mayo Clinic and study author, said that more research was needed to examine the safety and efficacy of lecanemab before it could be offered to ‘less healthy populations.’