Eisai on Wednesday said it showed an injectable version of the Alzheimer’s drug Leqembi promising initial results in a clinical trial, potentially paving the way for a new and more convenient option for delivering antibody therapy.
However, the injection did not cause lower rates of swelling and bleeding in the brain, which are Leqembi’s most worrisome side effects.
Leqembi, made by Eisai and its partner Biogen, is the first drug shown to slow the progression of Alzheimer’s disease in people in the early stages of the memory-robbing disease. US regulators in July approved a version of Leqembi that is given twice a month through veins, which is a method known as an intravenous infusion.
But Eisai and partner Biogen hope to win approval for a subcutaneous version of the drug, which would be an injection under the skin. This method would allow patients or caregivers to administer Leqembi at home, freeing them from the need to travel to an infusion center such as a hospital every two weeks.
Eisai and Biogen said in a statement that they plan to apply for US approval for Leqembi subcutaneous by the end of March.
Eisai presented preliminary results, from an extension to a late-stage trial that supported the approval of intravenous Leqembi, at the Clinical Trials on Alzheimer’s Disease conference in Boston. This study looked at subcutaneous doses of Leqembi and measured the drug’s safety and effects on a protein called amyloid – also known as plaque – that builds up in the brain and is associated with Alzheimer’s disease.
The study showed that a set of two injections given once a week produced similar results after six months to twice-monthly intravenous infusions in terms of safety, the drug’s concentration in the blood and its ability to clear plaque buildup in the brain. Eisai said. .
The study specifically showed that the injectable form of Leqembi removed 14% more plaque than the approved intravenous formulation. Blood concentration levels of the drug were 11% higher with subcutaneous Leqembi than the other version.
But the newer form still had side effects known as amyloid-related imaging abnormalities, or ARIA. Removal of plaques from the brain can be associated with brain swelling and bleeding – also known as ARIA-E and ARIA-H – which can be serious or even fatal in rare cases.
Nearly 17% of patients who received weekly injections had ARIA-E, compared with 13% who received the drug by intravenous infusion. And 22% of downloaders had ARIA-H, compared to 17% who received the other format.
About 6.7 million Americans age 65 and older are living with Alzheimer’s, according to the Alzheimer’s Association. This group is projected to grow to nearly 13 million by 2050.
One in three seniors dies of Alzheimer’s or another form of dementia, which kills more people than breast cancer and prostate cancer combined, the association said. Neurodegenerative disease begins with mild memory loss but eventually impairs the person’s ability to think and carry out daily activities.
There is a wealth of research on Alzheimer’s disease, but it has been notoriously difficult to treat. Many drugs designed to target the disease have failed in tests. The enormous cost and length of this research further hinder drug development. And in recent years, scientists have sparked a debate about the true cause of the disease and what the drugs should target.