The U.S. Food and Drug Administration approved a new drug Thursday to slow the advancement of Alzheimer’s disease called Leqembi.

Doctors running trials confirmed the drug slows the rate of mental decline in patients by clearing beta-amyloid plaque that collects between neurons.

Researchers said that the drug can not reverse memory loss caused by Alzheimer’s, but rather slows down the degenerative disorder from taking over so quickly. Medicare said it will cover Leqembi for patients eligible for the drug.

When will it be available? Leqembi is available by prescription now. Eisai Inc, the Japanese pharmaceutical company that created Leqembi, predicts that only 100,0000 of the more than six million Americans suffering from Alzheimer’s could be diagnosed and eligible to take the drug by 2026.

Leqembi’s prescribing information will contain a warning that potential side effects in rare cases include brain swelling and bleeding. Medicare administrator Chiquita Brooks-LaSure said Leqembi’s approval was good news but that Medicare will continue to gather data on how the drug works.

This story originally appeared in WORLD. © 2023, reprinted with permission. All rights reserved.