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[00:00.04]Researchers are renewing efforts

[00:03.36]to find Alzheimer's disease treatments

[00:06.88]that remove harmful proteins from the brain.

[00:11.64]Such vaccines could possibly offer

[00:15.20]an easier and lower-cost choice

[00:18.76]for millions of people,

[00:21.28]several scientists and industry leaders say.

[00:26.52]The brain-wasting disease

[00:28.76]causes thinking and memory problems.

[00:33.12]The U.S. government website ClinicalTrials.gov

[00:37.88]shows that at least seven possible Alzheimer's vaccines

[00:42.88]are in human testing or have completed such trials.

[00:49.12]The experimental treatments

[00:51.68]are designed to use the body's natural defense system

[00:56.40]to destroy Alzheimer's-linked proteins in the brain.

[01:02.36]The proteins are beta amyloid and tau.

[01:07.16]The renewed interest in Alzheimer's vaccines

[01:10.80]follows a promising first attempt

[01:13.88]more than 20 years ago.

[01:17.56]That vaccine work halted after six percent of study volunteers

[01:23.96]developed a life-threatening brain condition

[01:27.40]called meningoencephalitis.

[01:31.76]Researchers then found a safer method

[01:35.36]using closely targeted synthetic antibodies in patients.

[01:41.64]These antibodies avoid extreme immune system reaction.

[01:47.92]Health care companies Eisai and Biogen

[01:51.84]launched a new medication called Leqembi

[01:55.64]and health care company Eli Lilly launched Donanemab.

[02:02.24]American government drug experts

[02:05.08]are reviewing the treatments.

[02:08.44]The reported success of the drugs

[02:10.96]has strengthened the theories that amyloid

[02:14.36]removal is critical to fighting Alzheimer's.

[02:19.00]Scientists believe they now understand

[02:22.24]what went wrong with the first vaccine.

[02:26.32]They are testing shots they hope will cause an immune reaction

[02:31.12]without causing too much inflammation.

[02:35.36]Dr. Reisa Sperling is an Alzheimer's researcher

[02:39.52]at Mass General Brigham in Boston.

[02:44.44]She said she believes vaccines

[02:47.04]will play an important part

[02:49.68]as researchers look to prevent Alzheimer's.

[02:54.56]She said, "I'm very keen

[02:57.08]that that's where we need to go."

[03:00.56]Sperling is leading a trial

[03:02.80]in people with Alzheimer's proteins in their brains

[03:06.56]but showing no signs of related problems.

[03:11.52]She is considering vaccines for her next study

[03:15.04]in people who have Alzheimer's proteins in their blood,

[03:19.64]but not enough to show on imaging of the brain.

[03:24.56]Alzheimer's vaccines are still in the early stages

[03:29.12]and will require large,

[03:31.36]years-long trials to show they work.

[03:35.44]But a vaccine given two or four times a year

[03:39.44]could offer a lower-cost solution than Leqembi.

[03:45.56]Leqembi is given twice a month.

[03:48.68]That could expand available treatment

[03:52.20]among the estimated 39 million people

[03:56.00]around the world with Alzheimer's.

[04:00.00]Dr. Walter Koroshetz is director of the part of

[04:04.48]U.S. National Institutes of Health

[04:07.32]that deals with disorders involving the brain.

[04:11.72]He said of the vaccines,

[04:13.92]"They could be worldwide, and not that expensive."

[04:18.64]I'm Gregory Stachel.

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Words in This Story

synthetic – adj. made by combining different substances: not natural

antibodies – n. a substance produced by the body to fight disease

immune system – n. the system that protects your body from diseases and infections

inflammation – n. a condition in which a part of your body becomes red, swollen, and painful

keen – adj. very excited about and interested in something

trial – n. a test of the quality, value, or usefulness of something