Japanese drugmaker Eisai and US-based Biogen have been working together on advancing research in the space of Alzheimer’s for nearly a decade. Finally, the FDA, granted the fruits of that labor, Leqembi, its blessing for intravenous use. This marks the first approved treatment that can slow the progression of Alzheimer’s.

Leqembi received a preliminary approval in January that allowed it to be used in a limited capacity. That approval was conditioned on the two drug makers conducting a confirmatory study to verify the drug's clinical benefit.

Though Leqembi slows Alzihmer’s progression, it is not a cure. Instead, it addresses the underlying biology that spurs Alzheimer's advancement. The drug works by reducing amyloid plaques, or "misfolded" proteins that form in the brain of a person with Alzheimer's.

Leqembi isn’t the only drug targeting beta-amyloid plaque buildup to treat Alzheimer's. Aduhelm received approval under the accelerated pathway in 2021, but it’s still not fully FDA-approved. But what sets Leqembi apart from its predecessor is that the drug demonstrated actual clinical benefit in addition to simply reducing the buildup of the AD-inducing proteins.

Besides needing a medical prescription, taking the drug will require professional administration in a hospital or infusion center every two weeks. The company, though it may not be its sole responsibility, recognizes its need to boost accessibility. In a public statement, Christopher Viehbacher, the CEO of Biogen, said the company’s main focus now is to work with Eisai to make Leqembi “accessible to eligible patients as soon as possible.”

The drug’s hefty price tag of $26,500 will unfortunately make it inaccessible to most. Current rules mean that it’s unlikely to be covered by Medicare. According to the Alzheimer's Association, those on Medicaid only should be able to get coverage of the FDA-approved drug in most cases. But, even if Medicaid does cover it, patients would be responsible for a 20 percent copay – or about $5,300. Experts predict the total cost of Leqembi treatment can run upward of $90,000 a year, if you take infusions and laboratory tests into account.

An expensive treatment program is something to consider for the one in nine Americans who are over the age of 65 that have Alzheimer’s dementia. That number is expected to grow as the nation’s aging population continues to grow. The number of Americans 65 and older is projected to climb from 58 million in 2021 to 88 million by 2050. This has led to an increased focus on treatments and diagnostics for Alzheimer’s, like blood tests that can detect the disease.

When doctors need to confirm an Alzheimer's diagnosis, they often turn to a combination of brain imaging and cell analysis. Both have their downsides. The latter involves a lumbar puncture, an invasive and painful procedure that’s more commonly known as a spinal tap. A doctor will insert a needle into the lower back to extract a sample of the patient’s cerebrospinal fluid. A lab technician then tests the sample for signs of progressive nerve cell loss and excessive amyloid and tau protein accumulation. MRI scans are less invasive but they’re often expensive and accessibility is an issue; not every community has access to the technology.

The next best tool for diagnosing Alzheimer’s disease is a blood test. While some can detect abnormal tau protein counts, they’re less effective at spotting the telltale signs of neurodegeneration. But that could soon change. This week, in the journal Brain, a multinational team made up of researchers from Sweden, Italy, the UK and US detailed a new antibody-based blood test they recently developed. The new test can detect brain-derived tau proteins, which are specific to Alzheimer’s disease. Following a study of 600 patients, the team found their test could reliably distinguish the illness from other neurodegenerative diseases.

Dr. Thomas Karikari, a professor of psychiatry at the University of Pittsburgh and one of the co-authors of the study, told The Guardian he hopes the breakthrough could help other researchers design better clinical trials for Alzheimer’s treatments. “A blood test is cheaper, safer and easier to administer, and it can improve clinical confidence in diagnosing Alzheimer’s and selecting participants for clinical trial and disease monitoring,” he said. There’s more work to be done before the test makes its way to your local hospital. To start, the team needs to validate that it works for a wide variety of patients, including those who come from different ethnic backgrounds.

A study by MIT scientists on a group of epilepsy patients discovered that a specific group of neurons in their brains respond only to singing — and not to instrumental music or any other type of sound. The findings of the study were published today in the science journal Current Biology. Scientists are still working to nail down the implications of the study for epilepsy patients, some of whom rely on music as a form of therapy to reduce seizures.

“The work provides evidence for relatively fine-grained segregation of function within the auditory cortex, in a way that aligns with an intuitive distinction within music,” says Sam Norman-Haignere, the lead author of the study and assistant professor of neuroscience at the University of Rochester Medical Center.

Given how small and specific the study's sample size is (fifteen people), there's not much we can conclude from this single study alone. But it will likely advance further studies on the link between neuroscience, epilepsy and music in the future.

The study’s participants were a group of fifteen epilepsy patients, all whom consented to have electrodes implanted in their skull. They were then asked to listen to hundreds of different sounds, both natural and synthesized. Scientists, assisted by fMRI, or functional magnetic resonance imaging, observed how neurons in the auditory cortex of participants reacted to each sound.

Back in 2015, the same researchers used fMRI imaging to identify what they believe are a group of neurons that respond only to music. 

The neurons only elicited mild reactions when hearing the sound of human voices, but fired up at the sound of instrumental or vocal music. In the new study, the researchers found that there was a special subset of neurons right next to the original group that specifically lights up when the brain hears human singing.

"There's one population of neurons that responds to singing, and then very nearby is another population of neurons that responds broadly to lots of music. At the scale of fMRI, they're so close that you can't disentangle them, but with intracranial recordings, we get additional resolution, and that's what we believe allowed us to pick them apart," says Norman-Haignere.

The research could also advance our understanding of the link between music and epilepsy. While certain kinds of music can reduce the number of seizures that epilepsy patients suffer from, some rare cases of epilepsy can also be provoked by music. One recent study published in Scientific Reports last year found that listening to 30 seconds of Mozart’s “Sonata for Two Pianos in D Major” helped drive down the neuron activity that causes seizures in epilepsy patients.