How Leqembi became the biggest news in Alzheimer’s disease in 40 years, and what comes next
A few months ago, Betsy Groves traveled less than a mile from her home in Cambridge, Mass. to give a talk to a bunch of scientists. The scientists, who worked for the pharmaceutical companies Biogen and Eisai, wanted to know how she lived her life, how she thought about her future, and what it was like when a doctor’s appointment in 2021 gave her the worst possible news. Groves, 73, has Alzheimer’s disease. She caught it early, through a lumbar puncture that showed evidence of amyloid, an Alzheimer’s hallmark, in her cerebrospinal fluid. As a way of dealing with her diagnosis, she joined the Alzheimer’s Association’s National Early-Stage Advisory Board, which helped her shift into seeing her diagnosis as something she could use to help others.
After her talk, Groves stayed for lunch with the scientists, who were eager to put a face to their work. Biogen and Eisai were about to release the first drug to successfully combat Alzheimer’s in 40 years of experimental disaster. Their drug, which is known by the scientific name lecanemab and the marketing name Leqembi, was granted accelerated approval by the U.S. Food and Drug Administration last Friday, Jan. 6, after a study in 1,800 people showed that it reduced cognitive decline by 27 percent over 18 months.
It is no exaggeration to say that this result is a huge deal. The field of Alzheimer’s drug development has been absolutely littered with failures. Almost everything researchers have tried has tanked in clinical trials. “Most of the things that we've done have proven not to be effective, and it's not because we haven’t been taking a ton of shots at goal,” says Anton Porsteinsson, director of the University of Rochester Alzheimer's Disease Care, Research, and Education Program, who worked on the lecanemab trial. “I think it's fair to say you don't survive in this field unless you're an eternal optimist.”
As far back as 1984, a cure looked like it was within reach: Scientists discovered that the sticky plaques that develop in the brains of those who have Alzheimer’s are made up of a protein fragment called beta-amyloid. Buildup of beta-amyloid seemed to be sufficient to disrupt communication between, and eventually kill, memory cells. If that was true, then the cure should be straightforward: Stop the buildup of beta-amyloid; stop the Alzheimer’s disease.
It wasn’t so simple. Over the next 38 years, hundreds of drugs designed either to interfere with the production of abnormal amyloid or to clear it from the brain flamed out in trials. It got so bad that neuroscience drug divisions at major pharmaceutical companies (AstraZeneca, Pfizer, Bristol-Myers, GSK, Amgen) closed one by one, leaving the field to smaller, scrappier companies, like Cambridge-based Biogen and Tokyo-based Eisai. Some scientists began to dismiss the amyloid hypothesis altogether: If this protein fragment was so important to the disease, why didn’t ridding the brain of it do anything for patients? There was another abnormal protein that showed up in the brains of Alzheimer’s patients, called tau. Some researchers defected to the tau camp, or came to believe the proteins caused damage in combination.
The situation came to a head in 2021, when the FDA granted provisional approval to a drug called aducanumab, marketed as Aduhelm, against the advice of its own advisory council. The approval was based on proof that Aduhelm reduced beta-amyloid in the brain, even though one research trial showed it had no effect on people’s symptoms or daily life. Aduhelm could also cause serious side effects, like brain swelling and amyloid related imaging abnormalities (known as ARIA, these are basically micro-bleeds that appear on MRI scans). Without a clear benefit to memory loss that would make these risks worth it, Medicare refused to pay for Aduhelm among the general population. Two congressional committees launched an investigation into the drug’s approval, citing corporate greed, lapses in protocol, and an unjustifiably high price. (Aduhelm was also produced by the pharmaceutical company Biogen.)
To be clear, Leqembi is not the cure Alzheimer’s researchers hope for. While the drug is the first to show clear signs of a clinical benefit, the scientific establishment is split on how much of a difference Leqembi will make in the real world.
So far, Leqembi is like Aduhelm in that it has been given accelerated approval only for its ability to remove amyloid from the brain. Both are monoclonal antibodies that direct the immune system to attack and clear dysfunctional beta-amyloid. The difference is that, while that’s all Aduhelm was ever shown to do, Leqembi’s makers have already asked the FDA to give it full approval – a decision that would increase the likelihood that Medicare will cover it – based on data that show it also improves Alzheimer’s sufferer’s lives. Leqembi targets a different type of amyloid, a soluble version called “protofibrils,” and that appears to change the effect. “It can give individuals and their families three, six months longer to be participating in daily life and living independently,” says Claire Sexton, PhD, senior director of scientific programs & outreach for the Alzheimer's Association. “These types of changes matter for individuals and for their families.”
To be clear, Leqembi is not the cure Alzheimer’s researchers hope for. It does not halt or reverse the disease, and people do not get better. While the drug is the first to show clear signs of a clinical benefit, the scientific establishment is split on how much of a difference Leqembi will make in the real world. It has “a rather small effect,” wrote NIH Alzheimer’s researcher Madhav Thambisetty, MD, PhD, in an email to Leaps.org. “It is unclear how meaningful this difference will be to patients, and it is unlikely that this level of difference will be obvious to a patient (or their caregivers).” Another issue is cost: Leqembi will become available to patients later this month, but Eisai is setting the price at $26,500 per year, meaning that very few patients will be able to afford it unless Medicare chooses to reimburse them for it.
The same side effects that plagued Aduhelm are common in Leqembi treatment as well. In many patients, amyloid doesn’t just accumulate around neurons, it also forms deposits in the walls of blood vessels. Blood vessels that are shot through with amyloid are more brittle. If you infuse a drug that targets amyloid, brittle blood vessels in the brain can develop leakage that results in swelling or bleeds. Most of these come with no symptoms, and are only seen during testing, which is why they are called “imaging abnormalities.” But in situations where patients have multiple diseases or are prescribed incompatible drugs, they can be serious enough to cause death. The three deaths reported from Leqembi treatment (so far) are enough to make Thambisetty wonder “how well the drug may be tolerated in real world clinical practice where patients are likely to be sicker and have multiple other medical conditions in contrast to carefully selected patients in clinical trials.”
Porsteinsson believes that earlier detection of Alzheimer’s disease will be the next great advance in treatment, a more important step forward than Leqembi’s approval.
Still, there are reasons to be excited. A successful Alzheimer’s drug can pave the way for combination studies, in which patients try a known effective drug alongside newer, more experimental ones; or preventative studies, which take place years before symptoms occur. It also represents enormous strides in researchers’ understanding of the disease. For example, drug dosages have increased massively—in some cases quadrupling—from the early days of Alzheimer’s research. And patient selection for studies has changed drastically as well. Doctors now know that you’ve got to catch the disease early, through PET-scans or CSF tests for amyloid, if you want any chance of changing its course.
Porsteinsson believes that earlier detection of Alzheimer’s disease will be the next great advance in treatment, a more important step forward than Leqembi’s approval. His lab already uses blood tests for different types of amyloid, for different types of tau, and for measures of neuroinflammation, neural damage, and synaptic health, but commercially available versions from companies like C2N, Quest, and Fuji Rebio are likely to hit the market in the next couple of years. “[They are] going to transform the diagnosis of Alzheimer's disease,” Porsteinsson says. “If someone is experiencing memory problems, their physicians will be able to order a blood test that will tell us if this is the result of changes in your brain due to Alzheimer's disease. It will ultimately make it much easier to identify people at a very early stage of the disease, where they are most likely to benefit from treatment.”
Learn more about new blood tests to detect Alzheimer's
Early detection can help patients for more philosophical reasons as well. Betsy Groves credits finding her Alzheimer’s early with giving her the space to understand and process the changes that were happening to her before they got so bad that she couldn’t. She has been able to update her legal documents and, through her role on the Advisory Group, help the Alzheimer’s Association with developing its programs and support services for people in the early stages of the disease. She still drives, and because she and her husband love to travel, they are hoping to get out of grey, rainy Cambridge and off to Texas or Arizona this spring.
Because her Alzheimer’s disease involves amyloid deposits (a “substantial portion” do not, says Claire Sexton, which is an additional complication for research), and has not yet reached an advanced stage, Groves may be a good candidate to try Leqembi. She says she’d welcome the opportunity to take it. If she can get access, Groves hopes the drug will give her more days to be fully functioning with her husband, daughters, and three grandchildren. Mostly, she avoids thinking about what the latter stages of Alzheimer’s might be like, but she knows the time will come when it will be her reality. “So whatever lecanemab can do to extend my more productive ways of engaging with relationships in the world,” she says. “I'll take that in a minute.”
When Erika Schreder’s 14-year-old daughter, who is Black, had her curly hair braided at a Seattle-area salon two or three times recently, the hairdresser applied a styling gel to seal the tresses in place.
Schreder and her daughter had been trying to avoid harmful chemicals, so they were shocked to later learn that this particular gel had the highest level of formaldehyde of any product tested by the Washington State Departments of Ecology and Health. In January 2023, the agencies released a report that uncovered high levels of formaldehyde in certain hair products, creams and lotions marketed to or used by people of color. When Schreder saw the report, she mentioned it to her daughter, who told her the name of the gel smoothed on her hair.
“It was really upsetting,” said Schreder, science director at Toxic-Free Future, a Seattle-based nonprofit environmental health research and advocacy organization. “Learning that this product used on my daughter’s hair contained cancer-causing formaldehyde made me even more committed to advocating for our state to ban toxic ingredients in cosmetics and personal care products.”
In 2013, Toxic-Free Future launched Mind the Store to challenge the nation’s largest retailers in adopting comprehensive policies that eliminate toxic chemicals in their personal care products and packaging, and develop safer alternatives.
Now, more efforts are underway to expose and mitigate the harm in cosmetics, hair care and other products that children apply on their faces, heads, nails and other body parts. Advocates hope to raise awareness among parents while prompting manufacturers and salon professionals to adopt safer alternatives.
A recent study by researchers at Columbia University Mailman School of Public Health and Earthjustice, a San Francisco-based nonprofit public interest environmental law organization, revealed that most children in the United States use makeup and body products that may contain carcinogens and other toxic chemicals. In January, the results were published in the International Journal of Environmental Research and Public Health. Based on more than 200 surveys, 70 percent of parents in the study reported that their children 12 or younger have used makeup and body products marketed to youth — for instance, glitter, face paint and lip gloss.
Childhood exposure to harmful makeup and body product ingredients can also be considered an environmental justice issue, as communities of color may be more likely to use these products.
“We are concerned about exposure to chemicals that may be found in cosmetics and body products, including those that are marketed toward children,” said the study’s senior author, Julie Herbstman, a professor and director of the Columbia Center for Children's Environmental Health. The goal of the survey was to try to understand how much kids are using cosmetic and body products and when, how and why they are using them.
“There is widespread use of children’s cosmetic and body products, and kids are using them principally to play,” Herbstman said. “That’s really quite different than how adults use cosmetic and body products.” Even with products that are specifically designed for children, “there’s no regulation that ensures that these products are safe for kids.” Also, she said, some children are using adult products — and they may do so in inadvisable ways, such as ingesting lipstick or applying it to other areas of the face.
Earlier research demonstrated that beauty and personal care products manufactured for children and adults frequently contain toxic chemicals, such as lead, asbestos, PFAS, phthalates and formaldehyde. Heavy metals and other toxic chemicals in children’s makeup and body products are particularly harmful to infants and youth, who are growing rapidly and whose bodies are less efficient at metabolizing these chemicals. Whether these chemicals are added intentionally or are present as contaminants, they have been associated with cancer, neurodevelopmental harm, and other serious and irreversible health effects, the Columbia University and Earthjustice researchers noted.
“Even when concentrations of individual chemicals are low in products, the potential for interactive effects from multiple toxicants is important to take into consideration,” the authors wrote in the journal article. “Allergic reactions, such as contact dermatitis, are some of the most frequently cited negative health outcomes associated with the use of cosmetics.”
Children’s small body side, rapid growth rate and immature immune systems are biologically more prone to the effects of toxicants than adults.
Adobe Stock
In addition to children’s rapid growth rate, the study also reported that their small body size, developing tissues and organs, and immature immune systems are biologically more prone to the effects of toxicants than adults. Meanwhile, the study noted, “childhood exposure to harmful makeup and body product ingredients can also be considered an environmental justice issue, as communities of color may be more likely to use these products.”
Although adults are the typical users of cosmetics, similar items are heavily marketed to youth with attention-grabbing features such as bright colors, animals and cartoon characters, according to the study. Beyond conventional makeup such as eyeshadow and lipstick, children may apply face paint, body glitter, nail polish, hair gel and fragrances. They also may frequent social media platforms on which these products are increasingly being promoted.
Products for both children and adults are currently regulated by the U.S. Food and Drug Administration under the Federal Food, Drug, and Cosmetic Act of 1938. Also, the Fair Packaging and Labeling Act of 1967 directs the Federal Trade Commission and the FDA “to issue regulations requiring that all ‘consumer commodities’ be labeled to disclose net contents, identity of commodity, and name and place of business of the product's manufacturer, packer, or distributor.” As the Columbia University and Earthjustice authors pointed out, though, “current safety regulations have been widely criticized as inadequate.”
The Personal Care Products Council in Washington, D.C., “fundamentally disagrees with the premise that companies put toxic chemicals in products produced for children,” industry spokeswoman Lisa Powers said in an email. Founded in 1894, the national trade association represents 600 member companies that manufacture, distribute and supply most personal care products marketed in the United States.
No category of consumer products is subject to less government oversight than cosmetics and other personal care products. -- Environmental Working Group.
“Science and safety are the cornerstones of our industry,” Powers stated. For more than a decade, she wrote, “the [Council] and our member companies worked diligently with a bipartisan group of congressional leaders and a diverse group of stakeholders to enhance the effectiveness of the FDA regulatory authority and to provide the safety reassurances that consumers expect and deserve.”
Powers added that the “industry employs and consults thousands of scientific and medical experts” who study the impacts of cosmetics and personal care products and the ingredients used in them. The Council also maintains a comprehensive database where consumers can look up science and safety information on the thousands of ingredients in sunscreens, toothpaste, shampoo, moisturizer, makeup, fragrances and other products.
However, the Environmental Working Group, which empowers consumers with breakthrough research to make informed choices about healthy living, believes the regulations are still not robust enough. “No category of consumer products is subject to less government oversight than cosmetics and other personal care products,” states the organization’s website. “Although many of the chemicals and contaminants in cosmetics and personal care products likely pose little risk, exposure to some has been linked to serious health problems, including cancer.”
The group, which operates the Skin Deep Database noted that “since 2009, 595 cosmetics manufacturers have reported using 88 chemicals, in more than 73,000 products, that have been linked to cancer, birth defects or reproductive harm.”
But change, for both adults and kids, is on the horizon. The Modernization of Cosmetics Regulation Act of 2022 significantly expanded the FDA’s authority to regulate cosmetics. In May 2023, Washington state adopted a law regulating cosmetics and personal care products. The Toxic-Free Cosmetics Act (HB 1047) bans chemicals in beauty and personal care products, such as PFAS, lead, mercury, phthalates and formaldehyde-releasing agents. These bans take effect in 2025, except for formaldehyde releasers, which have a phased-in approach starting in 2026.
Industry and advocates view this as a positive development. Powers, the spokesperson, praised “the long-awaited” Modernization Cosmetics Regulation Act of 2022, which she said, “advances product safety and innovation.” Jen Lee, chief impact officer at Beautycoutner, a company that sells personal care products, also welcomes the change. “We were proud to support the Washington Toxic-Free Cosmetics Act (HB 1047) by mobilizing our community of Brand Advocates who reside in Washington State,” Lee said. “Together, they made their voices heard by sending over 1,000 emails to their state legislators urging them to support and pass the bill.”
Laurie Valeriano, executive director of Toxic-Free Future, praised the upcoming Washington state law as “a huge win for public health and the environment that will have impacts that ripple across the nation.” She added that “companies won’t make special products for Washington state.” Instead, “they will reformulate and make products safer for everyone” — adults and children.
You shouldn’t have to be a toxicologist to shop for shampoo. -- Washington State Rep. Sharlett Mena
The new legislation will require Washington state agencies to assess the hazards of chemicals used in products that can impact vulnerable populations, while providing support for small businesses and independent cosmetologists to transition to safer products.
The Toxic-Free Future team lauds the Cosmetics Act, signed in May 2023.
Courtesy Toxic-Free Future
“When we go to a store, we assume the products on the shelf are safe, but this isn’t always true,” said Washington State Rep. Sharlett Mena, a Democrat serving in the 29th Legislative District (Tacoma), who sponsored the law. “I introduced this bill (HB 1047) because currently, the burden is on the consumer to navigate labels and find safe alternatives. You shouldn’t have to be a toxicologist to shop for shampoo.”
The new law aims to protect people of all ages, but especially youth. “Children are more susceptible to the impacts of toxic chemicals because their bodies are still developing,” Mena said. “Lead, for example, is significantly more hazardous to children than adults. Also, since children, unlike adults, tend to put things in their mouths all the time, they are more exposed to harmful chemicals in personal care and other products.”
Cosmetologists and hair professionals are taking notice. “Safety should be the practitioner’s number one concern” in using products on small children, said Anwar Saleem, a hair stylist, instructor and former salon owner in Washington, D.C., who is chairman of the D.C. Board of Barbering and Cosmetology and president of the National Interstate Council of State Boards of Cosmetology. “There are so many products on the market that it can be confusing.”
Hair products designed and labeled for children's use often have milder formulations, but “every child is unique, and what works for one may not work for another,” Saleem said. He recommends doing a patch test, in which the stylist or cosmetologist dabs the product on a small, inconspicuous area of the scalp or skin and waits anywhere from an hour to a day to check for irritation before continuing to serve the client. “Performing a patch test, observing children's reactions to a product and adequately adjusting are essential.”
Saleem seeks products that are free from harsh chemicals such as sulfates, phthalates and parabens, noting that these ingredients can be irritating and drying to the hair and scalp. If a child has sensitive skin or allergies, Saleem opts for hypoallergenic products.
We also need to ensure that less toxic alternatives are available and accessible to all consumers. It’s often under-resourced, low-income populations who suffer the burden of environmental exposures and do not have access or cannot afford these safer alternatives. -- Lesliam Quirós-Alcalá.
Lesliam Quirós-Alcalá, an assistant professor in the department of environmental health and engineering at the Johns Hopkins Bloomberg School of Public Health, said current regulatory loopholes on product labeling still allow manufacturers to advertise their cosmetics and personal care products as “gentle” and “natural.” However, she said, those terms may be misleading as they don’t necessarily mean the contents are less toxic or harmful to consumers.
“We also need to ensure that less toxic alternatives are available and accessible to all consumers,” Quirós-Alcalá said, “as often alternatives considered to be less toxic come with a hefty price tag.” As a result, “it’s often under-resourced, low-income populations who suffer the burden of environmental exposures and do not have access or cannot afford these safer alternatives.”
To advocate for safer alternatives, Quirós-Alcalá suggests that parents turn to consumer groups involved in publicizing the harms of personal care products. The Campaign for Safe Cosmetics is a program of Breast Cancer Prevention Partners, a national science-based advocacy organization aiming to prevent the disease by eliminating related environmental exposures. Other resources that inform users about unsafe ingredients include the mobile apps Clearya and Think Dirty.
“Children are not little adults, so it’s important to increase parent and consumer awareness to minimize their exposures to toxic chemicals in everyday products,” Quirós-Alcalá said. “Becoming smarter, more knowledgeable consumers is the first step to protecting your family from potentially harmful and toxic ingredients in consumer products.”
A startup aims to make medicines in space
Story by Big Think
On June 12, a SpaceX Falcon 9 rocket deployed 72 small satellites for customers — including the world’s first space factory.
The challenge: In 2019, pharma giant Merck revealed that an experiment on the International Space Station had shown how to make its blockbuster cancer drug Keytruda more stable. That meant it could now be administered via a shot rather than through an IV infusion.
The key to the discovery was the fact that particles behave differently when freed from the force of gravity — seeing how its drug crystalized in microgravity helped Merck figure out how to tweak its manufacturing process on Earth to produce the more stable version.
Microgravity research could potentially lead to many more discoveries like this one, or even the development of brand-new drugs, but ISS astronauts only have so much time for commercial experiments.
“There are many high-performance products that are only possible to make in zero-gravity, which is a manufacturing capability that cannot be replicated in any factory on Earth.”-- Will Bruey.
The only options for accessing microgravity (or free fall) outside of orbit, meanwhile, are parabolic airplane flights and drop towers, and those are only useful for experiments that require less than a minute in microgravity — Merck’s ISS experiment took 18 days.
The idea: In 2021, California startup Varda Space Industries announced its intention to build the world’s first space factory, to manufacture not only pharmaceuticals but other products that could benefit from being made in microgravity, such as semiconductors and fiber optic cables.
This factory would consist of a commercial satellite platform attached to two Varda-made modules. One module would contain equipment capable of autonomously manufacturing a product. The other would be a reentry capsule to bring the finished goods back to Earth.
“There are many high-performance products that are only possible to make in zero-gravity, which is a manufacturing capability that cannot be replicated in any factory on Earth,” said CEO Will Bruey, who’d previously developed and flown spacecraft for SpaceX.
“We have a team stacked with aerospace talent in the prime of their careers, focused on getting working hardware to orbit as quickly as possible,” he continued.
“[Pharmaceuticals] are the most valuable chemicals per unit mass. And they also have a large market on Earth.” -- Will Bruey, CEO of Varda Space.
What’s new? At the time, Varda said it planned to launch its first space factory in 2023, and, in what feels like a first for a space startup, it has actually hit that ambitious launch schedule.
“We have ACQUISITION OF SIGNAL,” the startup tweeted soon after the Falcon 9 launch on June 12. “The world’s first space factory’s solar panels have found the sun and it’s beginning to de-tumble.”
During the satellite’s first week in space, Varda will focus on testing its systems to make sure everything works as hoped. The second week will be dedicated to heating and cooling the old HIV-AIDS drug ritonavir repeatedly to study how its particles crystalize in microgravity.
After about a month in space, Varda will attempt to bring its first space factory back to Earth, sending it through the atmosphere at hypersonic speeds and then using a parachute system to safely land at the Department of Defense’s Utah Test and Training Range.
Looking ahead: Ultimately, Varda’s space factories could end up serving dual purposes as manufacturing facilities and hypersonic testbeds — the Air Force has already awarded the startup a contract to use its next reentry capsule to test hardware for hypersonic missiles.
But as for manufacturing other types of goods, Varda plans to stick with drugs for now.
“[Pharmaceuticals] are the most valuable chemicals per unit mass,” Bruey told CNN. “And they also have a large market on Earth.”
“You’re not going to see Varda do anything other than pharmaceuticals for the next minimum of six, seven years,” added Delian Asparouhov, Varda’s co-founder and president.