New drug for schizophrenia could meet desperate need for better treatments
The field of treating schizophrenia with drugs has been stuck in a long drought but, this month, a late-stage clinical trial found a new drug called KarXT could treat a range of symptoms.
Schizophrenia is a debilitating mental health condition that affects around 24 million people worldwide. Patients experience hallucinations and delusions when they develop schizophrenia, with experts referring to these new thoughts and behaviors as positive symptoms. They also suffer from negative symptoms in which they lose important functions, suffering from dulled emotions, lack of purpose and social withdrawal.
Currently available drugs can control only a portion of these symptoms but, on August 8th, Karuna Therapeutics announced its completion of a phase 3 clinical trial that found a new drug called KarXT could treat both positive and negative symptoms of schizophrenia. It could mean substantial progress against a problem that has stymied scientists for decades.
A long-standing problem
Since the 1950s, antipsychotics have been used to treat schizophrenia. People who suffer from it are thought to have too much of a brain chemical called dopamine, and antipsychotics work by blocking dopamine receptors in the brain. They can be effective in treating positive symptoms but have little impact on the negative ones, which can be devastating for a patient’s quality of life, making it difficult to maintain employment and have successful relationships. About 30 percent of schizophrenia patients don't actually respond to antipsychotics at all. Current drugs can also have adverse side effects including elevated cholesterol, high blood pressure, diabetes and movements that patients cannot control.
The recent clinical trial heralds a new treatment approach. “We believe it marks an important advancement for patients given its new and completely different mechanism of action from current therapies,” says Andrew Miller, COO of Karuna.
Scientists have been looking to develop alternatives. However, “the field of drug treatment of schizophrenia is currently in the doldrums,” says Peter McKenna, a senior researcher at FIDMAG Research Foundation in Spain which specialises in mental health.
In the 2000s there was a major push to target a brain receptor for a chemical called glutamate. Evidence suggested that this receptor is abnormal in the brains of schizophrenia patients, but attempts to try glutamate failed in clinical trials.
After that, many pharmaceutical companies dropped out of the race for a more useful treatment. But some companies continued to search, such as Karuna Therapeutics, led by founder and Chief Operating Officer Andrew Miller and CEO Steve Paul. The recent clinical trial suggests their persistence has led to an important breakthrough with their drug, KarXT. “We believe it marks an important advancement for patients given its new and completely different mechanism of action from current therapies,” Miller says.
How it works
Neurotransmitters are chemical messengers that pass signals between neurons. To work effectively, neurotransmitters need a receptor to bind to. A neurotransmitter called acetylcholine seems to be especially important in schizophrenia. It interacts with sites called muscarinic receptors, which are involved in the network of nerves that calm your body after a stressful event. Post mortem studies in people with schizophrenia have shown that two muscarinic receptors in the brain, the M1 and M4 receptors, are activated at unusually low levels because they don’t receive enough signals from acetylcholine.
The M4 receptor appears to play a role in psychosis. The M1 receptor is also associated with psychosis but is primarily thought to be involved in cognition. KarXT, taken orally, works by activating both of these receptors to signal properly. It is this twofold action that seems to explain its effectiveness. “[The drug’s] design enables the preferential stimulation of these muscarinic receptors in the brain,” Miller says.
How it developed
It all started in the early 1990s when Paul was at pharmaceutical company Eli Lilly. He discovered that Xanomeline, the drug they were testing on Alzheimer's patients, had antipsychotic effects. It worked by stimulating M1 and M4 receptors, so he and his colleagues decided to test Xanomeline on schizophrenia patients, supported by research on the connection between muscarinic receptors and psychosis. They found that Xanomeline reduced both positive and negative symptoms.
Unfortunately, it also caused significant side effects. The problem was that stimulating the M1 and M4 receptors in the brain also stimulated muscarinic receptors in the body that led to severe vomiting, diarrhea and even the temporary loss of consciousness.
In the end, Eli Lilly discontinued the clinical trials for the drug, but Miller set up Karuna Therapeutics to develop a solution. “I was determined to find a way to harness the therapeutic benefit demonstrated in studies of Xanomeline, while eliminating side effects that limited its development,” Miller says.
He analysed over 7,000 possible ways of mixing Xanomeline with other agents before settling on KarXT. It combines Xanomeline with a drug called Trospium Chloride, which blocks muscarinic receptors in the body – taking care of the side effects such as vomiting – but leaves them unblocked in the brain. Paul was so excited by Miller’s progress that he joined Karuna after leaving Eli Lilly and founding two previous startups.
“It's a very important approach,” says Rick Adams, Future Leaders Fellow in the Institute of Cognitive Neuroscience and Centre for Medical Image Computing at University College London. “We are in desperate need of alternative drug targets and this target is one of the best. There are other alternative targets, but not many are as close to being successful as the muscarinic receptor drug.”
Clinical Trial
Following a successful phase 2 clinical trial in 2019, the most recent trial involved 126 patients who were given KarXT, and 126 who were given a placebo. Compared to the placebo, patients taking KarXT had a significant 9.6 point reduction in the positive and negative syndrome scale (PANSS), the standard for rating schizophrenic symptoms.
KarXT also led to statistically significant declines in positive and negative symptoms compared to the placebo. “The results suggest that KarXT could be a potentially game-changing option in the management of both positive and negative symptoms of schizophrenia,” Miller says.
Robert McCutcheon, a psychiatrist and neuroscientist at Oxford University, is optimistic about the side effects but highlights the need for more safety trials.
McKenna, the researcher at FIDMAG Foundation, agrees about the drug’s potential. “The new [phase 3] study is positive,” he says. “It is reassuring that one is not dealing with a drug that works in one trial and then inexplicably fails in the next one.”
Robert McCutcheon, a psychiatrist and neuroscientist at Oxford University, said the drug is an unprecedented step forward. “KarXT is one of the first drugs with a novel mechanism of action to show promise in clinical trials.”
Even though the drug blocks muscarine receptors in the body, some patients still suffered from adverse side effects like vomiting, dizziness and diarrhea. But in general, these effects were mild to moderate, especially compared to dopamine-blocking antipsychotics or Xanomeline on its own.
McCutcheon is optimistic about the side effects but highlights the need for more safety trials. “The trial results suggest that gastrointestinal side effects appear to be manageable,” he says. “We know, however, from previous antipsychotic drugs that the full picture regarding the extent of side effects can sometimes take longer to become apparent to clinicians and patients. Careful ongoing assessment during a longer period of treatment will therefore be important.”
The Future
The team is currently conducting three other trials to evaluate the efficacy and long-term safety of KarXT. Their goal is to receive FDA approval next year.
Karuna is also conducting trials to evaluate the effectiveness of KarXT in treating psychosis in patients suffering from Alzheimer’s.
The big hope is that they will soon be able to provide a radically different drug to help many patients with schizophrenia. “We are another step closer to potentially providing the first new class of medicine in more than 50 years to the millions of people worldwide living with schizophrenia,” says Miller.
23andMe Is Using Customers’ Genetic Data to Develop Drugs. Is This Brilliant or Dubious?
A woman does a DNA test with a cotton swab at home.
Leading direct-to-consumer (DTC) genetic testing companies are continuously unveiling novel ways to leverage their vast stores of genetic data.
"23andMe will tell you what diseases you have and then sell you the drugs to treat them."
As reported last week, 23andMe's latest concept is to develop and license new drugs using the data of consumers who have opted in to let their information be used for research. To date, over 10 million people have used the service and around 80 percent have opted in, making its database one of the largest in the world.
Culture researcher Dr. Julia Creet is one of the foremost experts on the DTC genetic testing industry, and in her forthcoming book, The Genealogical Sublime, she bluntly examines whether such companies' motives and interests are in sync with those of consumers.
Leapsmag caught up with Creet about the latest news and the wider industry's implications for health and privacy.
23andMe has just announced that it plans to license a newly developed anti-inflammatory drug, the first one created using its customers' genetic data, to Almirall, a pharma company in Spain. What's your take?
I think this development is the next step in the evolution of the company and its "double-sided" marketing model. In the past, as it enticed customers to give it their DNA, it sold the results and the medical information divulged by customers to other drug companies. Now it is positioning itself to reap the profits of a new model by developing treatments itself.
Given that there are many anti-inflammatory drugs on the market already, whatever Almirall produces might not have much of an impact. We might see this canny move as a "proof of concept," that 23andMe has learned how to "leverage" its genetic data without having to sell them to a third party. In a way, the privacy provisions will be much less complicated, and the company stands to attract investment as it turns itself into [a pseudo pharmaceutical company], a "pharma-psuedocal" company.
Emily Drabant Conley, the president of business development, has said that 23andMe is pursuing other drug compounds and may conduct their own clinical trials rather than licensing them out to their existing research partners. The end goal, it seems, is to make direct-to-consumer DNA testing to drug production and sales back to that same consumer base a seamless and lucrative circle. You have to admit it's a brilliant business model. 23andMe will tell you what diseases you have and then sell you the drugs to treat them.
In your new book, you describe how DTC genetic testing companies have capitalized on our innate human desire to connect with or ancestors and each other. I quote you: "This industry has taken that potent, spiritual, all-too-human need to belong... and monetized it in a particularly exploitative way." But others argue that DTC genetic testing companies are merely providing a service in exchange for fair-market compensation. So where does exploitation come into the picture?
Yes, the industry provides a fee for service, but that's only part of the story. The rest of the story reveals a pernicious industry that hides its business model behind the larger science project of health and heredity. All of the major testing companies play on the idea of "lack," that we can't know who we are unless we buy information about ourselves. When you really think about it, "Who do you think you are?" is a pernicious question that suggests that we don't or can't know who we or to whom we are related without advanced data searches and testing. This existential question used to be a philosophical question; now the answers are provided by databases that acquire more valuable information than they provide in the exchange.
"It's a brilliant business model that exploits consumer naiveté."
As you've said before, consumers are actually paying to be the product because the companies are likely to profit more from selling their genetic data. Could you elaborate?
The largest databases, AncestryDNA and 23andMe, have signed lucrative agreements with biotech companies that pay them for the de-identified data of their customers. What's so valuable is the DNA combined with the family relationships. Consumers provide the family relationships and the companies link and extrapolate the results to larger and larger family trees. Combined with the genetic markers for certain diseases, or increased susceptibility to certain diseases, these databases are very valuable for biotech research.
None of that value will ever be returned to consumers except in the form of for-profit drugs. Ancestry, in particular, has removed all information about its "research partners" from its website, making it very difficult to see how it is profiting from its third-party sales. 23andMe is more open about its "two-sided business model," but encourages consumers to donate their information to science. It's a brilliant business model that exploits consumer naiveté.
A WIRED journalist wrote that "23andMe has been sharing insights gleaned from consented customer data with GSK and at least six other pharmaceutical and biotechnology firms for the past three and a half years." Is this a consumer privacy risk?
I don't see that 23andMe did anything to which consumers didn't consent, albeit through arguably unreadable terms and conditions. The part that worries me more is the 300 phenotype data points that the company has collected on its consumers through longitudinal surveys designed, as Anne Wojcicki, CEO and Co-founder of 23andMe, put it, "to circumvent medical records and just self-report."
Everyone is focused on the DNA, but it's the combination of genetic samples, genealogical information and health records that is the most potent dataset, and 23andMe has figured out a way to extract all three from consumers.
Edible Silverware Is the Next Big Thing in Sustainable Eating
A new edible spoon is durable enough for mass market assembly and is already alleviating consumer waste.
Sure, you may bring a reusable straw when you go out to eat. But what about digesting your silverware at the restaurant? The future is already here.
Edible cutlery feels like a natural progression post-reusable straw.
Air New Zealand just added the new edible coffee cup Twiice into their in-flight service. Made from vanilla, wheat flower, sugar, egg and vanilla essence, the Twiice cups will be standard issue for the international airline.
On the ground, the new, award-winning startup IncrEDIBLESpoon has shipped more than a quarter million edible scoopers. The spoons are all-natural, vegan, and made from wheat, oat, corn, chickpea and barley.
The technological breakthrough is in creating tasty, mass-market material durable enough for delivery in an assembly line environment like airplane service, as well as stable enough to hold a hot cup of coffee or a freezing scoop of ice cream. Twiice cups can last several hours after hot coffee is added, while IncrEDIBLESpoon cutlery holds up to 45 minutes.
"We already caught the interest of a couple major ice cream chains," says Dinesh Tadepalli, co-founder of the IncrEDIBLESpoon parent company Planeteer. "If all goes well, one of them will test out our spoons at their scoop shop early this year."
Next Up
Edible cutlery feels like a natural progression post-reusable straw. And more is already on the menu.
The coffee cup company Twiice is already planning on expanding. Co-founder Jamie Cashmore says other serving items are coming later this year.
IncrEDIBLESpoon is also getting into more utensils. "We plan to mass produce the complete set by year's end: Edible straws, edible forks and edible coffee stirrers," Tadepalli says.
Most notably, Twiice's partner Air New Zealand sees the coffee cup as just a start to other sustainable solutions. The airline estimates it currently serves eight million cups of coffee annually. It's even suggesting customers bring their own reusable cup to the plane – though that isn't as ergonomic nor as attractive as eating everything you are served.
Open Questions
Making everything edible has a few challenges. First is cultural acceptance: With respect to current success, changing eating habits will require going beyond eco-focused and curious eaters.
Second, it's unclear if the short-term economics will add up in favor of airline carriers and other companies. Like alternative fuel, organizations will be more likely to adopt new science when it doesn't require a retrofitting or expensive change to their current business model – even if it does create long-term benefits.
The changes will likely be lopsided, influencing cultures at different times. Airplanes are a great start, as passengers are a captive audience interested in removing waste as soon as possible.
"Imagine eating a black pepper spoon after your soup or a chocolate spoon after your ice cream?"
We can expect edible cutlery to make an easier impact with certain cultures or foods. For instance, injera, the spongy Ethiopian bread, has served as an African plate of sorts for years. It makes sense that IncrEDIBLESpoon's four flavors, Salt, Masala, Spinach and Root, all fit in another bread-as-plate friendly culture: Indian.
Coffee and desserts sound like a good bet for now, though, especially for foodies. "People are curious to try edible spoons as they never heard or experienced them before," Tadepalli says. "Imagine eating a black pepper spoon after your soup or a chocolate spoon after your ice cream?"