Researchers advance drugs that treat pain without addiction
New therapies are using creative approaches that target the body’s sensory neurons, which send pain signals to the brain.
Opioids are one of the most common ways to treat pain. They can be effective but are also highly addictive, an issue that has fueled the ongoing opioid crisis. In 2020, an estimated 2.3 million Americans were dependent on prescription opioids.
Opioids bind to receptors at the end of nerve cells in the brain and body to prevent pain signals. In the process, they trigger endorphins, so the brain constantly craves more. There is a huge risk of addiction in patients using opioids for chronic long-term pain. Even patients using the drugs for acute short-term pain can become dependent on them.
Scientists have been looking for non-addictive drugs to target pain for over 30 years, but their attempts have been largely ineffective. “We desperately need alternatives for pain management,” says Stephen E. Nadeau, a professor of neurology at the University of Florida.
A “dimmer switch” for pain
Paul Blum is a professor of biological sciences at the University of Nebraska. He and his team at Neurocarrus have created a drug called N-001 for acute short-term pain. N-001 is made up of specially engineered bacterial proteins that target the body’s sensory neurons, which send pain signals to the brain. The proteins in N-001 turn down pain signals, but they’re too large to cross the blood-brain barrier, so they don’t trigger the release of endorphins. There is no chance of addiction.
When sensory neurons detect pain, they become overactive and send pain signals to the brain. “We wanted a way to tone down sensory neurons but not turn them off completely,” Blum reveals. The proteins in N-001 act “like a dimmer switch, and that's key because pain is sensation overstimulated.”
Blum spent six years developing the drug. He finally managed to identify two proteins that form what’s called a C2C complex that changes the structure of a subunit of axons, the parts of neurons that transmit electrical signals of pain. Changing the structure reduces pain signaling.
“It will be a long path to get to a successful clinical trial in humans," says Stephen E. Nadeau, professor of neurology at the University of Florida. "But it presents a very novel approach to pain reduction.”
Blum is currently focusing on pain after knee and ankle surgery. Typically, patients are treated with anesthetics for a short time after surgery. But anesthetics usually only last for 4 to 6 hours, and long-term use is toxic. For some, the pain subsides. Others continue to suffer after the anesthetics have worn off and start taking opioids.
N-001 numbs sensation. It lasts for up to 7 days, much longer than any anesthetic. “Our goal is to prolong the time before patients have to start opioids,” Blum says. “The hope is that they can switch from an anesthetic to our drug and thereby decrease the likelihood they're going to take the opioid in the first place.”
Their latest animal trial showed promising results. In mice, N-001 reduced pain-like behaviour by 90 percent compared to the control group. One dose became effective in two hours and lasted a week. A high dose had pain-relieving effects similar to an opioid.
Professor Stephen P. Cohen, director of pain operations at John Hopkins, believes the Neurocarrus approach has potential but highlights the need to go beyond animal testing. “While I think it's promising, it's an uphill battle,” he says. “They have shown some efficacy comparable to opioids, but animal studies don't translate well to people.”
Nadeau, the University of Florida neurologist, agrees. “It will be a long path to get to a successful clinical trial in humans. But it presents a very novel approach to pain reduction.”
Blum is now awaiting approval for phase I clinical trials for acute pain. He also hopes to start testing the drug's effect on chronic pain.
Learning from people who feel no pain
Like Blum, a pharmaceutical company called Vertex is focusing on treating acute pain after surgery. But they’re doing this in a different way, by targeting a sodium channel that plays a critical role in transmitting pain signals.
In 2004, Stephen Waxman, a neurology professor at Yale, led a search for genetic pain anomalies and found that biologically related people who felt no pain despite fractures, burns and even childbirth had mutations in the Nav1.7 sodium channel. Further studies in other families who experienced no pain showed similar mutations in the Nav1.8 sodium channel.
Scientists set out to modify these channels. Many unsuccessful efforts followed, but Vertex has now developed VX-548, a medicine to inhibit Nav1.8. Typically, sodium ions flow through sodium channels to generate rapid changes in voltage which create electrical pulses. When pain is detected, these pulses in the Nav1.8 channel transmit pain signals. VX-548 uses small molecules to inhibit the channel from opening. This blocks the flow of sodium ions and the pain signal. Because Nav1.8 operates only in peripheral nerves, located outside the brain, VX-548 can relieve pain without any risk of addiction.
"Frankly we need drugs for chronic pain more than acute pain," says Waxman.
The team just finished phase II clinical trials for patients following abdominoplasty surgery and bunionectomy surgery.
After abdominoplasty surgery, 76 patients were treated with a high dose of VX-548. Researchers then measured its effectiveness in reducing pain over 48 hours, using the SPID48 scale, in which higher scores are desirable. The score for Vertex’s drug was 110.5 compared to 72.7 in the placebo group, whereas the score for patients taking an opioid was 85.2. The study involving bunionectomy surgery showed positive results as well.
Waxman, who has been at the forefront of studies into Nav1.7 and Nav1.8, believes that Vertex's results are promising, though he highlights the need for further clinical trials.
“Blocking Nav1.8 is an attractive target,” he says. “[Vertex is] studying pain that is relatively simple and uniform, and that's key to having a drug trial that is informative. But the study needs to be replicated and frankly we need drugs for chronic pain more than acute pain. If this is borne out by additional studies, it's one important step in a journey.”
Vertex will be launching phase III trials later this year.
Finding just the right amount of Nerve Growth Factor
Whereas Neurocarrus and Vertex are targeting short-term pain, a company called Levicept is concentrating on relieving chronic osteoarthritis pain. Around 32.5 million Americans suffer from osteoarthritis. Patients commonly take NSAIDs, or non-steroidal anti-inflammatory drugs, but they cannot be taken long-term. Some take opioids but they aren't very effective.
Levicept’s drug, Levi-04, is designed to modify a signaling pathway associated with pain. Nerve Growth Factor (NGF) is a neurotrophin: it’s involved in nerve growth and function. NGF signals by attaching to receptors. In pain there are excess neurotrophins attaching to receptors and activating pain signals.
“What Levi-04 does is it returns the natural equilibrium of neurotrophins,” says Simon Westbrook, the CEO and founder of Levicept. It stabilizes excess neurotrophins so that the NGF pathway does not signal pain. Levi-04 isn't addictive since it works within joints and in nerves outside the brain.
Westbrook was initially involved in creating an anti-NGF molecule for Pfizer called Tanezumab. At first, Tanezumab seemed effective in clinical trials and other companies even started developing their own versions. However, a problem emerged. Tanezumab caused rapidly progressive osteoarthritis, or RPOA, in some patients because it completely removed NGF from the system. NGF is not just involved in pain signalling, it’s also involved in bone growth and maintenance.
Levicept has found a way to modify the NGF pathway without completely removing NGF. They have now finished a small-scale phase I trial mainly designed to test safety rather than efficacy. “We demonstrated that Levi-04 is safe and that it bound to its target, NGF,” says Westbrook. It has not caused RPOA.
Professor Philip Conaghan, director of the Leeds Institute of Rheumatic and Musculoskeletal Medicine, believes that Levi-04 has potential but urges the need for caution. “At this early stage of development, their molecule looks promising for osteoarthritis pain,” he says. “They will have to watch out for RPOA which is a potential problem.”
Westbrook starts phase II trials with 500 patients this summer to check for potential side effects and test the drug’s efficacy.
There is a real push to find an effective alternative to opioids. “We have a lot of work to do,” says Professor Waxman. “But I am confident that we will be able to develop new, much more effective pain therapies.”
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?"