Tiny, Injectable Robots Could Be the Future of Brain Treatments
In the 1966 movie "Fantastic Voyage," actress Raquel Welch and her submarine were shrunk to the size of a cell in order to eliminate a blood clot in a scientist's brain. Now, 55 years later, the scenario is becoming closer to reality.
California-based startup Bionaut Labs has developed a nanobot about the size of a grain of rice that's designed to transport medication to the exact location in the body where it's needed. If you think about it, the conventional way to deliver medicine makes little sense: A painkiller affects the entire body instead of just the arm that's hurting, and chemotherapy is flushed through all the veins instead of precisely targeting the tumor.
"Chemotherapy is delivered systemically," Bionaut-founder and CEO Michael Shpigelmacher says. "Often only a small percentage arrives at the location where it is actually needed."
But what if it was possible to send a tiny robot through the body to attack a tumor or deliver a drug at exactly the right location?
Several startups and academic institutes worldwide are working to develop such a solution but Bionaut Labs seems the furthest along in advancing its invention. "You can think of the Bionaut as a tiny screw that moves through the veins as if steered by an invisible screwdriver until it arrives at the tumor," Shpigelmacher explains. Via Zoom, he shares the screen of an X-ray machine in his Culver City lab to demonstrate how the half-transparent, yellowish device winds its way along the spine in the body. The nanobot contains a tiny but powerful magnet. The "invisible screwdriver" is an external magnetic field that rotates that magnet inside the device and gets it to move and change directions.
The current model has a diameter of less than a millimeter. Shpigelmacher's engineers could build the miniature vehicle even smaller but the current size has the advantage of being big enough to see with bare eyes. It can also deliver more medicine than a tinier version. In the Zoom demonstration, the micorobot is injected into the spine, not unlike an epidural, and pulled along the spine through an outside magnet until the Bionaut reaches the brainstem. Depending which organ it needs to reach, it could be inserted elsewhere, for instance through a catheter.
"The hope is that we can develop a vehicle to transport medication deep into the body," says Max Planck scientist Tian Qiu.
Imagine moving a screw through a steak with a magnet — that's essentially how the device works. But of course, the Bionaut is considerably different from an ordinary screw: "At the right location, we give a magnetic signal, and it unloads its medicine package," Shpigelmacher says.
To start, Bionaut Labs wants to use its device to treat Parkinson's disease and brain stem gliomas, a type of cancer that largely affects children and teenagers. About 300 to 400 young people a year are diagnosed with this type of tumor. Radiation and brain surgery risk damaging sensitive brain tissue, and chemotherapy often doesn't work. Most children with these tumors live less than 18 months. A nanobot delivering targeted chemotherapy could be a gamechanger. "These patients really don't have any other hope," Shpigelmacher says.
Of course, the main challenge of the developing such a device is guaranteeing that it's safe. Because tissue is so sensitive, any mistake could risk disastrous results. In recent years, Bionaut has tested its technology in dozens of healthy sheep and pigs with no major adverse effects. Sheep make a good stand-in for humans because their brains and spines are similar to ours.
The Bionaut device is about the size of a grain of rice.
Bionaut Labs
"As the Bionaut moves through brain tissue, it creates a transient track that heals within a few weeks," Shpigelmacher says. The company is hoping to be the first to test a nanobot in humans. In December 2022, it announced that a recent round of funding drew $43.2 million, for a total of 63.2 million, enabling more research and, if all goes smoothly, human clinical trials by early next year.
Once the technique has been perfected, further applications could include addressing other kinds of brain disorders that are considered incurable now, such as Alzheimer's or Huntington's disease. "Microrobots could serve as a bridgehead, opening the gateway to the brain and facilitating precise access of deep brain structure – either to deliver medication, take cell samples or stimulate specific brain regions," Shpigelmacher says.
Robot-assisted hybrid surgery with artificial intelligence is already used in state-of-the-art surgery centers, and many medical experts believe that nanorobotics will be the instrument of the future. In 2016, three scientists were awarded the Nobel Prize in Chemistry for their development of "the world's smallest machines," nano "elevators" and minuscule motors. Since then, the scientific experiments have progressed to the point where applicable devices are moving closer to actually being implemented.
Bionaut's technology was initially developed by a research team lead by Peer Fischer, head of the independent Micro Nano and Molecular Systems Lab at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany. Fischer is considered a pioneer in the research of nano systems, which he began at Harvard University more than a decade ago. He and his team are advising Bionaut Labs and have licensed their technology to the company.
"The hope is that we can develop a vehicle to transport medication deep into the body," says Max Planck scientist Tian Qiu, who leads the cooperation with Bionaut Labs. He agrees with Shpigelmacher that the Bionaut's size is perfect for transporting medication loads and is researching potential applications for even smaller nanorobots, especially in the eye, where the tissue is extremely sensitive. "Nanorobots can sneak through very fine tissue without causing damage."
In "Fantastic Voyage," Raquel Welch's adventures inside the body of a dissident scientist let her swim through his veins into his brain, but her shrunken miniature submarine is attacked by antibodies; she has to flee through the nerves into the scientist's eye where she escapes into freedom on a tear drop. In reality, the exit in the lab is much more mundane. The Bionaut simply leaves the body through the same port where it entered. But apart from the dramatization, the "Fantastic Voyage" was almost prophetic, or, as Shpigelmacher says, "Science fiction becomes science reality."
This article was first published by Leaps.org on April 12, 2021.
More than 20 percent of American adults suffer from chronic pain. And as many as one in four of those prescribed opioids to manage that pain go on to misuse – or abuse – them, often with devastating consequences. Patients afflicted by both chronic pain and opioid addiction are especially difficult to treat, according to Eric Garland, PhD, Director of the University of Utah’s Center on Mindfulness and Integrative Health Intervention Development, because opioid overuse increases pain sensitivity, and pain promotes relapse among those being treated for addiction.
A new study, however, shows that a mindfulness-based therapy can successfully tackle both problems at once, pointing to a tool that could potentially help in fighting the opioid crisis. “This is the first large-scale clinical trial to show that any psychological intervention can reduce opioid misuse and chronic pain for the long term,” says Garland, lead author of the study, published February 28th in JAMA Internal Medicine.
Garland’s study focused on 250 adults who had received opioid therapy for chronic pain for 90 days or longer, randomly assigning them to eight weeks of either a standard psychotherapy support group or Mindfulness-Oriented Recovery Enhancement (MORE) therapy, which combines mindfulness training, cognitive-behavioral therapy (CBT) and positive psychology. Nine months after getting these treatments in primary care settings, 45 percent of patients in the MORE group were no longer misusing opioids, compared to 24 percent of those in group therapy. In fact, about a third of the patients in the MORE group were able to cut their opioid dose in half or reduce it even further.
Patients treated with MORE also experienced more significant pain relief than those in support groups, according to Garland. Conventional approaches to treating opioid addiction include 12-step programs and medically-assisted treatment using drugs like methadone and Suboxone, sometimes coupled with support groups. But patients with Opioid Use Disorder (OUD) – the official diagnosis for opioid addiction – have high relapse rates following treatment, especially if they have chronic pain.
While medically-assisted treatments help to control drug cravings, they do nothing to control chronic pain, which is where psychological therapies like MORE come in.
“For patients suffering from moderate pain and OUD, the relapse rate is three times higher than in patients without chronic pain; for those with severe chronic pain, the relapse rate is five times higher,” says Amy Wachholtz, PhD, Director of Clinical Health Psychology and associate professor at University of Colorado in Denver. “So if we don’t treat the chronic pain along with the OUD addiction simultaneously, we are setting patients up for failure.”
Unfortunately, notes Garland, the standard of care for patients with chronic pain who are misusing their prescribed painkillers is “woefully inadequate.” Many patients don’t meet the criteria for OUD, he says, but instead fall into a gray zone somewhere between legitimate opioid use and full-blown addiction. And while medically-assisted treatments help to control drug cravings, they do nothing to control chronic pain, which is where psychological therapies like MORE come in. But behavioral therapies are often not available in primary care settings, and even when clinicians do refer patients to behavioral health providers, they often prescribe CBT. A large scale study last year showed that CBT – without the added components of mindfulness training and positive psychology – reduced pain but not opioid misuse.
Psychotherapist Eric Garland teaches mindfulness.
University of Utah
Reward Circuitry Rewired
Opioids are highly physiologically addictive. Repeated and high-dose drug use causes the brain to become hypersensitive to stress, pain, and drug-related cues, such as the sight of one’s pill bottle, says Garland, while at the same time becoming increasingly insensitive to natural pleasures. “As an individual becomes more and more dependent on the opioids just to feel okay, they feel less able to extract a healthy sense of joy, pleasure and meaning out of everyday life,” he explains. “This drives them to take higher and higher doses of the opioid to maintain a dwindling sense of well-being.”
The changes are not just psychological: Chronic opioid use actually causes changes in the brain’s reward circuitry. “You can see on brain imaging,” says Garland. “The brain’s reward circuitry becomes more responsive when a person is viewing opioid related images than when they are viewing images of smiling babies, lovers holding hands, or sunsets over the beach.” MORE, he says, teaches “savoring” – a tenet of positive psychology – as a means of restructuring the reward processes in the brain so the patient becomes sensitive to pleasure from natural, healthy rewards, decreasing cravings for drug-related rewards.
Mindfulness and Addiction
Mindfulness, a form of meditation that teaches people to observe their feelings and sensations without judgement, has been increasingly applied to the treatment of addiction. By observing their pain and cravings objectively, for example, patients gain increased awareness of their responses to pain and their habits of opioid use. “They learn how to be with discomfort, whether emotional or physical, in a more compassionate way,” says Sarah Bowen, PhD, associate professor of psychology at Pacific University in Oregon. “And if your mind gives you a message like ‘Oh, I can’t handle that,’ to recognize that that’s a thought that might not be true.”
Bowen’s research is focused on Mindfulness-Based Relapse Prevention, which addresses the cravings associated with addiction. She has patients practice what she calls “urge surfing”: riding out a craving or urge rather than relying on a substance for immediate relief. “Craving will happen, so rather than fighting it, we look at understanding it better,” she says.
MORE differs from other forms of mindfulness-based therapy in that it integrates reappraisal and savoring training. Reappraisal is a technique often used in CBT in which patients learn to change negative thought patterns in order to reduce their emotional impact, while savoring helps to restructure the reward processes in the brain.
Mindfulness training not only helps patients to understand and gain control over their behavior in response to cravings and triggers like pain, says Garland, but also provides a means of pain relief. “We use mindfulness to zoom into pain and break it down into its subcomponents – feelings of heat or tightness or tingling – which reduces the impact that negative emotions have on pain processing in the brain.”
Eric Garland examines brain waves.
University of Utah
Powerful interventions
As the dangers of opioid addiction have become increasingly evident, some scientists are developing less addictive, non-opioid painkillers, but more trials are needed. Meanwhile, behavioral approaches to chronic pain relief have continued to gain traction, and researchers like Garland are probing the possibilities of integrative treatments to treat the addiction itself. Given that the number of people suffering from chronic pain and OUD have reached new heights during the COVID-19 pandemic, says Wachholtz, new treatment alternatives for patients caught in the relentless cycle of chronic pain and opioid misuse are sorely needed. “We’re trying to refine the techniques,” she says, “but we’re starting to realize just how powerful some of these mind-body interventions can be.”
Exactly 67 years ago, in 1955, a group of scientists and reporters gathered at the University of Michigan and waited with bated breath for Dr. Thomas Francis Jr., director of the school’s Poliomyelitis Vaccine Evaluation Center, to approach the podium. The group had gathered to hear the news that seemingly everyone in the country had been anticipating for the past two years – whether the vaccine for poliomyelitis, developed by Francis’s former student Jonas Salk, was effective in preventing the disease.
Polio, at that point, had become a household name. As the highly contagious virus swept through the United States, cities closed their schools, movie theaters, swimming pools, and even churches to stop the spread. For most, polio presented as a mild illness, and was usually completely asymptomatic – but for an unlucky few, the virus took hold of the central nervous system and caused permanent paralysis of muscles in the legs, arms, and even people’s diaphragms, rendering the person unable to walk and breathe. It wasn’t uncommon to hear reports of people – mostly children – who fell sick with a flu-like virus and then, just days later, were relegated to spend the rest of their lives in an iron lung.
For two years, researchers had been testing a vaccine that would hopefully be able to stop the spread of the virus and prevent the 45,000 infections each year that were keeping the nation in a chokehold. At the podium, Francis greeted the crowd and then proceeded to change the course of human history: The vaccine, he reported, was “safe, effective, and potent.” Widespread vaccination could begin in just a few weeks. The nightmare was over.
The road to success
Jonas Salk, a medical researcher and virologist who developed the vaccine with his own research team, would rightfully go down in history as the man who eradicated polio. (Today, wild poliovirus circulates in just two countries, Afghanistan and Pakistan – with only 140 cases reported in 2020.) But many people today forget that the widespread vaccination campaign that effectively ended wild polio across the globe would have never been possible without the human clinical trials that preceded it.
As with the COVID-19 vaccine, skepticism and misinformation around the polio vaccine abounded. But even more pervasive than the skepticism was fear. The consequences of polio had arguably never been more visible.
The road to human clinical trials – and the resulting vaccine – was a long one. In 1938, President Franklin Delano Roosevelt launched the National Foundation for Infantile Paralysis in order to raise funding for research and development of a polio vaccine. (Today, we know this organization as the March of Dimes.) A polio survivor himself, Roosevelt elevated awareness and prevention into the national spotlight, even more so than it had been previously. Raising funds for a safe and effective polio vaccine became a cornerstone of his presidency – and the funds raked in by his foundation went primarily to Salk to fund his research.
The Trials Begin
Salk’s vaccine, which included an inactivated (killed) polio virus, was promising – but now the researchers needed test subjects to make global vaccination a possibility. Because the aim of the vaccine was to prevent paralytic polio, researchers decided that they had to test the vaccine in the population that was most vulnerable to paralysis – young children. And, because the rate of paralysis was so low even among children, the team required many children to collect enough data. Francis, who led the trial to evaluate Salk’s vaccine, began the process of recruiting more than one million school-aged children between the ages of six and nine in 272 counties that had the highest incidence of the disease. The participants were nicknamed the “Polio Pioneers.”
Double-blind, placebo-based trials were considered the “gold standard” of epidemiological research back in Francis's day - and they remain the best approach we have today. These rigorous scientific studies are designed with two participant groups in mind. One group, called the test group, receives the experimental treatment (such as a vaccine); the other group, called the control, receives an inactive treatment known as a placebo. The researchers then compare the effects of the active treatment against the effects of the placebo, and every researcher is “blinded” as to which participants receive what treatment. That way, the results aren’t tainted by any possible biases.
But the study was controversial in that only some of the individual field trials at the county and state levels had a placebo group. Researchers described this as a “calculated risk,” meaning that while there were risks involved in giving the vaccine to a large number of children, the bigger risk was the potential paralysis or death that could come with being infected by polio. In all, just 200,000 children across the US received a placebo treatment, while an additional 725,000 children acted as observational controls – in other words, researchers monitored them for signs of infection, but did not give them any treatment.
As with the COVID-19 vaccine, skepticism and misinformation around the polio vaccine abounded. But even more pervasive than the skepticism was fear. President Roosevelt, who had made many public and televised appearances in a wheelchair, served as a perpetual reminder of the consequences of polio, as an infection at age 39 had rendered him permanently unable to walk. The consequences of polio had arguably never been more visible, and parents signed up their children in droves to participate in the study and offer them protection.
The Polio Pioneer Legacy
In a little less than a year, roughly half a million children received a dose of Salk’s polio vaccine. While plenty of children were hesitant to get the shot, many former participants still remember the fear surrounding the disease. One former participant, a Polio Pioneer named Debbie LaCrosse, writes of her experience: “There was no discussion, no listing of pros and cons. No amount of concern over possible side effects or other unknowns associated with a new vaccine could compare to the terrifying threat of polio.” For their participation, each kid received a certificate – and sometimes a pin – with the words “Polio Pioneer” emblazoned across the front.
When Francis announced the results of the trial on April 12, 1955, people did more than just breathe a sigh of relief – they openly celebrated, ringing church bells and flooding into the streets to embrace. Salk, who had become the face of the vaccine at that point, was instantly hailed as a national hero – and teachers around the country had their students to write him ‘thank you’ notes for his years of diligent work.
But while Salk went on to win national acclaim – even accepting the Presidential Medal of Freedom for his work on the polio vaccine in 1977 – his success was due in no small part to the children (and their parents) who took a risk in order to advance medical science. And that risk paid off: By the early 1960s, the yearly cases of polio in the United States had gone down to just 910. Where before the vaccine polio had caused around 15,000 cases of paralysis each year, only ten cases of paralysis were recorded in the entire country throughout the 1970s. And in 1979, the virus that once shuttered entire towns was declared officially eradicated in this country. Thanks to the efforts of these brave pioneers, the nation – along with the majority of the world – remains free of polio even today.