Kelly, a case manager for an insurance company, spent years battling both migraines and Crohn's, a disease in which the immune system attacks the intestines.
For many people, like Kelly, a stronger electric boost to the vagus nerve could be life-changing.
After she had her large intestine removed, her body couldn't absorb migraine medication. Last year, about twice a month, she endured migraines so bad she couldn't function. "It would go up to a ten, and I would rock, wait it out," she said. The pain might last for three days.
Then her neurologist showed her a new device, gammaCore, that tames migraines by stimulating a nerve—not medication. "I don't have to put a chemical in my body," she said. "I was thrilled."
At first, Kelly used the device at the onset of a migraine, applying electricity to her pulse at the front of her neck for six minutes. The pain peaked at about half the usual intensity--low enough, she said, that she could go to work. Four months ago, she began using the device for two minutes each night as prevention, and she hasn't had a serious migraine since.
The Department of Defense and Veterans Administration now offer gammaCore to patients, but it hasn't yet been approved by Medicare, Medicaid, or most insurers. A month of therapy costs $600 before insurance or a generous financial assistance program kicks in.
A patient uses gammaCore, a non invasive vagal nerve stimulator device that was FDA approved in November 2018, to treat her migraine.
(Photo captured from a patient video at gammacore.com)
If the poet Walt Whitman wrote "I Sing The Body Electric" today, he might get specific and point to the vagus nerve, a bundle of fibers that run from the brainstem down the neck to the heart and gut. Singing stimulates it—and for many people, like Kelly, a stronger electric boost to the nerve could be life-changing.
The mind-body connection isn't just an idea — the vagus nerve literally carries signals from the mind to the body and back. It may explain the link between childhood trauma and illnesses such as chronic pain and headaches in adults. "How is it possible that a psychological event causes pain years later?" asked Peter Staats, co-founder of electroCore, which has won approval for its new device from the Food and Drug Administration (FDA) for both migraine and cluster headaches. "There has to be a mind-body interface, and that is the vagus nerve," he said.
Scientists knew that this nerve controlled your heart rate and blood pressure, but in the past decade it has been linked to both pain and the immune system.
"Everything is gated through the vagus -- problems with the gut, the heart, and the lungs," said Chris Wilson, a researcher at Loma Linda University, in California. Wilson is studying how vagus nerve stimulation (VNS) could help pre-term babies who develop lung infections. "Nearly every one of our chronic diseases, including cancer, Alzheimer's, Parkinson's, chronic arthritis and rheumatoid arthritis, and depression and chronic pain…could benefit from an appropriate stimulator," he said.
It's unfortunate that Kelly got her device only after her large intestine was gone. SetPoint Medical, a privately held California company founded to develop electronic treatments for chronic autoimmune diseases, has announced early positive results with VNS for both Crohn's and rheumatoid arthritis.
As SetPoint's chief medical officer, David Chernoff, put it, "We're hacking into the nervous system to activate a system that is already there," an approach that, he said, could work "on many diseases that are pain- and inflammation-based." Inflammation plays a role in much modern illness, including depression and obesity. The FDA already has approved VNS for both, using surgically implanted devices similar to pacemakers. (GammaCore is external.)
The history of VNS implants goes back to 1997, when the FDA approved one for treating epilepsy and researchers noticed that it rapidly lifted depression in epileptic patients. By 2005, the agency had approved an implant for treatment-resistant depression. (Insurance companies declined to reimburse the approach and it didn't take off, but that might change: in February, the Center for Medicare and Medicaid Services asked for more data to evaluate coverage.) In 2015, the FDA approved an implant in the abdomen to regulate appetite signals and help obese people lose weight.
The link to inflammation had emerged a decade earlier, when researchers at the Feinstein Institute for Medical Research, in Manhasset, New York, demonstrated that stimulating the nerve with electricity in rats suppressed the production of cytokines, a signaling protein important in the immune system. The researchers developed a concept of a hard-wired pathway, through the vagus nerve, between the immune and nervous system. That pathway, they argued, regulates inflammation. While other researchers argue that VNS is helpful by other routes, there is clear evidence that, one way or another, it does affect immunity.
At the same time, investors are seeking alternatives to drugs.
The Feinstein rat research concluded that it took only a minute a day of stimulation and tiny amounts of energy to activate an anti-inflammatory reflex. This means you can use devices "the size of a coffee bean," said Chernoff, much less clunky than current pacemakers—and advances in electronic technology are making them possible.
At the same time, investors are seeking alternatives to drugs. "There's been a push back on drug pricing," noted Lisa Rhoads, a managing director at Easton Capital Investment Group, in New York, which supported electroCore, "and so many unintended consequences."
In 2016, the U.S. National Institutes of Health began pumping money into relevant research, in a program called "Stimulating Peripheral Activity to Relieve Conditions," which focuses on "understanding peripheral nerves — nerves that connect the brain and spinal cord to the rest of the body — and how their electrical signals control internal organ function."
GlaxoSmithKline formed Galvani Bioelectronics with Google to study miniature implants. It had already invested in Action Potential Venture Capital, in Cambridge, Massachusetts, which holds SetPoint and seven other companies "that are all targeting a nerve to treat a chronic disease," noted partner Imran Eba. "I see a future in which bioelectronics medicine is competing directly with drugs," he said.
Treating the body with electricity could bring more ease and lower costs. Many people with serious auto-immune disease, for example, have to inject themselves with drugs that cost $60,000 a year. SetPoint's implant would cost less and only need charging once a week, using a charger worn around the neck, Chernoff said. The company receives notices remotely and can monitor compliance.
Implants also allow the treatment to target a nerve precisely, which could be important with Parkinson's, chronic pain, and depression, observed James Cavuoto, editor and publisher of Neurotech Reports. They may also allow for more fine-turning. "In general, the industry is looking for signals, biomarkers that indicate when is the right time to turn on and turn off the stimulation. It could dramatically increase the effectiveness of the therapy and conserve battery life," he said.
Eventually, external devices could receive data from biomarkers as well. "It could be something you wear on your wrist," Cavuoto noted. Bluetooth-enabled devices could communicate with phones or laptops for data capture. External devices don't require surgery and put the patient in charge. "In the future you'll see more customer specification: Give the patient a tablet or phone app that lets them track and modify their parameters, within a range. With digital devices we have an enormous capability to customize therapies and collect data and get feedback that can be fed back to the clinician," Cavuoto said.
Slow deep breathing, the traditional mind-body intervention, is "like watching Little League. What we're doing is Major League."
It's even possible to stimulate the vagus through the ear, where one branch of the bundle of fibers begins. In a fetus, the tissue that becomes the ear is also part of the vagus nerve, and that one bit remains. "It's the same point as the acupuncture point," explained Mark George, a psychiatrist and pioneer researcher in depression at Medical University of South Carolina in Charleston. "Acupuncture figured out years ago by trial and error what we're just learning about now."
Slow deep breathing, the traditional mind-body intervention, also affects the vagus nerve in positive ways, but gently. "That's like watching Little League," Staats, the co-founder of electroCore, said. "What we're doing is Major League."
In ten years, researcher Wilson suggested, you could be wearing "a little ear cuff" that monitors your basic autonomic tone, a heart-attack risk measure governed in part by the vagus nerve. If your tone looked iffy, the stimulator would intervene, he said, "and improve your mood, cognition, and health."
In the meantime, we can take some long slow breaths, read Whitman, and sing.
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.
Here are the promising studies covered in this week's Friday Five:
- Research on a "smart" bandage for wounds
- A breakthrough in fighting inflammation
- The pros and cons of a new drug for Alzheimer's
- Benefits of the Mediterranean diet - with a twist
- How to recycle a plastic that was un-recyclable
Sexually transmitted infections (STIs) are surging across the U.S. to 2.5 million cases in 2021 according to preliminary data from the CDC. A new prevention and treatment strategy now in clinical trials may provide a way to get a handle on them.
It's easy to overlook the soaring rates of gonorrhea, chlamydia, and syphilis because most of those infections have few or no symptoms and can be identified only through testing. But left untreated, they can lead to serious damage to nerves and tissue, resulting in infertility, blindness, and dementia. Infants developing in utero are particularly vulnerable.
Covid-19 played havoc with regular medical treatment and preventive care for many health problems, including STIs. After formal lockdowns ended, many people gradually became more socially engaged, with increases in sexual activity, and may have prioritized these activities over getting back in touch with their doctors.
A second blow to controlling STIs is that family planning clinics are closing left and right because of the Dobbs decision and legislation in many states that curtailed access to an abortion. Discussion has focused on abortion, but those same clinics also play a vital role in the diagnosis and treatment of STIs.
Routine public health is the neglected stepchild of medicine. It is called upon in times of crisis but as that crisis resolves, funding dries up. Labs have atrophied and personnel have been redirected to Covid, “so access to routine screening for STIs has been decimated,” says Jennifer Mahn, director of sexual and clinical health with the National Coalition of STD Directors.
A preview of what we likely are facing comes from Iowa. In 2017, the state legislature restricted funding to family health clinics in four counties, which closed their doors. A year later the statewide rate of gonorrhea skyrocketed from 83 to 153.7 cases per 100,000 people. “Iowa counties with clinic closures had a significantly larger increase,” according to a study published in JAMA. That scenario likely is playing out in countless other regions where access to sexual health care is shrinking; it will be many months before we have the data to know for sure.
A decades-old antibiotic finds a new purpose
Using drugs to protect against HIV, either as post exposure prophylaxis (PEP) or pre-exposure prophylaxis (PrEP), has proven to be quite successful. Researchers wondered if the same approach might be applied to other STIs. They focused on doxycycline, or doxy for short. One of the most commonly prescribed antibiotics in the U.S., it’s a member of the tetracycline family that has been on the market since 1967. It is so safe that it’s used to treat acne.
Two small studies using doxy suggested that it could work to prevent STIs. A handful of clinical trials by different researchers and funding sources set out to generate the additional evidence needed to prove their hypothesis and change the standard of care.
Senior researcher Victor Omollo, with the Kenya Medical Research Institute, noted, “These are prevention interventions that women can control on their own without having to seek or get consent from another person,” as is the case with condom use.
The first with results is the DoxyPEP study, conducted at two sexual health clinics in San Francisco and Seattle. It drew from a mix of transgender women and men who have sex with men, who had at least one diagnosed STI over the last year. The researchers divided the participants into two groups: one with people who were already HIV-positive and engaged in care, while the other group consisted of people who were on PrEP to prevent infection with HIV. For the active part of the study, a subset of the participants received doxy, and the rest of the participants did not.
The researchers intentionally chose to do the study in a population at the highest risk of having STIs, who were very health oriented, and “who were getting screened every three months or so as part of their PrEP program or their HIV care program,” says Connie Celum, a senior researcher at the University of Washington on the study.
Each member of the active group was given a supply of doxy and asked to take two pills within 72 hours of having sex where a condom was not used. The study was supposed to run for two years but, in May, it stopped halfway through, when a safety monitoring board looked at the data and recommended that it would be unethical to continue depriving the control group of the drug’s benefits.
Celum presented these preliminary results from the DoxyPEP study in July at the International AIDS Conference in Montreal. “We saw about a 56 percent reduction in gonorrhea, about 80 percent reduction in chlamydia and syphilis, so very significant reductions, and this is on a per quarter basis,” she told a later webinar.
In Kenya, another study is following a group of cisgender women who are taking the same two-pill regimen to prevent HIV, and the data from this research should become available in 2023. Senior researcher Victor Omollo, with the Kenya Medical Research Institute, noted that “these are prevention interventions that women can control on their own without having to seek or get consent from another person,” as is the case with condom use, another effective prevention tool.
Antibiotic resistance is a potentially big concern. About 25 percent of gonorrhea strains circulating in the U.S. are resistant to the tetracycline class of drugs, including doxy; rates are higher elsewhere. But resistance often is a matter of degree and can be overcome with a larger or longer dose of the drug, or perhaps with a switch to another drug or a two-drug combination.
Research has shown that an established bacterial infection is more difficult to treat because it is part of a biofilm, which can leave only a small portion or perhaps none of the cell surface exposed to a drug. But a new infection, even one where the bacteria is resistant to a drug, might still be vulnerable to that drug if it's used before the bacterial biofilm can be established. Preliminary data suggests that may be the case with doxyPEP and drug resistant gonorrhea; some but not all new drug resistant infections might be thwarted if they’re treated early enough.
“There are some tradeoffs” to these interventions, Celum says, and people may disagree on the cost of increased resistance balanced against the benefits of treating the STIs and reducing their spread within the community.
Resistance does not seem to be an issue yet for chlamydia and syphilis even though doxy has been a recommended treatment for decades, but a remaining question is whether broader use of doxy will directly worsen antibiotic resistance in gonorrhea, or promote it in other STIs. And how will it affect the gut microbiome?
In addition, Celum notes that we need to understand whether doxy will generate mutations in other bacteria that might contribute to drug resistance for gonorrhea, chlamydia or syphilis. The studies underway aim to provide data to answer these questions.
“There are some tradeoffs” to these interventions, Celum says, and people may disagree on the cost of increased resistance balanced against the benefits of treating the STIs and reducing their spread within the community. That might affect doctors' willingness to prescribe the drug.
Turning research into action
The CDC makes policy recommendations for prevention services such as taking doxy, requiring some and leaving others optional. Celum says the CDC will be reviewing information from her trial at a meeting in December, but probably will wait until that study is published before making recommendations, likely in 2023. The San Francisco Department of Public Health issued its own guidance on October 20th and anecdotally, some doctors around the country are beginning to issue prescriptions for doxy to select patients.
About half of new STIs occur in young people ages 15 to 24, a group that is least likely to regularly see a doctor. And sexual health remains a great taboo for many people who don't want such information on their health record for prying parents, employers or neighbors to find out.
“People will go out of their way and travel extensive distances just to avoid that,” says Mahn, the National Coalition director. “People identify locations where they feel safe, where they feel welcome, where they don't feel judged,” Mahn explains, such as community and family planning clinics. They understand those issues and have fees that vary depending on a person’s ability to pay.
Given that these clinics already are understaffed and underfunded, they will be hard pressed to expand services covering the labor intensive testing and monitoring of a doxyPEP regimen. Sexual health clinics don't even have a separate line item in the federal budget for health. That is something the National Association of STI Directors is pushing for in D.C.
DoxyPEP isn't a panacea, and it isn't for everyone. “We really want to try to reach that population who is most likely going to have an STI in the next year,” says Celum, “Because that's where you are going to have the biggest impact.”