‘Amazing’ New Stem Cell Treatment for Neuropathy

By Pat Anson, Editor

Researchers at Duke University say an experimental stem cell therapy being tested on animals shows great potential to provide long-lasting pain relief for people suffering from diabetic neuropathy or other types of nerve damage.

In a study published in the Journal of Clinical Investigation, researchers said mice injected with a type of stem cell known as bone marrow stromal cells (BMSCs) were much less sensitive to nerve pain.

"This analgesic effect was amazing," said Ru-Rong Ji, PhD, a professor of anesthesiology and neurobiology in the Duke School of Medicine. "Normally, if you give an analgesic, you see pain relief for a few hours, at most a few days. But with bone marrow stem cells, after a single injection we saw pain relief over four to five weeks."

BMSCs are known to produce an array of healing factors and can be coaxed into forming other types of cells in the body. They are already being used to treat people with serious burns, inflammatory bowel disease, heart damage and stroke.  

"Based on these new results, we have the know-how and we can further engineer and improve the cells to maximize their beneficial effects," said Ji.

Researchers injected the mice with stem cells through a lumbar puncture, infusing them into the fluid that bathes the spinal cord.

The picture on the right shows how the injected stem cells (in red) migrated to the site of the nerve injury and were still present four weeks after treatment.

A molecule emitted from the injured nerve cells -- which has previously been linked to neuropathic pain – is believed to act as a “homing signal” and attract the stem cells.

Researchers measured levels of anti-inflammatory molecules in the mice and found that one in particular, TGF-β1, was present in higher amounts in the spinal fluid of the stem cell-treated animals.

TGF-β1 is a protein that is secreted by immune cells and is common throughout the body. Research has shown that people with chronic pain have too little TGF-β1.

courtesy duke university

Injecting TGF-β1 directly into spinal cord fluid provides pain relief, but only for a few hours, according to Ji. By contrast, bone marrow stromal cells stay on site for as much as three months after the infusion.

Ji’s research team is working to identify stem cells that produce more TGF-β1, as well as other types of pain relieving molecules. In addition to diabetic neuropathy, researchers believe stem cell therapy could also be used to treat pain from chemotherapy, surgical amputation, lower back pain and spinal cord injuries.

Nearly 26 million people in the United States have diabetes and about half have some form of neuropathy, according to the American Diabetes Association.  Diabetic peripheral neuropathy causes nerves to send out abnormal signals. Patients feel pain or loss of feeling in their toes, feet, legs, hands and arms. It may also include a persistent burning, tingling or prickling sensation. The condition can lead to injuries, chronic foot ulcers and even amputations.

Another recent animal study by researchers in the U.S. and South Korea found that diabetic rats given intramuscular injections of bone marrow stromal cells experienced both angiogenesis (blood vessel growth) and a restoration of the myelin sheath -- a protective covering over nerve cells damaged by neuropathy.

"Currently, the only treatment options available for DN (diabetic neuropathy) are palliative in nature, or are directed at slowing the progression of the disease by tightly controlling blood sugar levels," said Dr. John Sladek, Jr., Professor of Neurology, Pediatrics, and Neuroscience, Department of Neurology at the University of Colorado School of Medicine.

"This study offers new insight into the benefits of cell therapy as a possible treatment option for a disease that significantly diminishes quality of life for diabetic patients.”

The study is being published in the journal Cell Transplantation.

Cymbalta and Lyrica in Legal Battles

By Pat Anson, Editor

The makers of Cymbalta and Lyrica – two blockbuster drugs widely used to treat fibromyalgia and other chronic pain conditions – face legal battles this summer that could potentially cost the companies billions of dollars.

In London, a court case begins next week on Pfizer’s efforts to keep doctors in the U.K. from prescribing pregabalin – a cheaper generic version of Lyrica.

And in Los Angeles, a federal judge this week ordered Eli Lilly to face claims in lawsuits alleging that the company misled consumers about the side effects of withdrawal from Cymbalta.

Over 5,000 patients have filed suit against Lilly claiming that Cymbalta caused “brain zaps” – electric shocking sensations – as well as nausea, vomiting and insomnia when they stopped taking the drug.  The first two cases will be heard in August.

“The withdrawal symptoms from Cymbalta were hell,” wrote Crystal Lindell, a Pain News Network columnist in a recent article.

“Less than a week after my last pill, I was getting so dizzy that I seriously thought I had a new disease. Then, there was this thing called the brain zaps that I didn’t understand until they happened to me. In short, it literally felt like my brain was being, well, zapped by electricity. There was also nausea and vertigo and just an overall feeling of falling off a skyscraper.” 

Several readers shared their own experiences with Cymbalta.

“My neurologist put me on Cymbalta, I took 2 pills, I thought my head was going to explode,” wrote Judy Dunn.

“I suffered from 6 weeks of vertigo, nausea, dizziness, and MASSIVE headaches,” said Andy, who was prescribed Cymbalta to treat depression. “I will never take Cymbalta again. EVER.”

“While on the drug I did get a better mood and it helped a lot, but it raised my blood pressure and I was shaky and jittery. I also went through the brain ZAPS!!” wrote Candra Clark.

“We believe in our defenses to these claims and we will continue to defend Lilly vigorously,” Scott MacGregor, a Lilly spokesman told Bloomberg Business.

Cymbalta generated annual sales of $5 billion for Lilly until its patent expired in 2013 and cheaper generic versions of Doluxetine became available.

Lyrica Legal Battle

Like Cymbalta, Lyrica wasn’t originally developed to treat pain. It was used as a treatment for anxiety and epilepsy until drug maker Pfizer realized it could also be effective for fibromyalgia and neuropathic pain.

Pfizer’s patent on Lyrica for epilepsy and anxiety expired last year, but its secondary patent for pain is good until July of 2017 – and that is the essence of its legal fight in the U.K.

Rival drug makers started making pregabalin – the generic version of Lyrica – when its original patent expired. But it didn’t take long for doctors to also start prescribing pregabalin for pain.

According to Pharmalot, about 80% of all U.K. patients on pregabalin are using it to treat pain and Pfizer has launched an aggressive campaign to stop that. Last year the company wrote an unusual letter to physician groups in the U.K. warning them that prescribing pregabalin for pain was a violation of its patent.

“Pfizer believes the supply of generic pregabalin for use in the treatment of pain whilst the pain patent remains in force in the U.K. would infringe Pfizer’s patent rights,” the company said in the letter.

The Royal College of Physicians, which represents 29,000 U.K. doctors, responded with a statement of its own.

“Pregabalin is a useful drug for many patients and, given the current financial pressures the NHS (Britain’s National Health Service) is under, it is disappointing that a pharmaceutical company has made a move that will, potentially, prevent some patients from getting access to it,” a spokesman said.

The NHS has since issued guidance to doctors telling them to use the brand name Lyrica when prescribing pregabalin for pain “so far as reasonably possible.” Pfizer is seeking a stronger statement from the British High Court.

Ironically, Pfizer paid $2.3 billion dollars in 2009 to settle criminal and civil charges in the U.S. for the “off-label” marketing of Lyrica and other medications – the very sort of off-label use it is trying to stop in the U.K.

Lyrica remains one of Pfizer’s top selling drugs, generating $5.1 billion in revenue in 2014.  

New Drugs Could Relieve Neuropathy Pain

By Pat Anson, Editor

After more than a decade of study, researchers at Boston Children’s Hospital are close to developing a new class of non-narcotic drugs that relieve chronic nerve pain by targeting a protein that enhances pain and inflammation.

Their findings, reported in the journal Neuron, could lead to new treatments for diabetic peripheral neuropathy, post-herpetic neuralgia, and inflammatory diseases like rheumatoid arthritis. Current treatments provide meaningful pain relief in only about 15 percent of patients.

"Most pain medications that have been tested in the past decade have failed in Phase II human trials despite performing well in animal models," notes Clifford Woolf, MD, PhD, director of Boston Children's F.M. Kirby Neurobiology Center and a co-senior investigator on the study. "Here, we used human genetic findings to guide our search from the beginning."

Previous research by Woolf and his colleagues found that people with variants of the gene for GTP cyclohydrolase (GCH1) -- about 2 percent of the population -- are at markedly lower risk for chronic pain. GCH1 is needed to synthesize the protein tetrahydrobiopterin (BH4), and people with GCH1 variants produced less BH4 after a nerve injury. This suggested that BH4 regulates pain sensitivity.

To test their theory, researchers took a "reverse engineering" approach in genetic experiments on mice.  First they showed that mice with severed sensory nerves produce excess BH4, created by the injured nerve cells and by macrophages-- immune cells that infiltrate damaged nerves and inflamed tissue.

Mice that were genetically engineered to make excess BH4 had heightened pain sensitivity even when they were uninjured. Conversely, mice that were genetically unable to produce BH4 had lower pain hypersensitivity after a peripheral nerve injury.

"We then asked, if we could reduce production of BH4 using a drug, could we bring about reduction of pain?" said Alban Latremoliere, PhD, also of Boston Children's Kirby Center, who led the current study.

The answer was yes. The researchers blocked BH4 production using a specifically designed drug that targets sepiapterin reductase (SPR), a key enzyme that makes BH4. The drug reduced the pain hypersensitivity induced by nerve injury and without any detectable side effects.

Because BH4 plays an important role in the brain and blood vessels, the goal of any treatment would be to dial down excessive BH4 production, but not eliminate it entirely. Latremoliere showed that blocking SPR still allowed minimal BH4 production through a separate pathway and reduced pain without causing neural or cardiovascular side effects.

"Our findings suggest that SPR inhibition is a viable approach to reducing clinical pain hypersensitivity," says Woolf. "They also show that human genetics can lead us to novel disease pathways that we can probe mechanistically in animal models, leading us to the most suitable targets for human drug development."

Vegan Diet Reduces Neuropathy Pain

By Pat Anson, Editor

A vegetarian diet coupled with a daily vitamin B12 supplement significantly reduced pain and improved the quality of life of people with diabetic neuropathy, according to the findings of a small study published in Nutrition & Diabetes. Participants also lost an average of 14 pounds.

Nearly 26 million people in the United States have diabetes and about half have some form of neuropathy, according to the American Diabetes Association.  Diabetic peripheral neuropathy causes nerves to send out abnormal signals. Patients feel burning, tingling or prickling sensations in their toes, feet, legs, hands and arms.

Many drugs used to treat neuropathic pain, such as Neurontin and Lyrica, often don’t work or have unpleasant side effects.

Researchers at California State University, East Bay, and the George Washington University School of Medicine put 17 adults on a low-fat vegan diet that focused on vegetables, fruits, grains and legumes. Typical meals included oatmeal with raisins, pasta with marinara sauce, vegetable stir-fry with rice, and lentil stew.

Participants also took a daily vitamin B12 supplement, as did a control group that did not alter its diet.

After 20 weeks, patients on the vegan diet not only had less neuropathic pain, they had lower blood pressure and cholesterol levels and had lost weight.

"A dietary intervention reduces the pain associated with diabetic neuropathy, apparently by improving insulin resistance" said Neal Barnard, MD, president of the Physicians Committee for Responsible Medicine at CSU East Bay.

Researchers also noted there was significant improvement in pain and other symptoms in the control group.  The magnitude of the improvement suggests that the B12 supplement, intended to serve as a placebo, may have had real effects in both groups.

One in three children born in the U.S. in 2000 will develop diabetes at some point in his or her life. The average lifetime cost to treat type 2 diabetes is $85,200, half of which is spent on diabetes complications.

"The dietary intervention is easy to prescribe and easy to follow," says Cameron Wells, a registered dietician and acting director of nutrition education for the Physicians Committee. "Steel-cut oats, leafy greens, and lentils are widely available at most food markets and fit well into most budgets."

My Life with Trigeminal Neuralgia

By Pat Akerberg

Most of us don’t focus on the idea of pain until we find ourselves in it for one reason or another.  We just know that we’re glad when it’s gone. 

But what if it doesn’t go away? 

Challenging conditions occur for some of us that catapult us into a life of chronic, intractable pain.  You know you are one of the unlucky ones when meetings with doctors end with statements like:

“There is nothing we can do.”

“You’ll just have to live with it.”

“It’s all in your head.”

That last statement is the one that literally began my life-altering journey with pain. An outgoing, upbeat owner of a thriving consulting practice, I was on a business trip enjoying dinner with a favorite client six years ago.  My meal started with a typical salad.  By the second bite, I was writhing through volleys of shocking pain shooting through the roots of my teeth on my left side.

PAT AKERBERG

I later learned that this neurological disorder of the 5th cranial nerve was trigeminal neuralgia -- also known as the “suicide disease” or “worst pain known to mankind.”  I had to cut my trip short and fly home to see my dentist, pronto.  Little did I know then that this event would mark the end my of work life, one of the growing list of ongoing losses for me to grieve.

I was both unfortunate and fortunate during my short search to find a proper diagnosis, one that often takes many months or years to receive.  Unfortunate in that trigeminal neuralgia (TN) is so rare, the cause is unknown, treatments do not offer a permanent cure, and sometimes create more pain issues.  Fortunate in that I escaped the needless root canals or extractions that most are subjected to prior to an accurate diagnosis.

Research became my middle name as I sought to learn everything that I could to get my problem “fixed.” I was driven to get back to my career and serve my clients.  Research collectively pointed to an invasive brain surgery done by a neurosurgeon.  It seemed to have the best odds for a cure, with the least chance of further damage to the nerve. 

Unfortunately, permanent nerve damage is exactly what occurred.  Imagine my concern when I awoke from surgery with my face immovable; frozen like a block of concrete, numb with pulling sensations, and the stabbing pain in my teeth now constant. 

The neurosurgeon who held out a sure cure quickly distanced himself -- perceiving me as “too anxious” about the devastating impairments and pain frequency.  With dispatch and without explanation, my case was closed.    

Left on my own to seek out answers and help, I pursued consultations with several other leading TN experts.  With honesty and compassion, each one delivered the same bad news: medicine and science have not caught up with how to effectively treat a damaged trigeminal nerve.  Advising against further procedures, my lifetime membership into the intractable pain club was validated. 

“Invisible” Pain

Being a co-habitant with an intrusive bully like intractable pain has been all consuming.  Any illusions I had of control have been shattered. 

There’s also an invisible aspect to my pain that can create issues with believability.

Most people are unaware of orphan diseases like trigeminal neuralgia, and have little understanding and compassion towards those who have them. 

Family members, who are turned into caregivers overnight, scramble to figure out how to relate to a frightening pain condition.  Many close friends eventually drift away when you don’t get better, are unable to keep up, or cancel plans too often. And busy medical professionals can skeptically question what they cannot see or touch.  

That’s partly because we are so often judged by how we look versus what we say. If we don’t look sick or in pain, then the erroneous assumption follows that we can’t be that bad.  But we can be! 

When I report that I am unable to chew solid food (eat out), talk, smile, laugh (socialize), move my face or have anything touch it (brush teeth, take walks, exercise) without triggering unbearable facial pain; most people can’t square such an unthinkable loss of natural life functions with how I appear to them.

I agree. It is hard to fathom, yet with neuropathic pain disorders like TN, simple things that normally don’t cause pain now do. Combine those quality of life diminishments and misconceptions with disabling pain and the ingredients for a lonely, isolated existence can’t be denied. 

Often I feel as if I am living in an inescapable bubble, missing out while the rest of the world goes by without me. It takes tremendous fortitude daily for me to counter those negative effects in my life with meaningful ones.  Some days are more successful than others. 

Like most who suffer with chronic pain, the search for any kind of relief becomes a way to keep hope alive.  In the meantime, I do find it helpful to post, blog, and reach out to connect with people like myself whenever I can.  It reminds me that I am not alone in this often debilitating journey.

Pat Akerberg lives in Florida. Pat is a member of the TNA Facial Pain Association and serves as a moderator for their online support forum.

Pat is also a supporter of the Trigeminal Neuralgia Research Foundation.

Pain News Network invites other readers to share their stories with us. 

Send them to:  editor@PainNewsNetwork.org.

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represents the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.

Two Drug Combo Relieves Neuropathy Pain

By Pat Anson, Editor

British researchers say a combination of two widely used drugs – an antidepressant and an opioid – can significantly relieve pain and other symptoms caused by neuropathy.

In a study published in the journal PAIN, researchers at Queens University say combining the painkiller morphine with the antidepressant nortriptyline relieved chronic neuropathic pain in nearly 90 percent of patients – significantly better than when either drug is used alone.

"Morphine and nortriptyline are excellent candidates for pain management because of the extensive research conducted on them, their low cost, and widespread availability all over the world," said Ian Gilron, MD, a professor in Queen's School of Medicine and anesthesiologist at Kingston General Hospital.

"Current neuropathic pain treatments are ineffective or intolerable for many sufferers so this new evidence supporting the morphine-nortriptyline combination is important news for patients."

Nortriptyline, an antidepressant sold under the brand names Aventyl and Pamelor, is already being used to treat pain in the arms and legs caused by multiple sclerosis. Morphine has long been used to treat both acute and chronic pain.

Neuropathic pain is characterized by tingling or burning sensations that develop as result of nerve damage caused by conditions such as shingles, diabetes, amputation, inflammation, and cancer. About 8% of adults worldwide suffer from neuropathy. Many drugs used to treat neuropathic pain, such as Neurontin and Lyrica, often don’t work or have unpleasant side effects.

In the double-blind, randomized study, 52 neuropathy patients were given a choice of trying every one of three treatments: morphine alone, nortriptyline alone, and a combination of the two drugs over six-week treatment periods. Patients were asked to record their pain levels and side effects during each treatment.

The average daily pain before treatment was 5.6, measured using a rating scale from 0-10. Average daily pain dropped to 2.6 when patients received the two drug combination. Patients taking nortriptyline and morphine alone rated their pain at 3.1 and 3.4, respectively.

Researchers said that common side effects for both drugs, which include constipation and dry mouth, did not worsen with the combined treatment.

"It's important to remember that we don't want to completely eliminate patients' ability to sense pain as it's a warning system for us, but we do want to find the right balance of pain relief and drug side effects," said Gilron

Nortriptyline and morphine are currently not available in a combined formulation. According to the Mayo Clinic, using the two drugs together is usually not recommended because they both cause sedation.

Can Viagra Treat Diabetic Neuropathy?

By Pat Anson, Editor

An experimental animal study suggest that sildenafil, an erectile dysfunction drug commonly known by the brand name Viagra, may be effective in relieving symptoms of peripheral neuropathy in men with long-term diabetes. The study is published online in PLOS ONE.

Diabetic peripheral neuropathy causes nerves to send out abnormal signals. Patients feel pain, tingling or burning sensation in their toes, feet, legs, hands or arms. Nearly 26 million people in the U.S. have diabetes and about half have some form of neuropathy, according to the American Diabetes Association. 

In previous animal studies, researchers at Henry Ford Hospital in Detroit found that sildenafil improved blood supply to the sciatic nerve and relieved symptoms of neuropathy. However, it was not known if this therapeutic effect held true for long-term peripheral neuropathy, because the diabetic mice used in the previous experiments were relatively young - 16 weeks old.

"Generally, young diabetic animals with an early stage of peripheral neuropathy are used to investigate various drug treatments," said Lei Wang, MD, the Henry Ford neuroscientist who led the research. "But patients with diabetes who are enrolled in clinical trials often are older and have advanced peripheral neuropathy.

To mimic clinical trials in which diabetes patients have advanced peripheral neuropathy, Wang and his colleagues chose male mice with type II diabetes that were 36 weeks old, roughly equivalent to middle age in humans.

In one group, 15 diabetic mice were treated with an oral dose of sildenafil/Viagra every day for eight weeks. A control group of 15 age-matched diabetic mice were treated daily with the same amount of saline.

Researchers found after a battery of nerve and function tests on both groups of mice that sildenafil markedly improved sensory function after six weeks of treatment.

“Treatment of diabetic mice at age 36 weeks with sildenafil significantly increased functional blood vessels and regional blood flow in the sciatic nerve,” said Wang. “Functional analysis showed that the sildenafil treatment considerably improved motor and sensory conduction velocities in the sciatic nerve and peripheral thermal stimulus sensitivity compared with the saline treatment.

“These findings provide new insights into mechanisms underlying the neurological dysfunction of long term diabetic peripheral neuropathy and may lead to the development of a sildenafil therapy for long term diabetic peripheral neuropathy.”

Since becoming available in 1998, Viagra has been found to relieve several other conditions beside erectile dysfunction, such as jet lag and altitude sickness. Some professional athletes also believe that Viagra enhances their performance by opening their blood vessels and increasing oxygen supply to their muscles.

Lyrica Fails in Study of Juveniles with Fibromyalgia

By Pat Anson, Editor

Lyrica, a blockbuster drug widely prescribed to treat chronic pain in adults, works no better than a placebo in treating juveniles with fibromyalgia, according to the results of a new study released by Pfizer (PFE). Lyrica is Pfizer’s top selling drug with annual worldwide sales of over $5 billion.

The double-blind Phase IV trial was conducted to fulfill a post-marketing study required by the Food and Drug Administration after Lyrica was approved for the management of fibromyalgia in adults in 2007. The generic name of Lyrica is pregabalin, which was originally developed as an anti-epileptic drug.

“The primary endpoint of the study was not achieved as there was not a statistically significant difference between pregabalin and placebo in mean pain score,” Pfizer said in a statement.

A total of 107 adolescents (ages 12-17 years) were enrolled in the 15-week study at multiple centers across the U.S., Europe and Asia. It was the first large study on the efficacy and safety of Lyrica in juveniles with fibromyalgia.

The National Institutes of Health estimates that about 5 million Americans suffer from fibromyalgia, a poorly understood disorder characterized by deep tissue pain, fatigue, headaches, mood swings and insomnia.

In the study, Lyrica was administered twice daily, starting at 75 mg/day and then increasing to up to 450 mg/day, depending on the tolerability and response of the patient. The most common side effects in the study were dizziness, nausea, headache, increased weight and fatigue. Many other patients who take Lyrica complain of similar symptoms.

"Pfizer is committed to better understanding the full clinical profile of our approved medicines in pediatric and adolescent patients. This study advances the understanding of this patient population," said Steve Romano, MD, senior vice president of Global Medicines Development for Pfizer. "These results do not change the established benefit of Lyrica for its approved indications, including fibromyalgia in adults."

In addition to fibromyalgia, Lyrica is approved by the FDA to treat chronic pain associated with epilepsy, shingles, diabetic peripheral neuropathy, and spinal cord injury. The drug is also prescribed “off label” to treat lumbar spinal stenosis, the most common type of lower back pain in older adults.

Gene Therapy Lessens Pain of Diabetic Neuropathy (VIDEO)

By Pat Anson, Editor

An experimental gene therapy reduces pain and other symptoms by over 50 percent in patients with diabetic peripheral neuropathy, according to a new study at Northwestern University.

Nearly 26 million people in the United States have diabetes and about half have some form of neuropathy, according to the American Diabetes Association.  Diabetic peripheral neuropathy (DPN) causes nerves to send out abnormal signals. Patients feel pain or loss of feeling in their toes, feet, legs, hands and arms. It may also include a persistent burning, tingling or prickling sensation. The condition can lead to injuries, chronic foot ulcers and even amputations.

Keith Wenckowski, who has type-one diabetes, says it felt “like walking on glass” when he walked barefoot in sand.   

Wenckowski and 83 other participants in the Northwestern study received two low doses of a non-viral gene therapy called VM202. They went to a clinic twice in a two-week period for a series of injections into their calf muscles and lower legs. Some received injections of a saline placebo, others a low dose of the therapy and others a higher dose.

"Those who received the therapy reported more than a 50 percent reduction in their symptoms and virtually no side effects," said Dr. Jack Kessler, lead author of the study. "Not only did it improve their pain, it also improved their ability to perceive a very, very light touch."

After three months, patients in the low-dose group experienced a significant reduction in pain compared to the placebo group. The effect persisted at six and nine months in the low-dose group.

"I can now go to a beach and walk on the sand without feeling like I am walking on glass," says Wenckowski, more than a year after receiving the therapy. "I am hoping the effects I am feeling do not cease."

VM202 contains the human hepatocyte growth factor (HGF) gene. Growth factor is a naturally occurring protein in the body that acts on nerve cell to keep them alive, healthy and functioning. Future studies will investigate if the therapy can actually regenerate damaged nerves and reverse the neuropathy.

Patients with the most extreme form of the DPN feel intense pain with a slight graze or touch. The pain can interfere with daily activities, sleep, mood and can diminish quality of life. Many drugs used to treat DPN, such as Neurontin and Lyrica, either don’t work or have unpleasant side effects.

"We are hoping that the treatment will increase the local production of hepatocyte growth factor to help regenerate nerves and grow new blood vessels and therefore reduce the pain," said Senda Ajroud-Driss, MD, an attending physician at Northwestern Memorial Hospital and an author of the study.

"We found that the patients who received the low dose had a better reduction in pain than the people who received the high dose or the placebo. Side effects were limited to injection site reaction."

The results of this Phase II, double-blind, placebo-controlled study are being published in the journal Annals of Clinical and Translation Neurology.A future, much larger Phase III study will soon be underway.

"Right now there is no medication that can reverse neuropathy," Kessler said. "Our goal is to develop a treatment. If we can show with more patients that this is a very real phenomenon, then we can show we have not only improved the symptoms of the disease, namely the pain, but we have actually improved function."