The cost of many drugs to treat multiple sclerosis (MS) can add up to tens of thousands of dollars annually. But researchers may have found a low-cost alternative that is even more effective at treating the autoimmune disease.
Biochemists at the University of Wisconsin-Madison have discovered a promising vitamin D treatment that can halt — and even reverse — the course of the disease in laboratory mice.
Mice that exhibit MS symptoms were given a single dose of calcitriol, the active hormonal form of vitamin D, along with vitamin D supplements in their diet.
“All of the animals just got better and better, and the longer we watched them, the more neurological function they regained,” says biochemistry professor Colleen Hayes, who led the study that was published in the Journal of Neuroimmunology.
MS is a chronic disease which attacks the body’s central nervous system and destroys the myelin sheath that protects nerve cells. An estimated 400,000 Americans have the disease and more than 2 million worldwide.
While scientists don’t fully understand what causes MS, some studies have linked low levels of vitamin D with a higher risk of developing the disease.
Hayes has been studying this “vitamin D hypothesis” for the past 25 years. She and her colleagues have discovered some of the molecular mechanisms involved in vitamin D’s protective action, and also found how vitamin D interacts with estrogen – which may influence the risk and progression of MS in women.
In the current study, which was funded by the National Multiple Sclerosis Society, Hayes’ team compared vitamin D-based treatments to standard MS drugs. In each case, the vitamin D-based treatments won out. Mice that received them showed fewer physical symptoms and cellular signs of disease.
Hayes compared the effectiveness of a single dose of calcitriol to that of a comparable dose of a glucocorticoid, a drug now administered to MS patients who had a bad neurological episode. Calcitriol came out ahead, inducing a nine-day remission in 92% of the mice. That compared to an average six-day remission in 58% of the mice that received glucocorticoid.
“So, at least in the animal model, calcitriol is more effective than what’s being used in the clinic right now,” says Hayes.
The researchers also tried a weekly dose of calcitriol – and found that it reversed the disease and sustained remission indefinitely.
The problem with calcitriol is that it can have some strong side effects. Hayes calls it a “biological sledgehammer” that can raise blood calcium levels in people.
So she tried a third regimen: a single dose of calcitriol, followed by vitamin D supplements in the diet. This one-two punch “was a runaway success,” according to Hayes, who says 100% of the mice responded.
While excited about the discovery, Hayes is quick to point out that it’s based on a mouse model of the disease. The next step is clinical trials in humans.
“It’s not certain we’ll be able to translate (this discovery to humans),” says Hayes. “But I think the chances are good because we have such a broad foundation of data showing protective effects of vitamin D in humans.”
“It’s my hope that one day doctors will be able to say, ‘We’re going to give you an oral calcitriol dose and ramp up the vitamin D in your diet, and then we’re going to follow you closely over the next few months. You’re just going to have this one neurological episode and that will be the end of it.’”
About 200 new cases of MS are diagnosed in the U.S. each week. Early symptoms include weakness, loss of dexterity and balance, vision disturbances, and difficulty thinking and remembering. As it progresses, people can lose the ability to walk, sit, see, eat, and speak clearly.
There is no cure for MS. Many FDA-approved treatments only work for some MS patients and the benefits are often modest.
According to one estimate, the average annual cost of an MS specialty drug is over $28,000. The cost is expected to nearly double in the next four years, with an annual price tag exceeding $50,000 per patient.