March 17, 2008 -- It sounds like a remedy straight out of a witch's brew: a cocktail of worm eggs, destined to hatch inside the bodies of those who swallow them.
But make no mistake, there's science behind this remedy. And doctors who are embarking on a small initial trial of the worm egg cocktail in patients with the degenerative condition multiple sclerosis have high hopes that it will one day offer another fight against the debilitating disease.
There are already some hints that this potential remedy, which involves drinking the eggs of worms known as helminths, actually works. A recent study out of Argentina suggested that people already infected with this kind of worm experienced fewer symptoms of MS than those who were not infected.
These findings have led to approval by the U.S. Food and Drug administration of a small trial of the therapy next month on five patients. The trial, led by University of Wisconsin Hospital neurologist Dr. John Fleming, will determine if a helminth egg cocktail will be tolerated by these patients, and perhaps relieve some of their symptoms.
The very fact that the trial is going forward has officials at Ovamed, the German company that produces the worm eggs used in the research, hopeful that the therapy will prove to be a useful treatment with few of the side effects associated with some other MS treatments.
"Because it is a very natural approach, it takes a few weeks until it can unfold its full mode of action to show considerable improvements," says Detlev Goj, CEO of Ovamed. "However, this is something we are happy to accept in exchange for lacking such severe side effects most conventional medications have."
Such a therapy has already proved useful in treating some sufferers of inflammatory bowel disease. And because the approach uses the eggs of worms that normally infect pigs instead of those that infect humans, scientists hope that the disease associated with natural infection with these parasites can be avoided.
But MS experts say that while the new technique is novel, it remains to be seen whether the unorthodox cocktail will yield the desired results.
"It's a great example of thinking outside the box and does seem to have some scientific rationale," says Dr. Hillel Panitch, professor of neurology at the University of Vermont College of Medicine and director of the MS Center for Fletcher Allen Health Care in Burlington, Vt.
But, he adds, "I think it's far too early to say anything about helping treat MS. The first step is to see if the five test subjects tolerate the treatment, if they become infected, and if they have any changes in their immune response."
Dr. John Corboy, professor of neurology at the University of Colorado Health Sciences Center and a specialist in the study of multiple sclerosis, agrees.
"Overall, there is little if any published data on using worms as a therapy," he says. "This will be a very small study, a 'proof of principle' study, and hopefully they will gather not just clinical data but also immunological data to understand the nature, if any, of the response."
A Battlefield in the Body
At the center of the potential success of this therapy is the action of the crucial T-cells in the immune system.
In a very basic sense, the T-cells can be thought of as the tiny platoon commanders in the body -- they are responsible for coordinating attacks on any dangerous invaders.
And, as with military field commanders, there are different strategies that these cells can use to eradicate an enemy. In one of these responses, the Th1 pattern, the T-cells initiate a nonspecific inflammation response from the body's immune system -- the biological equivalent of calling in a napalm strike.
The other option, known as the Th2 pattern, is a bit like radioing in a team of snipers -- a silent and precise strike against specific invaders. This immune reaction results in less inflammation than the Th1 response.
Both approaches are highly developed and effective. But in patients with MS, excess inflammation is already a problem. In these patients, inappropriate inflammation degrades the insulation of the nerves, known as myelin. Think of it as the "collateral damage" of the immune response, and it leads to the slowing of impulses along these nerves. This brings about the typical problems seen in MS, which include problems with vision, speech, walking, writing and memory.
That's where the worm egg cocktail comes in. When the worms hatch inside the intestine, they prompt the T-cells to call in the snipers instead of the napalm strike to kill them off. This, in turn, nudges the entire immune system into a less inflammatory mode -- in theory, at least.
"Pushing the immune system from a Th1 to a Th2 pattern is something that several of the current FDA-approved therapies for MS already do, and helminths seem particularly effective at doing this naturally," says Dr. John Richert, executive vice president of research and clinical programs for the National Multiple Sclerosis Society.
The 'Ick' Factor
But whether the treatment works or not, the simple idea of throwing back a shot of worm eggs might be revolting to some patients.
"I don't think it would catch on," Panitch says. "Besides, it could carry risks that make it unacceptable -- for example, the patient could infect the rest of his or her family."
Panitch adds that an alternative to drinking the eggs might be isolating the chemical produced by the worms themselves that triggers the desired immune response -- and trying this out on animals first.
But if the treatment turns out to be safe, Richert says, it could show a good level of acceptance among patients who are willing to consume the cocktail.
"A key, of course, will be to make the treatment suspension palatable from the taste standpoint," Richert says. "An oral therapy with a track record of success will likely be acceptable to people with MS, particularly if it is clear that the treatment is safe."
Corboy agrees. "If it is just taste, and if it is infrequent, it's likely not a big deal."