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Editorial: 鈥�Whose stem cells are they anyway?鈥�

THIS article began life last September, when an accusatory email landed in my inbox. It had come from SammyJo Wilkinson, a former internet entrepreneur in her late 40s, who lives in Seattle with her husband. Two decades after being diagnosed with multiple sclerosis, Wilkinson (pictured), is fighting a medical establishment that she reckons is thwarting her only chance of an effective therapy.

鈥淲e have a right to obtain these treatments and pieces like yours, that lack balance, will reduce our access,鈥� she wrote. 鈥淵our pieces are all written from the perspective of scientists with financial conflicts of interest.鈥�

The email left me a little piqued, I must admit, but also intrigued. I鈥檓 used to the idea that scientists aren鈥檛 all angels, having reported on research misconduct in the past, from image doctoring to wholesale data fabrication. Still, I didn鈥檛 recognise this picture of a conspiracy suppressing people鈥檚 only chance of a cure.

OK, I said to Wilkinson, let鈥檚 talk.

The therapies in question involve stem cells, routinely touted as the solution to many of the diseases that blight our lives. Just when this new era will arrive, however, is unclear, as the field is still in its infancy.

Despite the uncertainty, Wilkinson and others with similarly debilitating illnesses want to forge ahead with treatments using stem cells taken from their own bodies. Their problem is that the US Food and Drug Administration says that, under certain circumstances, such remedies are classed as drugs 鈥� which means they must first undergo a lengthy testing and approval process.

The row came to a head last September, when the FDA shut down a firm in Texas that was bringing hundreds of patients like Wilkinson the treatment they desired. Given the growing numbers of clinics around the world charging many thousands of dollars for unproven stem cell 鈥渃ures鈥�, it is easy to view the FDA鈥檚 move as part of an essential clampdown. But after lengthy conversations with Wilkinson and other activists, I鈥檝e come to see that the picture is more complex than it first appears.

Wilkinson put me in contact with a small but highly vocal group of activists who organise online through websites like . Their medical conditions differed but all had reached the limits of what orthodox treatments could offer them and saw stem cells as their only hope.

So what exactly are stem cells? Unlike most of the cells in our bodies, which have a finite lifespan, stem cells can keep dividing and replenishing themselves. They can also give rise to a variety of different specialised cell types 鈥� hence the optimism that one day they might be able to treat a whole range of conditions, from heart attacks to Parkinson鈥檚 disease, and diabetes to spinal cord injuries.

Embryonic stem cells, obtained from developing embryos a few days after fertilisation, can produce all the cells in the human body (see 鈥�Cell sources鈥�). Our bodies also contain small numbers of adult stem cells, which give rise to a narrower range of cell types, and normally help to maintain and repair our tissues. These include mesenchymal stem cells, or MSCs 鈥� the cells in which Wilkinson has placed her hopes.

Out of time

Found in bone marrow and certain other tissues, MSCs build bone, cartilage and fat. But it has recently emerged that these cells have another crucial property: they respond to injury and inflammation by releasing signalling molecules that can promote healing and damp down unhelpful immune reactions. 鈥淵ou need to think of MSCs not as stem cells but as drug factories,鈥� , who studies the cells at Case Western Reserve University in Cleveland, Ohio, told me.

Most stem cell treatments are years away from routine use. But those based on MSCs have advanced further. For instance, a treatment to promote healing in cardiac muscle after heart attacks was approved in South Korea in 2011. And dozens of , using MSCs in a wide variety of diseases, including Wilkinson鈥檚 condition, multiple sclerosis.

People like Wilkinson feel they do not have time to wait for these trials to complete. And they are wary of efforts by the International Society for Stem Cell Research to . They think the society鈥檚 researchers are acting to protect their own financial interests in rival stem cell therapies that are years away from fruition.

This view was expressed to me most forcibly by Albert Salazar, a marketing manager in South Manly, Florida, who has taken his son to a clinic in Mexico for treatment based on umbilical cord blood, another source of stem cells. His son has cerebral palsy. Salazar accuses mainstream stem cell biologists of talking up the potential risks of MSCs. 鈥淭hey masquerade under their altruistic intentions of protecting the general public, when in fact their motives are to protect their own interests,鈥� he told me.

I couldn鈥檛 help thinking of another caring father I have interviewed who is focused on stem cells: , a researcher at Harvard University whose mission to develop treatments for juvenile diabetes is driven by the fact that his own children have this condition. Did Salazar really think that Melton would suppress a cure for diabetes?

Salazar would not answer, saying he hadn鈥檛 heard of this researcher. When I later recounted the exchange to Melton, he responded: 鈥淭he idea that scientists are conspiring to make money and keep life-saving treatments from patients strikes me as ridiculous.鈥� I couldn鈥檛 help agree with him.

My body, my choice

How did the activists I was speaking to come to so distrust the medical establishment? When I thought about their personal histories, I began to understand. If I鈥檇 tried drug after drug that didn鈥檛 work 鈥� as some of these people had 鈥� then was blocked from trying an apparently promising treatment, I might be forming my own conspiracy theories.

So I decided to put the wilder accusations to one side, and listen to their other arguments. Some of these were more persuasive 鈥� especially their refrain that the FDA has no right to regulate cells taken from a patient鈥檚 body as if they are drugs. 鈥淲e鈥檙e talking about our own stem cells; our own body parts,鈥� says Barbara Hanson, who lives in Denver, Colorado, and suffers from chronic obstructive pulmonary disease (COPD), a severe and incurable lung condition that is slowly sapping her ability to breathe. 鈥淥ur civil rights are being violated.鈥�

While pressure from patients for access to experimental treatments is not unique to the US, this argument has particular resonance in a country that is suspicious of government involvement in healthcare decisions.

And the principle of allowing treatments made from a person鈥檚 own cells to advance without FDA approval has precedent, in IVF. Such assisted-reproduction techniques, also involving a patient鈥檚 own cells, never had to prove their worth in large trials.

Adding to the sense of injustice is the fact that the FDA is not moving against all US clinics that treat people with MSCs. If a doctor takes a person鈥檚 cells and puts them straight back into another part of their body, the FDA accepts that it cannot intervene. But if those cells are manipulated beyond a minimal threshold, such as growing them in the lab for a couple of weeks, then they become a drug. It鈥檚 a distinction that can seem arbitrary.

This row came to a head thanks to events in Texas, where in 2011 a company called began providing a service based on MSCs taken from a person鈥檚 abdominal fat. The firm expanded the cells by culturing them in the lab, before supplying them to doctors, who would inject them back into their patients.

Celltex had a prominent champion in Republican Texas governor Rick Perry, who received injections of his own MSCs to treat a back injury. Perry was keen for his state to become a powerhouse for therapies based on adult, rather than embryonic stem cells (to which he has ethical objections). Celltex鈥檚 cause was advanced last year, when the Texas Medical Board set new rules. These said that experimental techniques classed as a 鈥減ractice of medicine鈥� rather than a drug could proceed, if backed by a local ethics committee.

For patients like Wilkinson, everything seemed to be falling into place; she received stem cells processed by Celltex last year. But in September the FDA that its cell therapies must cease until the company filed an application for drug approval.

By then, more than 200 patients had been treated with cells processed by Celltex, and others were lining up to be next. Not surprisingly, the firm鈥檚 clients were angry at having the rug pulled from under them. 鈥淭he FDA has way overstepped its bounds,鈥� I was told by Bill DeVore, a real estate agent in Matthews, North Carolina. DeVore has received stem cell treatments for MS at a clinic in Panama, and was keen to get future therapies through Celltex without having to travel abroad. 鈥淭reatments of this sort should be between patients and their doctors.鈥�

The idea that the FDA鈥檚 system of drug approval is ill-suited to stem cell therapies has support from an unlikely source: the former head of the FDA from 2005 to 2009. Andrew von Eschenbach, who now works with the Manhattan Institute for Policy Research, a conservative think-tank in New York City, argues that the agency鈥檚 approach to stem cell therapies . The world of medicine is changing, he says. 鈥淭hat forces us to not simply be wedded to the past.鈥�

The clinical trials needed for FDA approval are supposed to show that a treatment is safe and effective. Wilkinson argues that safety has already been demonstrated, and she has a point: a recent , involving more than 1000 patients, found no serious safety issues.

But do they work? The new view of MSCs as tiny drug factories that promote healing provides a theoretical basis for how they could treat conditions as diverse as MS and COPD. That could explain the effects reported by some of Celltex鈥檚 clients. Wilkinson, for instance, sent me a chart tracking 25 symptoms of her MS, 11 of which she says resolved after her initial treatments.

Such evidence is a long way from scientific proof of effectiveness, though. How much of the improvements reported by patients might be due to the placebo effect? This proved to be an especially touchy subject when speaking to Wilkinson and other activists, who are convinced they have experienced benefits that cannot be explained by the placebo effect.

Given how hard it is to assess the evidence, most researchers would argue that a rigorous approval process is vital. 鈥淢edicine can only be enacted through good scientific principles. If it鈥檚 not, it鈥檚 quackery,鈥� argues , who heads the California Institute for Regenerative Medicine in San Francisco, which has spent years pushing stem cell therapies towards FDA approval.

For Trounson, those principles involve randomised, controlled trials, where the treatment is compared with a placebo. While Celltex says that it provided cells only to doctors who were conducting research, those trials lacked a placebo arm. Controversially, patients were also charged large sums for the treatment and cell processing. Wilkinson, for instance, paid a total of $28,000 for her first three infusions.

Yet Wilkinson bristles at the suggestion that patients need to be protected from wasting their money. 鈥淚鈥檓 an adult 鈥� I鈥檓 going to do my homework,鈥� she told me, adding: 鈥淭here鈥檚 not much point saving for your future if you don鈥檛 have a future.鈥�

鈥淭here鈥檚 not much point in saving for your future if you don鈥檛 have a future鈥�

Could treatments be allowed to go ahead and still be evaluated in a scientifically rigorous way? Yes, says von Eschenbach. He suggests that stem cell therapies could be put onto the market after their safety has been established, and then have their effectiveness gauged in post-approval studies. This would need the FDA to pull treatments off the market quickly if they are shown not to work, von Eschenbach says. At present, the FDA usually gets treatments withdrawn only if there are major safety concerns.

The FDA declined to comment on von Eschenbach鈥檚 suggestions, and is sticking to its guns in the Celltex case. The company is now talking to the FDA about running the trials needed to win drug approval, but is also making its cells available via clinics in Mexico, where the authorities do not regard them as drugs.

In June, Wilkinson travelled to Canc煤n to get her second round of stem cell infusions. When I called to see how that had gone she was delighted with the results, telling me excitedly how she had managed to make her own way to the front of the plane that flew her home, rather than waiting for a wheelchair.

I was glad to hear her in such good spirits, but troubled by questions for which I have no clear answers. Do I think MSC infusions are a panacea? Not without good scientific evidence 鈥� which so far is lacking. So is the FDA doing the right thing by pushing Celltex through the process of drug approval? I鈥檓 unsure, and can see little sense in a 鈥渕inimal manipulation鈥� threshold that puts Celltex under the regulatory spotlight but allows other US stem cell clinics, which don鈥檛 expand cells in culture, to operate with impunity.

In an era when treatments may be conjured from our own cells, rather than delivered in a packet of pills, we may need a new set of rules. And my conversations with Wilkinson and her fellow activists have taught me this: those rules must not only be strong on evidence, but should also convince patients that the medical establishment is working in their interests, rather than against them.

This article appeared in print under the headline 鈥淪tem cell crusaders鈥�