Expectation is a Vascular Condition: Thoughts on Media Coverage of "Liberation Procedures" for Multiple Sclerosis

Disclaimer to all readers: I am not expert in multiple sclerosis. I am not intimately familiar with recent research findings on a novel surgical treatment ("liberation procedure") for multiple sclerosis that have received wide coverage in the Canadian media.

Now here are my "claimers:" recent media accounts of this novel approach border on the irresponsible, and point to serious problems with the way many media outlets cover translational clinical research. My second "claimer" is that such media coverage has important consequences for patients and the research community.

Finally, a point of clarification: my comments below concern the quality and consequences of media coverage, not the merits of the medical procedure discussed.

Here is the background: on November 20, the Globe and Mail ran a feature by veteran reporters André Picard and Avis Favaro titled "Researcher's labor of love leads to MS breakthrough." The story described a novel theory of an Italian researcher, Paolo Zamboni, that MS "is not, as widely believed, an autoimmune condition, but a vascular disease. More radically still, [an] experimental surgery offers hope that MS... can be cured and even largely prevented." Said Dr. Zamboni, "I am confident that this could be a revolution for the research and diagnosis of multiple sclerosis." The news story then describes an Italian study that performed the surgical procedure in 65 patients; the patients saw their disease virtually eradicated.

Like practically every other news article of this species, the reporters do two things. First, they truck out a few patients to proclaim the miracle cure (said one: "I don't remember what it's like to have MS"). Second, to establish credibility, the reporters throw in the perfunctory killjoy comments of a few scientists: "skeptics warn the evidence is too scant and speculative."

As observed on the excellent NPR program On the Media, media coverage of medical research and breakthroughs "overflow with optimism and excitement, offering hope for millions." According to long-time media analyst Gary Schwitzer, "What they don't overflow with is accuracy, context and journalistic responsibility." (Schwitzer, by the way, runs an excellent blog on health news coverage).

Here are some concerns I had about the Globe and Mail story:

• the story reports on clinical research findings. The story did not say, however, that the results have not been published and subjected to peer review.

• the story did not say whether the studies were well-designed: was there a control or placebo arm, for example? the story did not mention that placebo responses can be especially high in the setting of surgical interventions. Nor did it mention that placebo responses are often high in the context of remitting diseases like MS.

• the story wrapped logical fallacies within emotive proclamations. For example, what, precisely, could it possibly mean to say "I am confident this could be a revolution..."?

• the story was not linked in any way to any particular event. Usually reports like this follow from major scientific publications, or presentations at medical conferences. This story, however, is "free floating"- which makes it much more difficult to contextualize (why is it being reported now? how well have the findings been vetted? how did the researchers capture the attention of journalists?).

• the story contains statements that are deeply suspicious. One example is that Zamboni claims MS is not an autoimmune condition. Here is the very first line in the abstract of Professor Zamboni's most recent publication: "Multiple sclerosis is primarily an autoimmune disorder of unknown origin."

• the story did not address the correlation and causation problem. The story (and Zamboni) claim that vascular malformations cause MS symptoms, because the researcher discovered that many MS patients have "malformed or blocked" veins draining the brain. But an alternative explanation would be that malformations or blockages are themselves caused by MS- that they are symptomatic rather than causal. Any news coverage of correlation should always address the issue of cause.

And the consequences? Do a google search yourself on the procedure (CCVSI) to find out how much chatter there is among expectant patients, who (judging from discussions) are wondering whether they can travel to Italy to receive the "treatment." And today, the Globe and Mail reports that the MS Society of Canada- portrayed as sourpuss nabobs of negativism in the previous article- will now fund CCVSI "with significant research dollars" in response to "the overwhelming public response to the media stories."

Surely, more research, more trials, more basic science is needed. If indeed this approach is a promising as reported, it should be subject to rigorous clinical testing. But can anyone seriously argue that media coverage of this low quality should set the research agenda and decide how scarce research resources are allocated? (photo credit: xbloodsin, sepulcrum, 2008)

More on Lenti's, Gene Transfer and Adrenoleukodystrophy

(...continued from the previous post). There are several features that make the recent Adrenoleukodystrophy (ALD) gene transfer study noteworthy.

1- A New Viral Vector Debuts: this is the first successful application of HIV-derived viruses in gene transfer (lentiviruses). These vectors have various advantages over retroviruses used in other protocols. One is that, in theory, at least, they are supposed to be safer. Previous trials of the same team (different disease) involving retroviruses triggered leukemia-like disorders in several volunteers. In this study, the authors do not detect any evidence that cells are poised to cause a malignancy. However, in a post this summer, I noted that another trial involving thalessemia and lentiviruses did, indeed, detect clonal enrichment. And the ALD study enrolled only two patients- if there were going to be safety problems detected, they'd need to be massive to be detected in so small a sample of patients. Thus, despite the encouraging findings in the ALD study, the safety of lentiviral gene transfer remains to be firmly established.

2- Prior Animal and Clinical Experience are Successfully Integrated: here is one instance where favorable clinical outcomes were achieved on the basis of limited preclinical evidence. Specifically, the authors previously tested their approach in mice, but because rodents do not develop the same pathology as human beings, they were uncertain whether the gene correction would be sufficient to correct the disorder in human patients. These animal studies were bootstrapped with extensive experience with bone marrow transplantation in children with ALD. Rarely is this transition from rodents into clinical applications so successful. All the more surprising- this is occurring within the realm of central nervous system disorders, which have a particularly high rate of failed drug development.

3- Patients in the Service of Science: This study will no doubt be perceived as a story of "science in the service of patients:" a team of clinicians applying cutting edge discoveries to do the best they can for their patients. But it is as much- perhaps more- a story of patients in the service of science. The study is notable for how well it used the occasion of ALD to make more fundamental discoveries. For example, in a "Perspective" piece that accompanies the published trial, Luigi Naldini describes this as what "may be a first glimpse of live [generation of new blood and immune cells at the level of DNA]." Naldini also notes how the study developed and applied new techniques for ruling out clonal dominance that "will likely become a gold standard." Also intriguing is the hint that this approach may be applicable for other disorders involving the central nervous system, and the finding that only a small amount of gene correction is needed to arrest the pathology. (photo credit: photobunny 2007)

Gene Transfer and Adrenoleukodystrophy: There Will Always Be Paris

Last week's Science magazine reported what seems likely to count as one of gene transfer's greatest clinical successes to date: stabilization of adrenoleukodystrophy in two boys receiving genetically modified blood stem cells. Preliminary results of this study had been presented at this summer's American Society of Gene and Cell Therapy meeting.

Adrenoleukodystrophy (ALD) is a rare hereditary brain disorder in which a deficiency in a gene, ABCD1, causes degeneration of tissues (myelin) that insulate cells in the central nervous system. The disease is familiar to many because of its most famous patient, Lorenzo Odone, whose story was featured in the movie Lorenzo's Oil. Untreated, ALD is invariably fatal.

Because myelin cells originate from blood stem cells, researchers had previously used bone marrow transplantation to successfully halt progression of demyelination in ALD patients. However, bone marrow transplantation has two severe limitations: many patients lack matched bone marrow donors; second, even when a matched donor is available, the procedure is burdensome and risky.

In this most recent study, researchers at Hôpital Necker in Paris transplanted genetically modified bone marrow cells into two Spanish boys who lacked matched bone marrow donors. The boys were also given myeloablative conditioning- a type of chemotherapy that increases the likelihood that genetically modified cells will repopulate the bone marrow. The Science report showed:

1- genetically modified cells did, indeed, survive and were maintained at stable levels for two years.

2- the modified cells expressed the therapeutic gene, ABCD1, again for two years.

3- brain demyelination was halted after 14 months- the timing is similar to what would occur for patients receiving bone marrow transplantation.

4- the two boys did not appear to decline on various measures of neurological or verbal tests, as would almost certainly have occurred with the natural course of ALD.

5- the authors did not detect "clonal dominance" in their modified cells– that is, evidence that genetically modified cells were poised to cause a malignancy.

In an accompanying editorial, Luigi Naldini calls this study a "Comeback for Gene Therapy," describing it as a "long-sought rewarding achievement in the field of gene therapy." In my next post, I will discuss some implications, interpretations, and other interesting dimensions of this very encouraging study (photo credit: tgif28, chalk graffiti at Hopital Necker, 2009)

California Dreamin: CIRM Announces New Stem Cell Awards

California's Institute for Regenerative Medicine just announced a series of large funding awards to fund translational research initiatives involving (mostly) stem cells. The projects funded are telling with respect to what was funded, and what they will attempt to achieve.

First, notwithstanding a press release containing the words "bringing stem cell therapies to the clinic," several projects are really dressed up gene transfer studies. Thus, one team will use gene transfer in hematopoietic stem cells for sickle cell anemia; another two will use gene transfer to stem cells for treating brain malignancies; another RNAi for HIV. All this is only further evidence that the field of stem cells is devouring gene transfer. Other projects are aimed more at getting "stem cells out of the clinic" by using small molecules or monoclonal antibodies to destroy stem cells causing malignancies.

Second is the sweeping ambition. As it stands today, only one clinical trial involving embryonic stem cell-derived tissues has been initiated. The projects funded under these awards are "explicitly expected to result in a filing with the FDA to begin a clinical trial." Given that these projects are funded for four years, CIRM seems to be banking on the prospect of at least a few of these initiating phase 1 trials within five years. Four of these proposals involve goals of implanting embryo-derived tissues, and two of these involve non-lethal conditions–macular degeneration and type I diabetes (technically, other awarded projects involve nonlethal, though extremely morbid conditions). Another involves implantation of embryo-derived tissues for Amyotrophic Lateral Sclerosis. It will be interesting to see how many of these meet their translational objectives, and how investigators will navigate the ethical, regulatory, and social complexity of initiating clinical testing. (photo credit: Michael Ransburg, 2008)

The Need for Speed: GAO Reports on Accelerated Approval

Several blog posts ago, I wrote about the policy of accelerated approval (briefly, a mechanism whereby new drugs can be approved for sale by the FDA before definitive evidence of efficacy and safety are available). In that post, I reported on a recent paper where the authors claimed that, all things considered, accelerated approval enabled patients to get quicker access to life saving drugs without major adverse impacts on patient safety.

Last week, the Government Accounting Office issued a report on the subject that took a less favorable view of the program. Rules require that companies receiving accelerated approval for new drugs complete post-marketing studies confirming their efficacy. The GAO investigated the frequency with which companies fail to submit post-marketing trial data. They found that over a third of FDA-required post-marketing studies aimed at confirming efficacy had not yet been completed. Many of these studies might be incomplete because accelerated approval was only recently granted, and it can take as long as five years to complete requested studies. Disturbingly, however, the report found that a quarter of these studies had been incomplete for over five years; other studies have been completed but not yet reviewed by the agency. The figures are worse for other types of post-marketing studies requested by the agency.

The "poster boy" drug singled out in the GAO report is the hypertension drug Proamatine, which earned Shire Pharmaceuticals $257M since it was approved under accelerated approval 13 years ago. Apparently, the drug has not been subject to adequate confirmatory testing in all this time, though FDA has issued warning letters to the company over its promotion practices.

The report saves its criticism for the FDA, which it says has not reviewed sponsors' submissions in a timely manner, does not adequately monitor progress of post-marketing studies, and has neither specified conditions under which it would exercise its authority to withdraw drugs from market, nor has it ever exercised its authority to do so. But isn't some criticism also warranted for companies exploiting FDA's deficiencies? (photo credit: lindsay kay photography 2009)

Remembrance of Things Past: Fetal Tissue Transplantation and Parkinson's Disease

In a recent article in Science magazine, Constance Holden reports that European researchers are contemplating a revival of fetal tissue transplantation for the treatment of Parkinson’s disease. As the article recounts, fetal transplants were subjected to sham controlled studies in the late 1990s; none performed better than sham, and several caused disabling dyskinesias. So should fetal tissue transplantation be revived, and if so, how?

The challenges seem all the more formidable today. We now understand that Parkinson’s disease is not restricted to the dopaminergic neurons in the basal ganglia, but instead involves diffuse pathology. And yet, studies will not involve implantation of tissues throughout the brain. As Holden’s article points out, previous fetal transplant studies revealed that brain pathology spreads to implanted tissues, suggesting that permanent responses may be difficult to achieve.

The ethical issues seem just as daunting. Deep brain stimulation has greatly improved the management of Parkinson’s for patients who are no longer responding to dopamine replacement. And yet, those pursuing fetal tissue transplantation will likely advocate pursuing trials in younger patients with less advanced disease. As pointed out by a European team of researchers, "A significant effort of bioethical research and conceptual clarification is required in anticipation of the first protocols involving human subjects." And in a recently published article in Movement Disorders, several coauthors and I outline various ethical challenges presented by such studies. These include a high degree of uncertainty about the safety of interventions, and a baseline risk associated with delivery that approaches levels of risk encountered in phase 1 cancer trials (for studies that involve eight inoculations to the brain, risk of intracerebral brain hemorrhage leading to permanent neurological deficits is on the order of 2%).

Advocates of the new wave of studies insist we know much more about the properties of fetal tissues than we did in the 1990s; they further note that such studies will provide a basis for later studies involving induced pluripotent stem cells and other tissues. Perhaps, but given the remaining uncertainties and promise of DBS, it’s hard to imagine how fetal graft experiments could credibly establish a claim of clinical equipoise with deep brain stimulation. For these reasons, a more prudent ethical course—if fetal transplant studies for Parkinson's are to be done at all—would be to pursue safety and feasibility studies in patients who are no longer responsive to standard care. Only once parameters are optimized and mechanisms well understood should clinicians consider studies in patients who are earlier in the disease process. (photo credit: Ethan Hein 2008)

Disclosure in Phase 1 Cancer Trials

Followers of this blog may recall my continuing concern with the way informed consent is obtained in phase 1 trials involving patient-volunteers (typically, these patients have exhausted standard care options and enter phase 1 trials as a final shot at managing their disease). Language used by investigators in these studies is often suggestive of therapeutic benefit, even though meta-analyses of phase 1 studies show that chances of major clinical benefit in phase 1 studies are exceedingly low. In previous posts, I described my own experience with an ethics review committee that actually defended giving patients vague and almost meaningless information about the therapeutic benefits of phase 1 trial participation. Meantime, evidence from surveys indicate that phase 1 cancer patient-volunteers tend to overestimate the probability of therapeutic benefit.

In the July-August 2009 edition of the ethics journal IRB, Shlomo Koyfman and co-authors at NIH offer up a "Consent Form Template for Phase I Oncology Trials." Their recommendations are comprehensive and excellent. Among the items they recommend are:

• use of more therapeutically neutral language, like "research agent" instead of "therapy"

• disclosure of dose escalation design; in particular, the authors recommend that patients be informed about risks and benefits relative to the cohort they are entering.

• a statement (where appropriate) that patient-volunteers will not have the option of adjusting their dose assignment in the study

• a statement that "the chances that this agent will... allow you to live longer [is] very low."

One can quibble with various particulars (I think, for example, discussion of subtherapeutic dosing should be more explicit). But on the whole, these recommendations provide an excellent standard– along with NIH Guidance on Informed Consent for Gene Transfer Research– against which typical phase 1 cancer study consent forms should be measured. (photo credit: banlon1964)