Monday, December 29, 2008

Stems and Blossoms (part 2): Really Informed Consent

There is a strain within the clinical and bioethics community that takes a minimal view of informed consent: investigators are supposed to provide requisite information to volunteers; if research subjects fail to comprehend this information, pity for them. This view brings to mind a memorable exchange between Inspector Clouseau and a hotel clerk (Clouseau: "does your dog bite?" Clerk: "No."  Clouseau then extends a hand; the dog lunges at him.  "I thought you said your dog doesn't bite." Clerk: "Zat is not my dog.")

The ISSCR guidelines take a bold stand on informed consent. "Investigators involved in clinical research must carefully assess whether participants understand the essential aspects of the study."  The guidelines go on to state "ideally, the subject's comprehension of information should be assessed through a written test or an oral quiz during the time of obtaining consent." Once again, ISSCR shows vision here in going well beyond the legalistic conception of informed consent described above.

The ISSCR guidelines also urge researchers to:
• explain possible irreversibility of some toxicities
• describe the sources of stem cells
• inform patients that researchers "do not know whether they will work as hoped"

These laudable recommendations aside, I might have hoped for more guarded language about the therapeutic value of early phase studies. For one, the guidelines use mostly "therapeutic" language, for example, using the aspirational term "cell therapy" instead of the neutral term "cell transfer." Second, the third item above logically means that the probability of benefit is less than 100%; experience tells us, however, that when interventions are highly novel, major therapeutic benefits for early phase trials are very improbable. (photo credit: Helen K, Stems, 2008)

Sunday, December 28, 2008

Stems and Blossoms (part 1): Justice

Shortly before I left for holiday, the International Society for Stem Cell Research (ISSCR) issued a policy paper, "Guidelines for the Clinical Translation of Stem Cells," outlining ethical and scientific considerations for researchers designing translational trials involving stem cells (whether stem cell derived, adult, or embryonic).

In my opinion, the document wins the award for most forward thinking and comprehensive statement on the ethics of a translational enterprise. It shows that the stem cell research leadership has closely studied mistakes made by translational researchers in other highly innovative fields.  But the guidelines do more than look backwards; they proactively contemplate fairness and justice considerations as well.  Here are a few justice-related excerpts:

On responsiveness: "The ISSCR strongly discourages conduct of trials in a foreign country solely to benefit patients in the home country of the sponsoring agency. The test therapy, if approved, should realistically be expected to become available to the population participating in the clinical trial through existing health systems or those developed on a permanent basis in connection with the trial."

On reasonable availability: "As far as possible, groups or individuals who participate in clinical stem cell research should be in a position to benefit from the results of this research."

On diversity: "Stem cell collections with genetically diverse sources of cell lines should be established"

On access and licensing: "Commercial companies, subject to their financial capability, should offer affordable therapeutic interventions to persons living in resource-poor countries who would otherwise be wholly excluded from benefiting from that stem cell-based therapy. Academic and other institutions that are licensing stem cell therapeutics and diagnostic inventions should incorporate this requirement in their intellectual property license"

On review: "Regulatory and oversight agencies (local, national, and international) must explicitly include the consideration of social justice principles into their evaluations."

On trial participation: "... the sponsor and principal investigator have an ethical responsibility to make good faith, reasonable efforts whenever possible to secure sufficient funding so that no person who meets eligibility criteria is prevented from being considered for enrollment because of his or her inability to cover the costs of the experimental treatment."

In upcoming posts, I will comment on other aspects of the ISSCR guidelines. (photo credit: Helen K, Stems, 2008)

Saturday, December 13, 2008

GenetEx Cathedra

On December 12, the Catholic Church issued what the New York Times called "the most sweeping document on bioethical issues," its Dignitas Personae.  The document– the summary of which is available on the web– is dominated by discussion of in vitro fertilization, embyro research, and stem cells. But there is a section on gene transfer– and following on my previous post, the degree to which gene transfer has receded from the public discussion is striking (for example, gene transfer gets nary a mention in the New York Times coverage on Friday).

Here is what the document has to say about gene transfer.  It defines "gene therapy" in a rather un-(small-'c')atholic way, as "techniques of genetic engineering applied to human beings for therapeutic purpses, that is to say, with the aim of curing gentically based diseases."  This excludes lots of what goes on in gene transfer, like cancer and cardiovascular disease gene transfer and gene marking.  It also excludes much of what is morally contested about gene transfer– namely, enhancement applications.  About "somatic gene therapy," the statement says that "in order to proceed to a therapeutic intervention, it is necessary to establish beforehand that the person being treated will not be exposed to risks to his health or physical integrity which are excessive or disproportionate to the gravity of the pathology for which a cure is sought. The informed consent of the patient or his legitimate representative is also required." Nothing startling about this statement. But a careful reading raises interesting questions. What, for example, is meant by "establish beforehand?" What type and degree of evidence is required? Are gene transfer applications not aimed at "therapeutic intervention," like gene marking or vaccines, exempt? Another question: why the word "cure" given that few if any gene transfer strategies actually cure. Why not the more inclusive "treat?"

The statement on germ line cell therapy is somewhat intriguing. The document stops far short of categorically condemning such practices, and instead advises against them given that "the risks... are considerable and as yet not fully controllable." In principle, then, the Catholic Church does not oppose germline gene transfer applied surgically to adults, fetuses, gametes, and embryos provided risks are manageable. But it is hard to imagine how these risks could be reduced for embryos without research that destroys embryos. It is also hard to imagine how the safety of gamete gene transfer could be established without the creation of "injured" embryos. If my analysis is correct, embryonic and gamete germline gene transfer are obliquely banned, leaving permissible application of germline gene transfer to fetuses with genetic illness provided benefits outweigh risks.

The document goes on to warn against "genetic engineering... with the presumed aim of improving and strengthening the gene pool." Such techniques "promote a 'eugenic mentality';" many disabilities activists (and medicalsocial constructivists) will be heartened by the admonition that these techniques "introduce an 'indirect social stigma with regard to people who lack certain qualities, while privileging qualities that happen to be appreciated by a certain culture or society...." Still, one wonders what, exactly, this condemns other than heavy handed state, or large collective efforts, to improve the gene pool (that is, genetic engineering with the aim of creating individuals who can fly, see in the dark, or think more clearly is not explicitly banned).

Somewhat surprisingly, the document contains no language on somatic gene transfer applied towards the ends of enhancement, though the spirit of the prohibition on cosmetic germline alteration would seem to rule out the use of such techniques. (photo credit: Vatican stairs, tintalle* 2007)

Wednesday, December 10, 2008

Soft Cells and C-Sections

The American Society of Gene Therapy is renaming itself: "American Society of Gene and Cell Therapy" (membership has yet to finalize the name change."  The European Society of Gene Therapy has already done so: "European Society of Gene and Cell Therapy."

Why is gene transfer going cellular? The publicly stated reasons are two fold. First is a recognition that gene transfer has always involved "cell transfer." For instance, ADA-SCID and X-SCID protocols-- for that matter, all ex vivo protocols– involve modifying cells outside the body, and returning them to the volunteer.

A second reason is to have a more "inclusive" society, and an "expanded membership base." I suspect this partly reflects a concern that cell-types might affiliate with groups like ISCT (International Society of Cell Therapy), which has a "gene therapy" committee, or perhaps also ISSCR (International Society of Stem Cell Research).

Of course, this raises the question of what ASGCT means by "CT." Does the society intend "American Society of Gene AND Cell Therapy," or is it "OR Cell Therapy (which would include protocols that do not involve genetic modification). I can't help but wonder what the realignment will mean for gene transfer. Since its founding, "gene transfer" has represented a kind of "invisible college" - an international network of collaborations and co-citations with a common set of concerns. Does renaming represent the demise of the gene transfer invisible college, as "genes" are absorbed under the more powerful social category of "cells?"  Or does it represent a promising extension of the network? Is this simply a reflection that in the first decade of the 21st century, "cells" are, in terms of scientific capital, what "genes" were to the 1990s? (photo credit: I like 2008)

Monday, December 8, 2008

Northern Lights? Canada and the New Tricouncil Draft

Since it's issuance in 1998, Canada's Tricouncil Policy Statement (Canada's policy on the ethics of human research) has had an influence on the practice of research ethics that has outsized Canada's population.  The three research councils– CIHR, NSERC, and SSHRC– are presently revising the Tricouncil, and a few days ago, a revised draft was presented on the CIHR web site.  

There is much to commend the newest version.  There are also a number of disappointments. I won't dwell on these here, however. Instead, I will focus on Tricouncil's revised language on phase 1 and gene transfer research.

The revised Tricouncil contains a definition of phase 1 that, in my view, is somewhat outmoded and not much of an improvement on the old version. Both emphasize the role of phase 1 in toxicity and dose determination, but do not encompass the many other purposes to which phase 1 trials are put (e.g. for deciding whether to pursue phase 2, for gathering evidence of biological effects, etc.).  On the other hand, the new Tricouncil requires prospective registration of all trials– including phase 1. And it contains a lengthy discussion of "therapeutic misconception," which it defines as "the tendency of trial participants to believe that the primary intention of research tests and interventions is to provide a therapeutic benefit to the patient-participant."  The document urges research ethics boards and researchers to "emphasize  which specific elements  of a clinical study are required for research purposes, as well as the differences between research and the standard clinical care they might otherwise receive."  Bravo.

The new Tricouncil also, for the most part, replaces the old language of "gene therapy" with the more neutral "gene transfer."  In a section on "Gene Transfer," the new draft warns about therapeutic misconception. It shrinks from any ethical statement on germline modification by deferrinng to Canada's Assisted Human Reproduction Act.  The remainder of the text notes the irreversibility of genetic alterations (not quite accurate), the potentially latent nature of gene transfer risks (a point I agree with), and states that research and ethical debate is evolving rapidly (a point I mostly agree with). Somewhat disappointingly, there is no mention of the need for centralized, transparent, or specialized review of such protocols.

On balance, these two sets of modifications are pretty good, though rather than anticipate the issues that are likely to arise in the next 5-10 years while this draft is in force, I worry a little that instead the draft represents a policy that I and others wish we might have had in the previous 5-10 years. Onwards and upwards! (photo credit: Studiolit 2006)

Thursday, December 4, 2008


Heaven help those perseverant souls who pursue translational research on neurodegnerative disorders.  New interventions in this area have just about the highest failure rate of any area of medical research. And last week, yet another promising strategy was shown ineffective in a phase II study.

The trial in question was testing Ceregene's gene transfer strategy against Parkinson's Disease (PD).  Ceregene was second out of the gate testing gene transfer against PD (the first was Neurologix).  In April 2008, I wrote about their phase 1 study results, which on the one hand seemed to suggest safety, while on the other hand did not show signs of a dose-effect nor a change in dopamine metabolism by imaging.  For me, the most troubling aspect of this protocol was its aggressiveness: researchers delivered vector along eight needle tracks to deep brain structures. Based on surgical complication rates in the published literature, the risk of causing permanent neurological deficits from cerebral hemorrhage was on the order of 7% in this study- and that's not including the additional risk associated with the vector itself.

On November 26, Ceregene announced results of its sham controlled phase II study of CERE-120.  First the good news: the press release described CERE-120 as "safe and well tolerated."  The bad news is that the investigators saw no difference in outcomes between the sham and active arms. The press release does not say whether any adverse events were reported; nor does it say anything about surgical complications. In the next few weeks, expect to see data on why, precisely, the strategy might have failed. (photo credit: bebob717 2006).