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

Sourgene

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).

Saturday, November 29, 2008

In Brugge / No Compassion (Part II)

Further to the therapeutic outlook on first-in-human studies at the Brugge meeting was Adrian Thrasher's thoughtful presentation on his own X-SCID study at Great Ormand Street Hospital. Thrasher's study was able to restore immune function in nearly all volunteers. Recently, however, his team reported a lymphoproliferative disorder like those seen in a very similar Paris study.

Thrasher stated clearly "The purpose [of X-SCID protocol] is therapeutic effect; it is not a safety study."  Fair enough: the study was in a pediatric population (standard research ethics requires clear therapeutic warrant for such risky studies), and Thrasher's protocol did not range doses the way typical first-in-human studies do. And I should add, there is some grounds for thinking of the study as having therapeutic warrant, not the least because it was supported several unsuccessful X-SCID human studies and a successful one in Paris). Still, putting the therapy before the learning- this made me somewhat uncomfortable.  Therapy might have been his (and his hospital's) intent, but to describe the study as ontologically "therapeutic" and not "research"?  Intent only gets us so far...

Thrasher revealed some unusual properties about the molecular events leading to this leukemia (see? told you it could be construed as a safety study).  And now, here's the compassion part. Thrasher was circumspect about this particular leukemia, because the patient who developed the leukemia had originally been ineligible for the protocol because he had a matched unrelated bone marrow donor. The regulatory agency made a "one-time" exception to waive the normal risk-benefit balance.

Of course, one should be very careful generalizing from this one case where "compassion" seems to have led authorities astray. And presumably, the boy's parents were thoroughly informed about the risks going in to the protocol. Still, the example is somehow instructive. (photo credit: missinguigga 2008).

Wednesday, November 26, 2008

No Compassion

"They say compassion is a virtue...." so sang David Byrne of the Talking Heads.  But what about "Compassionate Use?" 

This refers to the practice of giving terminally ill patients who are otherwise ineligible for early phase clinical trials access to investigational agents. At the Brugge ESGCT meeting, Finnish researcher Akseli Hemminki described providing 125 patients compassionate use access to a novel oncolytic gene transfer vector– Ad5/3-Cox2L-D24. Hemminki was not reassuring when asked by an audience member whether a concurrent clinical trial was actually testing the approach, and rumors swirled that he had charged patients for the agent.

Compassionate Use is highly controversial.  Patient advocates view it as a lifeline, and over the years, drug regulators like FDA and EMEA have eased restrictions on patient access to untested agents.  In late 2006, for example, the FDA proposed new rules that would make it easier to provide untested agents to groups of patients (rather than individuals); the rules would allow companies to recover manufacturing costs from patients seeking access. A related set of proposed new rules would allow companies to charge patients for entering early phase clinical trials. 

Compassionate Use raises troubling questions for ethics and policy. With respect to the former, is it really an act of compassion to offer terminal patients a completely untested composition of matter? If the answer is "yes," well, that makes any future clinical trial that will randomize some patients to standard of care (which, for terminal patients, is nothing) diabolical. That leads me to the policy concerns: if you can get access to a drug outside a study, why enter the trial at all? Compassionate use potentially complicates the collection of rigorous data about the safety and efficacy of new interventions, and thus has public health implications. As for the idea of actually charging patients for access– whether on or off a trial: that's plain wrong.

According to the American Cancer Society, no records are available on the number of agents provided through compassionate use, the volume of patients who receive drugs through compassionate use, or their outcomes. Regardless of where one stands, the practice would seem a policy black box.  (photo credit: fgm878, 2007).

Monday, November 24, 2008

In Brugge: The Cure

One of the most striking themes at the European Society of Gene and Cell Therapy was the extent to which continental European researchers conceptualize first-in-human gene transfer experiments as therapeutic interventions rather than research protocols.

Perhaps the most extreme and explicit expression of this was view was presented by Bonn internest Thomas Heinemann (he also studied philosophy and serves on several ethics committees in Germany). Heinemann advanced the notion of the "controlled individual therapeutic attempt," for which the primary objective is therapeutic gain; the scientific dimensions of such studies (e.g. collecting safety data) are necessarily secondary. As he put it, research is only justified "ex post facto."

I found this argument intriguing for several reasons. First, Heinemann justified this claim largely on grounds of autonomy and instrumentalization of desperately ill patients. In contrast, North American bioethicists typically use autonomy and instrumentalization to argue the opposite: that research is primarily intended to serve the ends of others, hence the paramount importance of obtaining consent from volunteers and their guardians, hence the need to be extremely cautious going into a desperately ill population, where autonomy might be compromised.

Second, I was impressed by the speaker's conviction that first-in-human trials have therapeutic warrant. After almost twenty years of painstaking and at times discouraging research, we seem to have learned two things:  first, that first-in-human trials rarely go as expected, and second, that such studies often yield important insights about new interventions. I might have expected a more cautious and seasoned view about the therapeutic merits of first-in-human attempts: does it really enhance the autonomy of volunteers to offer so little by means of therapy, but to foreseeably get so much in terms of social good? (photo credit: virtualais //www.77click.it, Brugge, 2008)

Tuesday, November 18, 2008

Just the FACS: Reprise on Insertional Mutagenesis

I've just returned from the annual European Society of Gene and Cell Therapy meeting in Belgium.  Lots of great material for upcoming posts. For now, I want to follow on the last posting on the leukemias in the X-SCID study.  A warning: those lacking a stomach for science geek-talk might want to skip this posting.

In the previous posting, I stated that a recent paper provided evidence that retroviral integration in the genome ("insertional mutagensis") had triggered leukemias in the X-SCID study rather than over-expression of the corrective gene ("transgene"), the gamma c-chain (hereafter, "gc").  This was on the basis of data in the graphic above, which used cell sorting to show that levels of gc on the surface of T-cells was within a normal range.  In Belgium, Adrian Thrasher presented similar data for the fifth leukemia.

When I first encountered this figure, it bothered me: why did the authors measure gc expression by cell surface markers (a technique called "FACS") rather than Western or Northern blotting, or quantitative PCR, or something along these lines?  It seemed a very indirect way of seeing whether gc expression levels are in fact normal. Here are two possibilities that this figure fails to rule out:  1- gc is expressed at very high levels, but not packaged and presented on the surface of T-cells, perhaps because of insufficiency of other receptor components; 2- some gc transgene is aberrantly spliced, such that surface levels are normal, but intracellular concentrations of the alternate splicing product are abnormal.

A few years back, one team of researchers presented data indicating that gc transgene overexpression contributes to T-cell transformation. Another team claimed it was unable to reproduce this. The jury seems to still be out on whether the gc product contributed to the X-SCID leukemias, and I'm not yet convinced that the latest round of data fully exonerates the gc chain. (Graphic: figure from Salima Hacein-Bey-Abina et al, J Clinical Investigation 2008; 108: 3132-42).

Thursday, November 6, 2008

Burst Bubbles

Among the greatest traumas for gene transfer was the development of leukemias in several children participating in trials using retroviral vectors against X-linked Severe Combined Immune Deficiency (X-SCID-- also known as "bubble boy syndrome").  About 20 or so children have had their immune systems fully restored by this gene transfer strategy.  Tragically, however, five children in two X-SCID studies (one in Paris, the other, London) developed T-cell leukemias that were causally linked to the gene transfer approach.

In the September 2008 issue of Journal of Clinical Investigation, Salima Hacein-Bey Abina and 28 other authors characterize the molecular nature of four of the adverse events, and report the outcome.  Before this article, it was known that one of the children died. This article now reports that the other three children have "sustained remission" after chemotherapy. 

The authors report that the vector inserted itself at the same genetic locus (LMO2) in 3 of the 4 cases.  In one case, vector inserted at a different genetic locus (CCND2); in another, vector inserted itself at LMO2 as well as a second locus, BMI1.  This suggests that LMO2 disruption is not the only path to causing cancer for this vector.  One other finding stood out.  Since the first leukemia was detected, many have speculated that the cancer was partly caused by the gene (rather than just the vector). However, the authors present evidence that the gene was expressed at normal levels in the children who developed leukemia. This lends support to the theory that the leukemias were not caused by the gene, but rather by some combination of the vector, the cell types used, and perhaps some characteristic of the underlying disease. (photo credit: concretecandy, boy in the bubbles, 2006)

Wednesday, November 5, 2008

Keeping Alive with Hope

Hope has been a consistent theme in Barack Obama's campaign, which thankfully came to a glorious end (many of us can now "hope" to actually get some work done after weeks of checking fivethirtyeight.com every ten minutes). His book was titled The Audacity of Hope. In the close of his victory speech, he stated "Let us keep that promise, that American promise, and in the words of scripture hold firmly, without wavering, to the hope that we confess." Newspaper headlines proclaim "Elections Unleash Flood of Hope Worldwide (NYTimes) and "Time to Hope Again" (Washington Post).

Hope is also a central theme in translational research, driving research advocates ("Hope for a Cure"), perseverance at the lab bench, and for better and for worse, the participation of gravely ill patients in trials that offer the slimmest prospect of serious medical benefit. Hope in many settings– particularly in the political– is an unalloyed good. 

But in the context of enrolling patients in early phase trials, hope becomes morally ambiguous.  Or at least, so Penn philosopher Adrienne M. Martin would seem to suggest in her critical analysis of hope ("Hope and Exploitation," Sept / Oct issue of Hastings Center Report).

Martin begins her essay with a set of consensus observations about hope: 1- it involves a desire for an outcome; 2- it involves imaginative engagement with a desired outcome– like praying or fantasy; 3- it often frames how people interpret and use information.  She then goes on to explore the various ways that hope can lead to exploitation in clinical research.

Much has been written about "hope" in bioethics, and much of it is drivel. I have a number of reservations about Martin's article. For my money, however, this is the most compelling analysis of the phenomenon that I know of. I highly recommend this article to anyone who takes seriously the moral dimensions of how translational research engages hope. (photo credit: San Diego Shooter, Tattered Hope, 2008)

Wednesday, October 29, 2008

Cash Crash

Think you're the only one stashing your financial statements in a filing cabinet without first opening them?  How do you think biotechnology companies feel?  Today's New York Times ran a story by Andrew Pollack ("Broader Financial Turmoil Threatens Biotech's Innovation and Cash") describing the impact of the economic downturn on the biotechnology sector. Among the observations:

- Of 344 companies that NASDAQ is considering de-listing because share prices have fallen to less than a dollar, 25% are biotechnology companies.

- 113 biotech companies now have less than a year's cash at current spending rates. This is up from 68 in the first quarter.

- One company with major problems is DeCode- the Icelandic genetic research company. This might have particular symbolic significance, given the company's profile.

- companies are being pressured by investors to cut their research and focus energy on lead products only.

The article goes on to explain that the main problem for biotech companies is NOT credit (apparently, even banks considered most biotech's too risky to lend to). Instead, the problem is an epidemic of risk aversion among investors, and hedge funds selling biotech stocks to recoup losses elsewhere in their portfolios. The article does note that companies like Amgen, which have widely used products, are thriving compared with the general market. As for the others, one analyst, Andrew Baum, describes the sector as a plane "for which the financial crisis just tipped the nose straight down." The implications for translational research are obvious. (photo credit: Hawk914, Koga's Zero- 1942, 2007)

Tuesday, October 28, 2008

The Future of Pharmaceutical Regulation

The October 2008 issue of Nature Reviews--Drug Discovery contains a very informative perspective piece on how drug regulators negotiate uncertainty, risk, and benefit when making approval decisions ("Balancing early market access to new drugs with the need for benefit/risk data: a mounting dilemma"). I have long argued that novel biologics like gene transfer will require creative approaches from regulators, because on the one hand many types of adverse events might be latent and unpredictable, while on the other hand, many novel biologics will target highly morbid or lethal conditions like primary immunodeficiencies.

The authors (Hans-Georg Eichler et al) are all employees of drug regulatory agencies in Europe. Not surprisingly, then, the article is balanced and presents drug agencies as making appropriate trade-offs between patient access and public safety. The article studiously avoids any criticism of pharmaceutical companies. And it makes some questionable claims. For example, in several passages it suggests that drug regulation is increasingly "risk averse" (it seems to me the opposite, but who knows?). Another is that the article contains ample evidence that premature approval has had important costs in terms of health and economics. Nowhere does it provide clear evidence or anecdotes that delay of approval, or restrictive evidentiary standards have had important public health or economic impacts (it might, but if you are going to suggest that the balance is appropriately struck, one needs a clear picture of the benefit side of the equation).

The article contains a number of observations and policy approaches that cry out for careful ethical analysis. Here are two:

1- Drug regulatory agencies accept greater uncertainty about safety and efficacy when new drugs address serious, unmet health needs. Thus, new cancer drugs can be approved on a weaker evidentiary base than new acid reflux drugs (in several instances, new drugs were approved on the basis of uncontrolled, surrogate endpoints (e.g. gefitinib). Why should evidentiary standards be relaxed in this way? And to what degree? If the disease is serious enough and standard care non-existent, then what is the basis for any drug regulation?

2- The article states that "rare drug reactions will continue to be identified only after wider use in the market," and that more sophisticated approaches to drug safety will increasingly "blur the line between pre-marketing and post-marketing activities." How will this affect ethics review and oversight? How will privacy protections be maintained in this gulf-stream of flowing health data? How will trial registries absorb and respond to post-marketing studies?

This article contains multitudes– I highly recommend it to anyone interested, as I am, in the problem of uncertainty, risk, and drug regulation (photo credit: Alincolnt, schedule 5, 2006)

Tuesday, October 21, 2008

Cancer, Low and Middle-Income Countries, and Translational Research

In the October 20, 2008 issue of Journal of Clinical Oncology, oncologist Zeba Aziz describes morning rounds in a cancer ward in Lahore, Pakistan. The first patient earns $20 a month and requires a combination therapy costing $10K. In the second case, a father can only pay 15% of the treatment needed by his daughter. The third case involves a single mother, who showed a significant tumor response on the first cycle of treatment but can not afford subsequent rounds.

According to Aziz, only 2% of Pakistan's population has health insurance; 95% earn $30-100 / month. Aziz's hospital serves 10K cancer patients annually, and has a medicines budget of around $80K each year. Treatments that wipe out the immune system are especially tricky, because medicines for infection might not be affordable.

Low and middle-income countries (LMICs) are undergoing an epidemiological transition in which chronic diseases replace infection as the main drivers of mortality. According to Franco Cavalli ("The World Cancer Declaration: A Roadmap for Change," Lancet Oncology, September 2008), cancer kills more people worldwide than AIDS, tuberculosis, and malaria combined. Cavalli describes a "World Cancer Declaration" issued by the Geneva based International Union Against Cancer that calls for improvements in the prevention, detection, reporting, and treatment of cancer in LMICs.

But a serious response to cancer in LMICs will require changes in translational research as well. Clearly, the vast majority of cancer treatment research is directed toward markets in high-income countries. These treatments have properties– costs, side-effect profiles, demand for ancillary services– that make their application in LMIC populations improbable. If, as argued by many commentators, we in HICs have a duty to persons in LMICs, translational researchers and funding agencies should give some thought and effort to the development and testing of treatments that, while perhaps not adding as many weeks of extra median survival, are deployable in settings like Aziz's clinic. (photo credit: CasaDeQueso 2008)

Thursday, October 16, 2008

From Bench to Ringside: The Presidential Debate

Last night, Obama and McCain confronted each other in the final Presidential debate. A flagging economy and two wars have left little room in the two campaigns for discussion of science, policy, and human research. Yet last night's debate touched on two themes: embryonic stem cell (hES) research, and biomedical research funding.

Obama accused McCain of opposing embryonic stem cell research. From what I can tell, McCain actually supported the use of embryonic tissue for research and opposed Bush's ban and vetoes. But the logic of McCain's attacks on Obama, of late, are that personal associations tell us something about who a person is and where they stand. And McCain pals around with embryo research opponents like his running mate.

Contrast the two candidates' statements on hES research from Sciencedebate 2008– a group that invited McCain and Obama to declare positions on various science policy issues. McCain stated "While I support federal funding for embryonic stem cell research, I believe clear lines should be drawn...."  The remainder of his response qualifies his support.  On his own website, McCain stops short of declaring support–or opposition– for hES research, and talks more about what he would oppose than what he would support.  Obama's support is more full-throated at Sciencedebate 2008: "As president, I will lift the current administration's ban on federal funding of research on embryonic stem cell lines... embryonic stem cells remain the 'gold standard,' and studies of all types of stem cells should continue in parallel for the foreseeable future."

Elsewhere at Sciencedebate 2008, Obama's campaign singled out gene transfer in a statement on genetics: "As a result [of safety issues involving 'gene therapy'], the NIH established the Recombinant DNA Advisory Committee.... Until we are equipped to ascertain the safety of such methods, I will continue to support the activities and recommendations of the Recombinant DNA Advisory Committee." [Note: Harold Varmus chairs a science advisory committee for the Obama campaign. Varmus reorganized RAC when he was the director of the NIH under the Clinton administration]

What about research-- specifically translational research?  Just as they do for Joe the plumber, both candidates support NIH research. According to a report in Science ("Scientists Strive for a Seat at the Table of Each Campaign," Jeffrey Mervis, 26 Sept), Obama pledged to double the NIH budget in five years. Elsewhere, his campaign said 10 years. Maybe the latter figure is inflation adjusted? Obama's statement on Science and Innovation singles out "rapid translation of medical research."

I am not aware of any clear statements on translational research from McCain, though he favors greater funding for NIH, and based on his debate and website, he seems to have a soft spot for autism research. As on other issues, McCain is less willing to commit to a timetable on NIH budget doubling. (photo credit: Thomas Hawk, Wordle of McCain and Obama convention speeches, 2008)

Tuesday, October 14, 2008

Northward Migration?

"Since 2005, we've started seeing the big 20 pharma corporations making investments [in gene therapy]," says a deputy head in European Medicine Agency (EMEA) in the October 2008 issue of Nature Biotechnology ("Ark floats gene therapy's boat, for now," by Randy Osborne). "When you want to know what season is there and when the weather will change, you have to see which birds are flying."

All this should be very encouraging for the field. Yet the story also describes the many travails of companies seeking regulatory approval for their gene transfer products. One is Introgen, which sought approval for its adenovirus-p53 cancer product Advexin. FDA returned Introgen's submission with a "refuse to file" letter indicating that the materials were incomplete. The study on which this filing was based was presented at the American Society of Gene Therapy meeting last Spring. As I indicated in my June 10 posting, a major concern with this study was that its efficacy claims were based on a subgroup analysis of genetic profiles. Others, like TheStreet.com columnist Adam Feuerstein, have been far less guarded in their assessment of Advexin; Feuerstein called Introgen "a living textbook for what investors need to be wary of when considering a biotech investment."

The second product profiled in the Nature Biotechnology story is Ark's Cerepro, which uses herpes simplex virus vectors to deliver a gene, thymidine kinase, to the tumor bed of patients with malignant glioma (a highly aggressive form of brain cancer); the gene then converts a pro-drug, ganciclovir, into a toxin that kills tumor tissue. Ark is reportedly planning to file a license application to EMEA. Preliminary data in a randomized controlled trial against standard of care vs. standard of care + Cerepro indicate a median extension of survival by 42 days (with serious side effects).

One last product profiled briefly is Amsterdam Molecular Therapeutic's product, Glybera, for a very rare genetic disease lipoprotein lipase deficiency. Amsterdam intends to file for licensure "later this year."

The fortunes of clinical gene transfer might indeed be flying North. But with some lead products showing such incremental gains in survival and dependence on combination with standard care, clinical application seems less likely to arrive with a bang than with a modest honk.  (photo credit: denis collette, 2007)

Friday, October 10, 2008

The Problem with Models

Chicago in plastic and balsa. If only animal models were as convincing as the one pictured above from the Museum of Science and Industry. 

The August 7 issue of Nature ran a fascinating feature on how many scientists are reassessing the value of animal models used in neurodegenerative preclinical research ("Standard Model," by Jim Schnabel).

The story centers on the striking failure to translate promising preclinical findings to treatments for various neurodegenerative diseases. In one instance, a highly promising drug, minocycline, actually worsened symptoms in patients with ALS. In other instances, impressive results in mice have not been reproducible. According to the article, a cluster of patient advocacy groups, including organizations like Prize4Life and a non-profit biotechnology company ALS TDI, are spearheading a critical look at standard preclinical models and methodologies.

Much of the report is about limitations of mouse models. Scientists from the Jackson Laboratories (perhaps the world's largest supplier of research mice) warn that many mouse strains are genetically heterogenous; others develop new mutations on breeding. Other problems described in the article: infections that spread in mouse colonies, problems matching sex or litter membership in experimental and control groups, and small sample sizes. The result is Metallica-like levels of noise in preclinical studies. Combined with nonpublication of negative studies, and the result is many false positives.

The article bristles with interesting tidbits. One that struck me is the organizational challenges of changing the culture of model system use. According to the article, many academic researchers and grant referees have yet to warm to criticisms of models, and some scientists and advocates are asking for leadership from the NIH. Another striking point in the piece-alluded to in the article's closing-is a fragmentation of animal models that mirrors personalized medicine.

"Drugs into bodies." That's the mantra of translational research. It is an understandable sentiment, but also pernicious if it means more poorly conceived experiments on dying patients. What is needed is a way to make animal models- and guidelines pertaining to them- as alluring as supermodels. (photo credit: Celikens 2008)

Monday, October 6, 2008

STAIRing at Method in Preclinical Studies

Medical research, we all know, is highly prone to bias. Researchers are, after all, human in their tendencies to mix desire with assessment. So too are trial participants. Since the late 1950s, epidemiologists have introduced a number of practices to clinical research designed to reduce or eliminate sources of bias, including randomization of patients, masking (or "blinding") of volunteers and physician-investigators, and statistical analysis.

In past entries, I have rallied for extending such methodological rigor to preclinical research. This has three defenses. First, phase 1 human trials predicated on weak preclinical evidence are insufficiently valuable to justify their execution. Second, methodologically weak preclinical research is an abuse of animals. Third, publication of methodologically weak studies is a form of "publication pollution."

Two recent publications underscore the need for greater rigor in preclinical studies. The first is a paper in the journal Stroke (published online August 14, 2008; also reprinted in Journal of Cerebral Blood Flow and Metabolism). Many of the paper's authors have doggedly pursued the cause of preclinical methodological rigor in stroke research by publishing a series of meta-analyses of preclinical studies in stroke. In this article, Malcolm Macleod and co-authors outline eight practices that journal editors and referees should look for in reviewing preclinical studies. Many are urged by STAIR (Stroke Therapy Academic Industry Roundtable)– a consortium organized in 1999 to strengthen the quality of stroke research.

Their recommendations are:

1- Animals (precise species, strain, and details should be provided)
2- Sample-size calculation
3- Inclusion and exclusion criteria for animals
4- Randomization of animals
5- Allocation concealment
6- Reporting of animals concealed from analysis
7- Masked outcome assessment
8- Reporting interest conflicts and funding

There's an interesting, implicit claim in this paper: journal editors and referees partly bear the blame for poor methodological quality in preclinical research. In my next post, I will turn to a related news article about preclinical studies in Amyotrophic Lateral Sclerosis. (photo credit: 4BlueEyes, 2006)