Posts made in January, 2017

Questions about Deaths in Cancer Trials using Gene-Altered Cells

Posted on Jan 9, 2017

This article was originally posted on The Center for Genetics and Society’s site here.

In the past month, the media has reported seven patient deaths of subjects enrolled in separate gene therapy clinical trials being conducted by Juno Therapeutics and by Ziopharm Oncology, Inc., both aimed at immunotherapy-based cancer treatments that have sparked widespread hope. Despite these deaths, the trials continue to move forward.

Media coverage of trials related to gene therapy has portrayed the clinical research rollercoaster.  Just this past week, The New York Times ran an unusually lengthy and high-profile series of articles in the Sunday paper about immunotherapy treatments for cancer, some involving genetic modification of immune cells. The articles describe the promising aspects of engineering one’s own immune system to fight cancer, including dramatic stories of tumors “melting away” and promises of complete remission.

Yet commentary on the ethical implications of these events has been scant, and these events raise a number of concerns about what bioethicists call “therapeutic misconception” – vulnerable patients seeking enrollment in a clinical trial with the mistaken belief that the gene therapy is approved by the FDA to be safe and effective. The clinical trial deaths also highlight lingering questions about transparent reporting of adverse events to the FDA and appropriately navigating financial conflicts of interest.  Instead, numerous articles have focused on how these deaths impact the bottom line: corporate stock prices.

The excitement has been building for some time. In June 2015, MIT Technology Review described Juno’s experimental T-cell immunotherapy for leukemia as “Biotech’s Coming Cancer Cure” and profiled the “miracle” recovery of 20-year old leukemia patient Milton Wright III. Wright signed up for the clinical trial because “they hyped it up, like it was going to be amazing” and MIT Technology Review has characterized Juno’s immunotherapy trials as “remarkable.”

Some scientists are hopeful for a breakthrough, particularly for patients whose cancer has returned after multiple rounds of traditional chemotherapy. For vulnerable patients seeking a “miracle cure,” such characterizations blur the distinction between approved therapy and clinical research that may or may not produce a viable therapy. As a disclaimer, I have not seen any of the informed consent documents from Juno or Ziopharm. But whatever these documents say, media descriptions of a “coming cancer cure” make it challenging to fully convey the risks to sick people with few other options who are considering enrolling in clinical trials as a last-ditch treatment effort. This is precisely the kind of situation that the term “therapeutic misconception” addresses.

We must cautiously tread when describing Phase I and Phase II clinical trials to patients who are simultaneously acting as research subjects, and take care not to inflate our words when we discuss this research in the media. Despite the misleading name, these early gene therapy trials are not approved therapies, but experiments to assess safety, dosing tolerability, and effectiveness. The goal for this stage of research is not to provide a treatment for this specific person, but rather to contribute to generalized knowledge. It focuses on asking: Will this method of gene therapy work? Is it safe? Are there adverse risks so severe or frequent which constitute an unacceptable level of risk?

It is not clear whether the patients recognize the uncertainty of benefit, especially when measured against the magnitude of risk. Gene therapy poses a distinct, and an arguably riskier, profile of possible adverse effects compared to drugs alone because it can permanently alter the recipient’s cells and holds the potential for severe latent adverse effects such as cancer, immunologic, neurologic, and autoimmune complications.

When unexpected serious adverse reactions do occur that are related to the trial, the sponsor must report these to the FDA. Several months ago in May 2016, Juno reported one death to the FDA of a subject who was enrolled in one of its CAR-T protocols for leukemia, asserting: “It is not clear what caused the death, and a change at this time is not warranted.” In July, Juno reported two more deaths, this time stating that they resulted from compounding factors (a chemotherapy drug Fludarabine used in conjunction with the CAR-T protocol). Juno subsequently updated its statement, disclosing there have been four total deaths from its CAR-T protocols.

In response, the FDA temporarily (and very briefly) suspended the clinical trial, causing a fleeting plummet in Juno’s stock prices. Juno quickly submitted a modified protocol that removed Fludarabine, updated the trial brochure, and amended the patient consent form to the FDA. The FDA deemed these modifications acceptable and expediently lifted the hold within days, despite the alarming disclosure. Juno’s trial – and stock prices  – were back in business.  Articles (here and here) characterized these deaths and the corresponding swift response as a “bump in the road,” myopically questioning how it would impact the clinical trial progression and corporate financial outlook. Minimizing patient deaths that may have resulted from the gene therapy rather than their underlying illness is dehumanizing and ethically inappropriate, even if we reason that these patients were near the end of life.

One biotech analyst questioned FDA’s decision to quickly lift the clinical trial hold, observing, “They are trying to referee a game while the rules are still being written. And it appears to be causing some deaths that should have been avoided.”

Ziopharm made similar headlines in the past few months relating to its Phase I clinical trials designed for glioblastoma patients. Ziopharm partnered with the synthetic biology company Intrexon, and has been studying a gene therapy technique using a genetically engineered virus that is directly injected into the subject’s tumor. According to Ziopharm, the third subject died 15 days after beginning the trial of an intracranial hemorrhage. Prior to this report, two other enrolled subjects also died, albeit months after the initiation of one of the trials. According to a press release, Ziopharm maintains the intracranial hemorrhage death “is an isolated case” and the other patient deaths were unrelated, and attributed those outcomes to pre-existing illness, stating, “these patients are all, unfortunately, medically fragile.”

The problem with reporting adverse events, including deaths, to the FDA resides in a substantial loophole that awards discretion to the investigator to decide whether the adverse event is serious and whether it reasonably resulted from the gene therapy. Although the investigator theoretically stands in the best position to sort through the noise of the confounding variables of underlying illness or other drugs the subject may be taking, this nonetheless creates a troublesome reliance upon the corporation whose stock price and profitability are tenuously tied to clinical trial performance. This creates an undeniably powerful motivation to shift the blame of any adverse outcomes.

As Professor Osagie K. Obasogie has noted, profit motives remain entrenched in medical research, which can further complicate relationships where industry and medical care become intertwined. The arrangement between Ziopharm and MD Anderson Cancer Center exemplifies such enmeshment: Ziopharm and Intrexon executed a deal with MD Anderson to provide $100 million in stock, and recently appointed MD Anderson physician Dr. Laurence Cooper as Ziopharm’s newly minted CEO.  Similarly, Science’s recent profile of competitor Dr. Carl June’s work at the University of Pennsylvania also flagged the potential conflict of interest arising from its partnership with Novartis to develop gene therapies for which June would hold a financial stake arising from related patents.

Despite assertions that these relationships will be managed according to institutional conflict of interest policies, such heavy financial ties heighten the stakes and necessarily raise concerns about independent judgment and transparency. The call to uphold ethical tenets of research is nothing new, particularly when there is a frantic competition to bring an FDA-approved product to market. Back in 2007, Obasogie raised similar concerns after a patient death in a gene therapy trial for arthritis: “Time is money; in the rush to get products to market, patient safety can inadvertently take a backseat.”

These vulnerable patients have a stake, too. We must ask the right questions to see whether they appreciate the risks they decide to undertake. We must stop blindly accepting these dismissals of deaths and assurances that conflicts of interests are mitigated, especially when there is so much riding on clinical trials’ success.

 

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