Saturday, April 08, 2006

The TGN 1412 Trial "Raises a Number of Big Red Flags"

We previously posted about the disastrous trial, implemented by Parexel International , of a new monoclonal antibody designated TGN 1412, manufactured by TeGenero AG. All six healthy volunteers who got the antibody soon became critically ill (see our most recently here). The International Herald Tribune has done some investigative reporting on this trial.

First, the Tribune confirmed that TeGenero, the manufacturer of TGN 1412, was aware prior to the trial of the possibility that subjects might undergo "cytokine release syndrome" after taking the drug. This syndrome had apparently been observed in some animal testing, although the species of primates tested did not manifest the syndrome. TeGenero, however, felt that this reaction was "not expected," in the human trial.

The Tribune interviewed a survivor of the trial, who stated:
  • He believed "he was participating in a fairly standard trial of a painkiller like ibuprofen, for arthritis."
  • He said that "the novelty of TGN 1412 never came up in upbeat pre-trial briefing, adding: "I had no idea it altered the immune system.'"
  • "At Parexel's orientation meeting there was little time to read the study's 11-page consent form before signing, Rob O. said. Headaches and bruising were listed as potential side effects, as well as the possibility of a severe allergy. But that risk was downplayed."
  • Once the trial was underway, the investigators continued to dose subjects even after the first subjects had started to experience adverse effects. "About the time Rob. O's infusion started, at 9:10 am, the first patient had actually passed out in the adjacent room...." charged one of the subjects' attorneys.
  • Since the trial, "the companies [TeGenero and Parexel] have been unwilling to meet with the trial subjects or provide more data...."
The Tribune quoted Dr Michael Ehrenstein of University College London, who said that human research on TGN 1412 was "a high risk strategy." Michael Goodyear, described as an oncologist and medical ethicist at Dalhousie University, Halifax, Nova Scotia, Canada, said that the conduct of the trial "raises a number of big red flags."
Nonetheless, Dr Ezekiel Emanuel, Chief of Clinical Bioethics at the US National Institutes of Health (NIH) , said "This is a terrible tragic event but so far I don't see any clear ethical problems." (Note that Emanuel formerly expressed indignation when the NIH made conflict of interest rules more stringent, so that his secretary would no longer be allowed to keep stock holdings in health care companies worth more than US $15,000, as noted in this post.)
In my humble opinion, this newspaper article raises further serious questions about whether research subjects were adequately informed about the nature of the trial and its possible risks, and why the investigators continued to administer the drug after the first subjects had begun to experience adverse effects.
Hopefully, further investigations will afford more transparency, and will lead to improved conduct of trials that put the interests of patients ahead of the imperative to "speed your product through clinical development." (The latter phrase is currently a promise made by Parexel on its web-site.)

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