Scientists argue that a study on heart stem cells should be suspended



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A few days after Harvard Medical The school said it has discovered a lot of data falsified or manufactured by the laboratory of a leading cardiology researcher. Doctors and scientists advocate stopping the partially based medical test on his work. They say that sick people should not be subject to the risks of an experiment whose underlying science has been questioned.

As part of the current taxpayer-funded trial, cardiac stem cells are injected into the heart of heart failure patients, in the hope that these cells, alone or in combination with others, will improve the function of heart failure. patient's heart.

The regenerative effects of these cells were first reported Piero Anversa, an influential but controversial scientist whose work has been questioned. Harvard revealed that a multi-year investigation had identified "falsified and / or fabricated data" in 31 documents from its laboratory, without specifying which publications were affected. Last year, Harvard-affiliated Brigham and Women's Hospital, where Antwerpa was working until 2015, reached a $ 10-million settlement with the Department of Justice to resolve allegations that fraudulent data may have been collected. been used by the Antwerpa laboratory. in grant applications for federal funding.

On Wednesday, the New England Journal of Medicine withdrew an article and reported two more with a "concern" to "indicate that the data presented in the articles named above may not be reliable." information on both papers.

The New York Medical College, where formerly worked Anversa, issued a statement in which he stated that "serious concerns" had been raised about a 17-year-old study. He said that an investigation had been opened.

Antwerpa does not participate directly in the heart failure trial, which is managed by a national clinical trial network with $ 63 million in federal funding. But given the turbulence and uncertainty surrounding the work that laid the groundwork for the trial, outside researchers asked for a pause and careful consideration of its relevance. The test carries inherent risks because it requires an invasive biopsy that can lead to serious complications.

A patient died after perforating his heart during a biopsy.

"I think the trial should be interrupted and that an external examination should be performed," said Darryl Davis, a cardiologist at the University of Ottawa Heart Institute. who is studying how to regenerate heart tissue. "The data Antwerpa were part of the reason for being this trial and I think we need to better understand what these cells can actually do before subjecting patients to the risk of undergoing an invasive procedure."

The Antwerpa laboratory performed the basic work in this area and provided cells for a previous clinical trial, cited as evidence in support of the current trial. However, the National Heart, Lung and Blood Institute does not consider the essay to be based on the work of Antwerpa, according to Denis Buxton, director of the Institute's fundamental and early translational research program. Buxton said the trial was based on an idea from Antwerpa's original work that cells secrete various molecules that help regenerate muscle tissue, although this is "a bad effect." characterized for the moment.

"Many preclinical studies have shown improvement in cardiac function and patients with advanced heart failure really have no other treatment option and have poor survival," Buxton said. There is "a compelling need for new treatments that can improve the quality of life of these patients. I think the feeling is that this test has the potential to provide such an option. "

He added that a commission to monitor patient safety in clinical trials would now be tasked with evaluating information on the 31 retractions requested by Harvard, and that patients would be informed of the committee's recommendations.

Antwerpa's lawyer said that his client relied on scientific discoveries in his papers and that Antwerpa The Harvard Inquiry only learned that when a long-time colleague, who had left his lab in 2013, had tampered with the images. Antwerpa says that in many cases these images can be replaced by correct images and that the results will still be valid, said his lawyer.

"There is nothing wrong with c-kit-positive cardiac stem cells, and the trial will answer questions about their efficacy in patients," Antwerpa said in an email.

Antwerpa's work expanded in the excitement of stem cells in the early 2000s. Antwerpa and his colleagues discovered that a type of cardiac cell called c-kit cells were able to give birth to the heart muscle, opening up new possibilities to help heal patients after a heart attack or to reverse the heart attack. heart failure.

The discovery quickly led to clinical trials. The current trial, called CONCERT-HF, is based in part on an earlier clinical trial in which the Antwerpa laboratory had created c-kit cells to infuse into patients' hearts. The report of the results of this trial is now eclipsed by questions about the integrity of images Stem cells created and characterized in the laboratory of Antwerp in Boston, then shipped to Louisville, where they were placed in patients.

Roberto Bolli, a cardiologist at the University of Louisville who led the trial, told The Washington Post that his team's work had nothing to do with cell manufacturing in Boston. He still does not have enough information about the problems in the Antwerpa laboratory to know if they affect the cells provided to patients.

"This is obviously a major concern and we are trying to clarify this important issue," said Bolli.

The National Institute of Heart, Lungs and Blood said that CONCERT was based not on the explanation of Antwerpa explaining the functioning of the c-kit cells, but on an alternative mechanism that has is proven, other researchers, not affiliated with the laboratory of Antwerpa, have discovered that cells do not turn into heart muscle, and instead die or melt with other cells. To explain the effects of cells on heart function in animal studies, some researchers now say that The c-kit cells do not regenerate themselves but secrete various substances, exerting what are called "paracrine effects".

Anversa told the Post Office that the CONCERT trial is based on his work and In a phone interview, he said, "I'm not sure why the trial should be stopped."

In the CONCERT trial, cells are taken from the heart and bone marrow of patients. Two types of stem cells are made from these cells and then reinjected into the patient's body. Patients are randomized into four different groups receiving c-kit cells, bone marrow derived cells, both types or placebo. The patient's death occurred after a biopsy of the person's cardiac cells and before the implantation of the stem cells.

"I think it's time to stop and evaluate things like the CONCERT trial," said Deepak Srivastava, president of the Gladstone Institutes and president-elect of the International Society for Research on the Humanities. stem cells. "And if there is no basis for that, I think in most areas, most trials of this type would be interrupted."

Elizabeth McNally, a cardiologist and director of the Center for Genetic Medicine at Northwestern University's Feinberg School of Medicine, said that she herself was excited by the discoveries of the Antwerpa laboratory, but then had trouble reproducing them. -even. She described a "religious fervor" that settled in those who believed that c-kit cells regenerated the heart. The researchers looked for factors that may be responsible for what she described as "minimal to nonexistent" effects.

"It's disappointing that it has taken so many years," McNally said. "The question is whether the trial should even continue, and I think at the highest level, the people who support it should really be looking at it."

Charles Murry, director of the Institute for Stem Cell Research and Regenerative Medicine at the University of Washington, said he was concerned about the safety of patients participating in the trial.

"Given that the scientific premise of this test is no longer valid, there does not seem to be any potential benefit to justifying the risk," Murry said. I said. "If I was conducting this trial, I think I would stop it based on these recent developments."

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