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The Food and Drug Administration (FDA) approved the first clinical trial in the United States involving human embryonic stem cells on January 23, 2009. Geron Corporation, a biotechnology company located in Menlo Park, California, was originally planned to enroll ten patients with spinal injuries umbilical cord to participate in the trial. The company hopes that GRNOPC1, a product derived from human embryonic stem cells, will stimulate nerve growth in patients with debilitating damage to the spinal cord. Experiments started in 2010 after being delayed by the FDA because cysts were found in mice injected with these cells, and safety issues increased.


Video Human embryonic stem cells clinical trials



Proses persetujuan FDA

In the United States, the FDA must approve all clinical trials involving newly developed drugs. Researchers must complete the Investigational New Drug (IND) application for FDA approval. The IND applications typically include data from animal studies and toxicology where drug safety is tested, drug-making information explaining how and where the drug will be produced, and a detailed research protocol stating who will be included in the study, how the drug will be administered and how the participants will be approved. Tests for new drugs must be successful through three phases of research before the drug can be marketed to the public. In Phase I trials, drug safety was tested on a small group of participants. The effectiveness of the drug was tested during a Phase II trial with a larger number of participants. The Phase III trial, involving 1,000-3,000 participants, analyzed the effectiveness, determined side effects and compared the results of new drugs with similar drugs in the market. Additional phase, Phase IV, including to keep getting information after the drug is in the market. The IND Geron application for the GRNOPC1 clinical trials, nearly 28,000 pages in length, is one of the most extensive applications ever submitted to the FDA.

Maps Human embryonic stem cells clinical trials



Pre-clinical data

Before Geron can test GRNOPC1 in humans, animal testing should be done. At the University of California at Irvine, Dr. Hans Keirstead and Dr. Gabriel Nistor, credited with the technique used to develop oligodendrocytes from human embryonic stem cells, injected cells into mice with spinal cord injuries. Rat condition improved after treatment.

Recent Breakthroughs with Induced Pluripotent Stem Cells Biology Bytes
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Spinal Geron Spinal Injury Experiments

The first patient, identified in an article by the Washington Post as Timothy J. Atchison of Alabama, was enrolled in the hearing in October 2010. The patient was treated at Shepherd Center in Atlanta, GA just two weeks after he suffered a spinal cord injury. in a car accident. The Shepherd Center and six other spinal centers were recruited by Geron to participate in clinical trials. The Washington Post reports that Atchison "has begun to get a bit of a sensation: He can feel relief when he lifts the bowling ball out of his lap and sees discomfort as he pulls his hair at some of his legs and has also strengthened his stomach." Atchison underwent therapy at Shepherd Center for three months before returning to Alabama.

Although Geron initially aimed to register ten patients in the trial, only three additional patients were added after Atchison. As determined by Geron, eligible patients should have a complete spinal cord injury within seven to fourteen days prior to enrollment. In addition, patients must be between the ages of 18 and 65 and can not have a history of malignancy, significant organ damage, pregnancy or lactation, unable to communicate or participate in other experimental procedures. Participants received one shot of GRNOPC1 containing about 2 million cells. Although the trial has officially ended, Geron will continue to monitor participants for fifteen years.

Although no official results from the trial were published, preliminary results from clinical trials were presented at the American Congress of Rehabilitation Medicine (ACRM) conference in October 2011. No participants had serious adverse events, although nausea and low magnesium were reported.. In addition, no changes in the spinal cord or neurologic conditions were found.

After investing millions of dollars in research leading to this trial, Geron Corporation suspended research in November 2011 to focus on cancer research. John Scarlett, Geron's chief executive, said: "In the current environment of capital scarcity and uncertain economic conditions, we intend to focus our resources on advancing two new oncology drug candidates and promising us." The company's shares fell drastically to $ 1.50 per share from $ 2.28 per share when news about the suspension of the experiment became public. A company spokeswoman said that Geron would save money by ending the trial despite losing investors. Because many believe Geron's trial offers hope for advancing knowledge related to stem cells and their potential use, there is disappointment in the scientific community when trials are cut short. An article in the Bioethics Forum, a publication produced by The Hastings Center, states, "It is one thing to close a trial for further registration for scientific reasons, such as problems with experimental design, or for ethical reasons, such as unexpected seriousness hazard risk for participants.This is another matter to close the court for business reasons, such as increasing profit margins. "

In 2013, Geron's stem cell assets were acquired by BioTime biotechnology, led by CEO Michael D. West, founder of Geron and former Chief Scientific Officer of Advanced Cell Technology. BioTime shows that it plans to restart a stem cell-based clinical trial for spinal cord injury.

ACT Stargardt macular dystrophy and age-related macular degeneration clinical trials

Two clinical trials involving human embryonic stem cell derivatives were approved in 2010. Advanced Cell Technology (ACT), located in Marlborough, Massachusetts, led a trial aimed at improving the patient's vision with Stargardt's Macular Dystrophy and Degeneration of Dry Age-Related Macules. Initially, twelve patients were estimated enrolled in three US hospitals; Participating institutions include the Casey Eye Institute in Portland, Oregon, University of Massachusetts Memorial Medical Center in Worchester, Massachusetts, and New Jersey Medical School in Newark, New Jersey. The patient's eyes are injected with pigmented retinal epithelial cells derived from human embryonic stem cells. While no definitive findings from this study have been produced, an article published in the Lancet in January 2012 states that preliminary findings seem promising. In this article, the results of two patients treated as part of the trial were discussed. During the trial, the patient's eyesight worsened, and no negative side effects were reported.

Phase I/II clinical trials involving retinal pigment epithelial (RPE) cells, derived from human embryonic stem cells, for the treatment of severe myopia were approved in February 2013.

Human mesenchymal stem cells - current trends and future ...
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ViaCyte Beta cells derived from human stem cells for the treatment of Diabetes Clinical Trial

The FDA approved a phase I clinical trial with ViaCyte beta cells derived from human embryonic stem cells for the treatment of diabetes in August 2014. The cells will be delivered in immunoprotective capsules and pre-clinical results in animal models show remission symptoms within months. The company reported successful cell transplants in the first of 40 patients to be treated under trial at the end of October 2014.

Embryonic stem cell - Wikipedia
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Future funding

As state funding for human embryonic stem cell research grows, there appears to be more support for state-sponsored clinical trials. In 2010, California committed fifty million dollars for initial clinical trials. Although an approved trial should be conducted in California, scientists hope that this funding will enhance future research in the field.

Nobelist Calls Macular Degeneration Trials “One of Most Successful ...
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See also

  • BioTime
  • Induction of stem cells
  • Michael D. West
  • Retinal pigment epithelium
  • Research on spinal cord injury

Second Ever Clinical Trial Approved with Embryonic Stem Cells ...
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References

Source of the article : Wikipedia

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