SOURCE : BBC
First trial of embryonic stem cells in humans
There are hopes that stem cell therapy can be used to tackle many diseases
US doctors have begun the first official trial of using human embryonic stem cells in patients after getting the green light from regulators.
The Food and Drug Administration has given a license to Geron to use the controversial cells to treat people with spinal injuries.
The cells have the potential to become many of the different cell types found in the body, including nerve cells.
The trials at a hospital in Atlanta will check if the treatment is safe.
Pivotal researchGeron, a biotech company based in "silicon valley" south of San Francisco, has spent $170m on developing a stem cell treatment for spinal cord injury.
The research will use cells coaxed to become nerve cells which are injected into the spinal cord.
In animal trials of the treatment, paralysed rats regained some movement.
But it is not yet known if it will offer any benefit to people with spinal cord injuries.
“Start Quote
End Quote Professor Sir Ian Wilmut MRC Centre for Regenerative MedicineThis is very exciting news, however, it is very important to appreciate that the objective of trials at this stage is to confirm first of all that no harm is done to patients, rather than to look for benefits”
Every year around 12,000 people in the US sustain spinal cord injuries. The most common causes are automobile accidents, falls, gunshot wounds and sports injuries.
In the trial, patients who have sustained such an injury within the last 14 days will be given the experimental stem cell treatment.
Geron president Dr Thomas Okarma said: "When we started working with human embryonic stem cells in 1999, many predicted that it would be a number of decades before a cell therapy would be approved for human clinical trials.
"This accomplishment results from extensive research and development and a succession of inventive steps."
But it will take some time to get the results.
And there are many years of rigorous testing ahead before it can be known if the therapy is safe and effective.
Professor Sir Ian Wilmut, director of the Medical Research Council Centre for Regenerative Medicine at the University of Edinburgh, said: "This is very exciting news, however, it is very important to appreciate that the objective of trials at this stage is to confirm first of all that no harm is done to patients, rather than to look for benefits.
"Once that has been confirmed then the focus moves on to development and assessment of the new treatment."
Ben Sykes, executive director of the UK National Stem Cell Network, said: "This is indeed a significant milestone in our journey towards the promise of stem cell-based medicines.
"The global stem cell and regenerative medicine community will be awaiting the results of this safety trial with much anticipation."
Professor Chris Mason, an expert in regenerative medicine at University College London, said UK researchers hope to follow suit and begin trials next year with a stem cell treatment for age-related macular degeneration - a leading cause of blindness.
Q&A: Stem cells
Embryonic stem cells have the potential to create virtually any human cell or tissueUS doctors have begun the first official trial of using human embryonic stem cells in patients.
What are stem cells?
Most adult cells in the body have a particular purpose which cannot be changed.
For instance, a liver cell is developed to perform specific functions, and cannot be transformed to suddenly take on the role of a heart cell.
Stem cells are different. They are still at an early stage of development, and retain the potential to turn into many different types of cell.
Why are they so useful?
When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialised function.
Scientists believe it should be possible to harness this ability to turn stem cells into a super "repair kit" for the body.
Theoretically, it should be possible to use stem cells to generate healthy tissue to replace that either damaged by trauma, or compromised by disease.
Among the conditions which scientists believe may eventually be treated by stem cell therapy are Parkinson's disease, Alzheimer's disease, heart disease, stroke, arthritis, diabetes, burns and spinal cord damage.
Stem cells may also provide a useful way to test the effects of experimental drugs.
It is also hoped that studying stem cells will provide vital clues about how the tissues of the body develop, and how disease takes hold.
Are there different types of stem cell?
Yes. Scientists believe the most useful stem cells come from the tissue of embyros.
This is because they are pluripotent - they have the ability to become virtually any type of cell within the body.
Stem cells are also found within adult organs. They have not taken on a final role, and have the potential to become any of the major specialised cell types within that organ.
Their role is to maintain the organ in a healthy state by repairing any damage it suffers.
It is thought their potential to become other types of cell is more limited than that of embryonic stem cells. But there is evidence that they are still relatively "plastic".
Is the use of stem cells controversial?
Very. Campaigners are vehemently opposed to the use of embryonic stem cells.
These cells are typically taken from lab-created embryos that are just four or five days old, and are little more than a microscopic ball of cells.
However, opponents argue that all embryos, whether created in the lab or not, have the potential to go on to become a fully fledged human, and as such it is morally wrong to experiment on them.
They strongly advocate the use of stem cells from adult tissue.
Are there safety concerns?
Yes. Some researchers fear that it is possible that stem cell therapy could unwittingly pass viruses and other disease causing agents to people who receive cell transplants.
Some research has also raised the possibility that stem cells may turn cancerous.
Work also still needs to be done to refine the new technique. Similar results were achieved by two teams using a different combination of gene-controlling proteins.
In both cases the success rate in producing new stem cells was also low.
Paralysed man is first to be treated with stem cells from embryo
By Steve Connor, Science EditorTuesday, 12 October 2010
Embryonic stem cells have the proven ability to develop into any of the 200 or more specialised tissues of the body
A patient who was partially paralysed as a result of an injury to the spinal cord has become the first person to be injected with millions of stem cells derived from early human embryos created by IVF.
Geron Corporation, based in Menlo Park, California, said that it has enrolled the first of several patients in a pioneering study of embryonic stem cells. The phase one clinical trial will attempt to assess whether the novel treatment is safe, rather than effective.
Embryonic stem cells have the proven ability to develop into any of the 200 or more specialised tissues of the body, from insulin-making pancreatic cells to the nerve cells of the brain. Scientists believe they could be used to treat many incurable conditions, from spinal injury to Parkinson's disease.
However, there are concerns that the reality may not live up to the hype. As yet, there has been little clinical demonstration that human embryonic stem cells are safe, let alone effective, with concerns that they may lead to cancerous tumours.
Early in 2009, Geron was given a licence by the US Food and Drug Administration (FDA) to carry out the first clinical trial on spinal cord patients. But later in the year the company had to carry out further tests when the FDA became concerned about the growth of cysts in some laboratory animals injected with embryonic stem cells.
Having resolved these difficulties, Geron said it has now enrolled its first patient, who was injected with embryonic stem cells into the spinal cord within 14 days of the injury, a precondition of the licence. Researchers believe that stem cells have the best chance of repairing damaged nerves if the cells are injected as soon as possible after the injury has occurred.
Most spinal cord injuries are the result of bruising to the delicate tissues rather than severance of the nerves. The most common causes are car accidents, falls and sports injuries.
Thomas Okarma, the president and chief executive of Geron, said the start of the trial involving the injection of clinical grade embryonic stem cells into patients with spinal cord injury marks a milestone in stem cell therapies.
"When we started working with human embryonic stem cells in 1999, many predicted that it would be a number of decades before a cell therapy would be approved for human clinical trials," Dr Okarma said.
The patient, who has not been named, is attending the Shepherd Centre, a 132-bed spinal cord and brain injury hospital and clinical research centre in Atlanta, Georgia. The Shepherd Centre is one of several medical institutions in the US that have agreed to be part of the enrolment plan for Geron's clinical trial.
Donald Peck Leslie, medical director of the Shepherd Centre, said: "We are pleased to have our patients participating in this exciting research. Our medical staff will evaluate the patients' progress. We look forward to participating in clinical trials that may help people with spinal cord injury."
Professor Sir Ian Wilmut, director of the MRC's Centre for Regenerative Medicine at the University of Edinburgh, said: "This is very exciting news, however, it is very important to appreciate that the objective at this stage is to confirm first of all that no harm is done to patients, rather than to look for benefits. Once that has been confirmed then the focus moves on to development and assessment of the new treatment."
What are stem cells, and should we be using them?
What are embryonic stem cells?
Cells derived from IVF embryos that are a few days old. The cells have the power to develop into any of the 200-plus specialised tissues of the body, such as heart cells or the nerve cells of the brain.
Why do doctors want to use them?
Embryonic stem cells could be used to mend damaged tissues and organs by replacing the specialised cells that have been lost. It could revolutionise the way medicine is practised in the 21st century, leading to new treatments for a range of incurable disorders, from heart disease to Parkinson's.
Are there any ethical objections?
People who believe that human embryos are individuals with souls object to them being used in this way. Some religious groups, notably the Catholic Church, have been vocal opponents of such research and the former US President George W Bush imposed a moratorium on government funding of embryonic stem cell research.
Are there any scientific objections?
Some scientists are wary about potential cancers that could be generated when stem cells are injected into patients. This is one of the reasons why it has taken so long for the first clinical trial to go ahead.
Why are there no similar clinical trials in Britain?
It takes an enormous amount of money to plan such trials, partly because of the expense of making sure they are safe, and there are more companies willing to undertake this financial risk in the US than here.
Source : The Independent
First patient treated in stem cell study
Monday, October 11, 2010;
Doctors have injected millions of human embryonic stem cells into a patient partially paralyzed by a spinal cord injury, marking the beginning of the first carefully designed attempt to test the promising but controversial therapy, officials announced Monday
The patient was treated Friday at the Shepherd Center, a 132-bed hospital in Atlanta that specializes in spinal cord and brain injuries, according to announcement by the hospital and Geron Corp. of Menlo Park, Calif., which is sponsoring the research.
The hospital is one of seven sites participating in the study, which is primarily aimed at testing whether the therapy is safe. Doctors will also conduct tests to see whether the treatment restores sensation or enables the patient to regain movement. No additional information about the first patient was released.
The milestone was welcomed by scientists eager to finally move the research from the laboratory to the clinic, as well as by advocates for patients and by patients hoping for cures. Although the cells have been tested in animals, and some clinics around the world claim to offer therapies using human embryonic stem cells, the trial is the first to have been vetted by a government entity and aimed at carefully evaluating the strategy. After repeated delays, the Food and Drug Administration gave the go-ahead in July.
But the move was criticized by those with moral objections to any research using cells from human embryos, and it is raising concern even among many proponents. Some argue that the experiments are premature, others question whether they are ethical, and many fear that the trials risk disaster for the field if anything goes awry.
"Without knowing more clinical detail, there's little I can say," said Steve Goldman, chairman of the department of neurology at the University of Rochester in New York. "In more general terms . . . I remain concerned about the long-term safety of unpurified grafts of embryonic stem cell derivatives. Time will tell."
David Prentice, senior fellow for life sciences at the Family Research Council, said: "Geron is helping their stock price, not science and especially not patients. It will be years before there is hard evidence about safety or effectiveness. Adult stem cells have published evidence documenting effective treatment of spinal cord injury."
Supporters of the privately funded research are confident that it has been exhaustively vetted. The FDA has demanded extensive experiments in the laboratory and on animals to provide evidence that the cells hold promise and are safe enough to test in people.
"Initiating the . . . clinical trial is a milestone for the field of human embryonic stem cell-based therapies," said Thomas B. Okarma, Geron's president and chief executive, in a statement. "This accomplishment results from extensive research and development and a succession of inventive steps."
Donald Peck Leslie, Shepherd's medical director, said: "We are pleased to have our patients participating in this exciting research. Our medical staff will evaluate the patients' progress as part of this study. We look forward to participating in clinical trials that may help people with spinal cord injury."
But some scientists worry that if patients are hurt by the cells - or even if there's no hint that the cells help - it could be a devastating blow to the field. They cite the case of Jesse Gelsinger, whose 1999 death from a gene therapy experiment set that once-highly touted field back years.
Safety worries - most prominently fears that the cells could cause tumors - prompted the FDA to repeatedly demand additional data from Geron, including, most recently, assurance that cysts that developed in mice injected with the cells posed no threat.
Although Geron eventually hopes to test the cells for many different medical problems, the first trial will involve 10 patients who were partially paralyzed by a spinal cord injury in the previous one to two weeks. Surgeons injected the first patient with about 2 million "oligodendrocyte progenitor cells," created from embryonic stem cells, in the hopes that the cells will form a restorative coating around the damaged spinal cord. In tests in hundreds of rats, partially paralyzed animals walked.
Spinal cord injuries, however, are highly unpredictable. Patients often improve on their own, for example, making it difficult to evaluate whether the cells had any effect. Some wonder whether trauma victims who have so recently suffered a life-altering injury will agree to the experiments out of desperation without fully grasping the risks. There is also concern that the therapy risks worsening the patients' conditions, perhaps making them fully paralyzed.
But company officials said they are confident. Even if problems occur, research shows that the cells do not leave the site of the injury, indicating that patients would not suffer any ill effects, Okarma said. Extra precautions, including assigning each subject an independent advocate, will guarantee that volunteers fully understand their decisions, he said.
In the meantime, officials at Advanced Cell Technology of Santa Monica, Calif., are hoping for the FDA's go-ahead to start injecting 50,000 to 200,000 cells into the eyes of 12 patients with Stargardt's macular dystrophy. "Retinal pigmented epithelial cells," also made from human embryonic stem cells, should replace those ravaged by the progressive loss of eyesight, which usually begins in childhood. Studies in rats found that the cells helped prevent further vision loss and even restored some sight. The company hopes that the approach will work for many conditions, including macular degeneration, the leading cause of blindness among the elderly.
The announcement comes as the future of federal funding for embryonic stem cell research remains in doubt. A federal judge ruled in August that the Obama administration's more permissive policy for funding the research violated a federal law prohibiting taxpayer money being used for research that involves the destruction of human embryos. The Justice Department is appealing the decision.
Source : The Washington Post
First person treated in milestone stem cell trial
11 October 2010 by Andy Coghlan
A person with spinal injuries today went down in history as the first to receive a treatment derived from human embryonic stem cells (hESCs).
Many people have already been treated with stem cells originating from adult tissue, such as bone marrow, but the trial is the first authorised attempt to treat someone with cells derived from hESCs, the cells in embryos that can grow into all tissues of the body.
Anti-abortion groups oppose such treatments because hESCs can usually be obtained only by destroying a human embryo. But backers point out that the cells have enormous potential for treating disease and regenerating tissue.
Following endless setbacks and delays in authorising the trial, the patient was treated at the Shepherd Center in Atlanta, Georgia.
Surgeons injected millions of oligodendrocyte progenitor cells grown from hESCs into the injury site through a fine needle, hoping the cells would stimulate nerve growth and re-sheathe nerves damaged through the injury. Injured rats treated with the cells recovered some mobility about a month after being treated.
Safety first
The hope is that these progenitor cells, codenamed GRNOPC1 cells, will help the patient overcome paralysis resulting from the injury, although the primary objective of the trial is to make sure the treatment is safe.
"Initiating the GRNOPC1 clinical trial is a milestone for the field of hESC-based therapies," said Thomas Okarma, president of Geron in Menlo Park, California, the company which has spent more than a decade developing treatments derived from hESCs.
Although the trial first received the go-ahead in January last year, it was put on hold the following August by the US Food and Drug Administration, which demanded further evidence that the treatment wouldn't cause cysts like those seen in some animal studies.
Approval was re-issued last August, and the patient whose treatment was announced today is the first to be treated in the seven-centre trial. A spokeswoman at the Shepherd Center said that all details of the person are being kept confidential for now, including their gender and age, and how the injury occurred.
Morale boost
Other stem-cell researchers hailed the news. "This is a significant milestone in our journey towards the promise of stem-cell-based medicines," says Ben Sykes, executive director of the UK National Stem Cell Network. "The global stem-cell and regenerative medicine community will be awaiting the results of this safety trial with much anticipation."
"This is very exciting news," says Ian Wilmut of the University of Edinburgh, UK, and creator of Dolly the cloned sheep. "However, it's very important to appreciate that the objective of trials at this stage is first of all [to ensure] that no harm is done to the patients."
"This first-in-man study marks the dawn of the 'stem-cell age'," says Chris Mason, professor of regenerative medicine at University College London. "This pivotal clinical trial is a major morale boost for scientists, clinicians and, most of all, for patients."
News of the trial is also likely to raise the morale of federally funded researchers at the US National Institutes of Health working on hESCs, as the legality of federal funding for their research is being challenged in court. In August, federally funded work on stem cells was temporarily suspended after a judge ruled that work on hESCs violates a legal amendment in 1995 forbidding funding of any experiments that involve destruction of human embryos.
The injunction was lifted a fortnight later, but only as a temporary measure until the legality of federal funding is resolved once and for all either in a court case or by altering the 1995 amendment.
Source : Newscientist
Stem cell clinical trial aims to combat nerve damage in human tissue
Pioneering treatment given go-ahead in US as researchers inject cells directly into patient's damaged spinal cord
A patient with a damaged spinal cord has become the first to be injected with embryonic stem cells in a landmark clinical trial of the therapy.
The controversial and long-awaited trial was given the green light by the US Food and Drug Administration in January last year, and is being organised by Geron, a biotech company based in California.
Doctors hope that injecting stem cells directly into the spine will help repair damaged nerve cells enough for paralysed people to regain some movement, but such treatments have yet to be tested in humans.
Though preliminary, the launch of the trial marked the "dawn of the stem cell age," according to one British stem cell researcher.
The patient, who has not been named, was treated on Friday at the Shepherd Centre, a specialist spine and brain injury unit in Atlanta, Geron said in a statement released today. The centre is one of seven potential sites in the US that can enroll patients for the trial.
In the trial, patients who have received a spinal injury within the past 14 days will be injected with living cells that are precursors of a kind found in the nervous system. The cells are expected to infiltrate the site of the injury and release chemicals that help repair damaged spinal cord nerves.
Tests in animals show that injections of the cells can improve their ability to walk and move after sustaining an injury.
"When we started working with human embryonic stem cells in 1999, many predicted that it would be a number of decades before a cell therapy would be approved for human clinical trials," said Thomas Okarma, Geron's president and CEO. The trial has triggered objections from some religious groups because the cells are derived from spare embryos created at IVF clinics.
In the phase one trial, doctors will establish only whether the treatment is safe to use. Geron will need to conduct further trials in coming years to assess whether the treatment is effective in repairing spinal cord injuries.
"This first-in-man study marks the dawn of the stem cell age. There are still many years of rigorous testing ahead and no doubt there will be setbacks and failures before we have safe and effective cell-based therapies," said Chris Mason, professor of regenerative medicine at University College London.
"This pivotal clinical trial is a major morale boost for scientists, clinicians and most of all patients by finally commencing the transformation of stem cells from a scientific curiosity into advanced healthcare."
Throughout the trial, doctors will monitor patients to see whether they are regaining sensation or better able to move parts of the body affected by their injury.
Sir Ian Wilmut, director of the MRC Centre for Regenerative Medicine at Edinburgh University, who led the team that created Dolly the sheep, said: "This is very exciting news, however, it is very important to appreciate that the objective of trials at this stage is to confirm first of all that no harm is done to patients, rather than to look for benefits. Once that has been confirmed then the focus moves on to development and assessment of the new treatment."
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