by Lauren Hammit
A novel technique created at UCSF to deliver a growth factor directly to brain cells has shown promising results in treating Parkinson’s symptoms and could enter human clinical trials as early as next year.
The technique is part of an experimental treatment called gene therapy, which is considered a hopeful medical advance for neurodegenerative diseases such as Parkinson’s. Gene therapy involves introducing genetic material into a cell to cause the expression of a particular protein that can replace a missing or defective protein responsible for disease.
The UCSF team demonstrated for the first time that the infusion system they designed successfully spread a targeted protein to critical regions in the primate brain. This resulted, on average, in a 50 percent improvement of symptoms that continued out to two years.
“The approach is among the first shown to be beneficial to animals after they have already developed signs of Parkinson’s,” said Krystof Bankiewicz, MD, PhD, Kinetics Foundation Chair in Translational Research and professor of Neurological Surgery at UCSF. “Our ultimate goal is to reverse this disease in patients, and we hope this method will enable doctors to do exactly that.”
Findings are published online and in the July 14, 2010, issue of the Journal of Neuroscience.
In addition to an improvement in Parkinson’s symptoms, the treated animals also maintained a higher density of neurons that produce the brain chemical dopamine – the same neurons that disappear in Parkinson’s disease. Live imaging of the brain by positron emission tomography (PET) scanning, which has been used to gauge treatment effects in clinical studies of Parkinson’s, showed that those neurons remained active.
“The scans enabled us to see where the protein went – and just as hoped, it had been taken up by neurons and transported along nerve fibers to where it was needed, the substantia nigra.” Bankiewicz said. Parkinson’s disease attacks the substantia nigra, which is a part of the brain that controls movement.
A clinical trial is planned to test the safety of the method, according to the National Institutes of Neurological Disorders and Stroke, which funded this research. In a workup for the trial, the National Institutes of Health Rapid Access to Interventional Development (NIH RAID) program is supporting additional toxicity studies, as well as the production of clinical grade virus.
Saturday, July 24, 2010
Saturday, July 17, 2010
Treatments and drugs
By Mayo Clinic staff
There's no cure for Parkinson's disease, but medications can help control some of the symptoms of Parkinson's disease, and in some case, surgery may be helpful. Your doctor may recommend lifestyle changes, such as physical therapy, a healthy diet and exercise, in addition to medications.
Medications
Medications can help manage problems with walking, movement and tremor by increasing the brain's supply of dopamine. However, taking dopamine itself is not helpful, because it's unable to enter your brain.
Your initial response to Parkinson's treatment can be dramatic. Over time, however, the benefits of drugs frequently diminish or become less consistent, although symptoms can usually still be fairly well controlled.
Examples of medication your doctor may prescribe include:
Levodopa. The most effective Parkinson's drug is levodopa, which is a natural substance in the body. When taken by mouth in pill form, it passes into the brain and is converted to dopamine. Levodopa is combined with carbidopa to create the combination drug, Sinemet. The carbidopa protects levodopa from premature conversion to dopamine outside the brain; in doing that, it also prevents nausea. In Europe, levodopa is combined with a similar substance, benserazide, and is marketed as Madopar.
As the disease progresses, the benefit from levodopa may become less stable, with a tendency to wax and wane ("wearing off"). This then requires medication adjustments. Levodopa side effects include involuntary movements called dyskinesia. These resolve with dose reduction, but sometimes at the expense of reduced parkinsonism control. Like other Parkinson's drugs, it may also lower your blood pressure when standing.
Dopamine agonists. Unlike levodopa, these drugs aren't changed into dopamine. Instead, they mimic the effects of dopamine in the brain and cause neurons to react as though dopamine is present. They are not nearly as effective in treating the symptoms of Parkinson's disease. However, they last longer and are often used to smooth the sometimes off-and-on effect of levodopa.
This class includes pill forms of dopamine agonists, such as pramipexole (Mirapex) and ropinirole (Requip). A short-acting injectable dopamine agonist, apomorphine (Apokyn), is used for quick relief.
The side effects of dopamine agonists include hallucinations, sleepiness, water retention and low blood pressure when standing. These medications may also increase your risk of compulsive behaviors such as hypersexuality, compulsive gambling and compulsive overeating. If you are taking these medications and start behaving in a way that's out of character for you, talk to your doctor.
* MAO B inhibitors. These types of drugs, including selegiline (Eldepryl) and rasagiline (Azilect), help prevent the breakdown of both naturally occurring dopamine and dopamine formed from levodopa. They do this by inhibiting the activity of the enzyme monoamine oxidase B (MAO B) — an enzyme that metabolizes dopamine in the brain. Side effects are rare but may include confusion, headache, hallucinations and dizziness. These medications can't be used in combination with other antidepressants, the antibiotic ciprofloxacin (Cipro), the herb St. John's wort or certain narcotics. Check with your doctor before taking any additional medications with an MAO inhibitor.
* Catechol O-methyltransferase (COMT) inhibitors. These drugs prolong the effect of carbidopa-levodopa therapy by blocking an enzyme that breaks down levodopa. Tolcapone (Tasmar) has been linked to liver damage and liver failure, so it's normally used only in people who aren't responding to other therapies. Entacapone (Comtan) doesn't cause liver problems and is now combined with carbidopa and levodopa in a medication called Stalevo. However, it may worsen other levodopa side effects, such as involuntary movements (dyskinesias), nausea, confusion or hallucinations. It may cause urine discoloration.
* Anticholinergics. These drugs have been used for many years to help control the tremor associated with Parkinson's disease. A number of anticholinergic drugs, such as benztropine (Cogentin) and trihexyphenidyl, are available. However, their modest benefits are often offset by side effects such as impaired memory, confusion, constipation, dry mouth and eyes, and impaired urination.
* Glutamate (NMDA) blocking drugs. Doctors may prescribe amantadine (Symmetrel) alone to provide short-term relief of mild, early-stage Parkinson's disease. It also may be added to carbidopa-levodopa therapy for people in the later stages of Parkinson's disease, especially if they have problems with involuntary movements (dyskinesia) induced by carbidopa-levodopa. Side effects include a purple mottling of the skin and, sometimes, hallucinations.
Physical therapy
Exercise is important for general health, but especially for maintaining function in Parkinson's disease. Physical therapy may be advisable and can help improve your mobility, range of motion and muscle tone. Although specific exercises can't stop the progress of the disease, maintaining muscle strength and agility can help counter some of the progressive tendencies of the disease and also allow you to feel more confident and capable. A physical therapist can also work with you to improve your gait and balance. A speech therapist or speech pathologist can improve problems with speaking and swallowing.
Surgery
Deep brain stimulation is a surgical procedure used to treat Parkinson's disease. It involves implanting an electrode deep within the parts of your brain that control movement. The amount of stimulation delivered by the electrode is controlled by a pacemaker-like device placed under the skin in your upper chest. A wire that travels under your skin connects the device, called a pulse generator, to the electrodes.
Deep brain stimulation is most often used for people with advanced Parkinson's disease who have unstable medication (levodopa) responses. It can stabilize medication fluctuations and reduce or eliminate involuntary movements (dyskinesia). Tremor is especially responsive to this therapy.
Serious risks of this procedure are uncommon, but include brain hemorrhage or stroke. Infection is also a risk, and sometimes requires parts of the device to be replaced. Deep brain stimulation isn't beneficial for people who don't respond to carbidopa-levodopa.
There's no cure for Parkinson's disease, but medications can help control some of the symptoms of Parkinson's disease, and in some case, surgery may be helpful. Your doctor may recommend lifestyle changes, such as physical therapy, a healthy diet and exercise, in addition to medications.
Medications
Medications can help manage problems with walking, movement and tremor by increasing the brain's supply of dopamine. However, taking dopamine itself is not helpful, because it's unable to enter your brain.
Your initial response to Parkinson's treatment can be dramatic. Over time, however, the benefits of drugs frequently diminish or become less consistent, although symptoms can usually still be fairly well controlled.
Examples of medication your doctor may prescribe include:
Levodopa. The most effective Parkinson's drug is levodopa, which is a natural substance in the body. When taken by mouth in pill form, it passes into the brain and is converted to dopamine. Levodopa is combined with carbidopa to create the combination drug, Sinemet. The carbidopa protects levodopa from premature conversion to dopamine outside the brain; in doing that, it also prevents nausea. In Europe, levodopa is combined with a similar substance, benserazide, and is marketed as Madopar.
As the disease progresses, the benefit from levodopa may become less stable, with a tendency to wax and wane ("wearing off"). This then requires medication adjustments. Levodopa side effects include involuntary movements called dyskinesia. These resolve with dose reduction, but sometimes at the expense of reduced parkinsonism control. Like other Parkinson's drugs, it may also lower your blood pressure when standing.
Dopamine agonists. Unlike levodopa, these drugs aren't changed into dopamine. Instead, they mimic the effects of dopamine in the brain and cause neurons to react as though dopamine is present. They are not nearly as effective in treating the symptoms of Parkinson's disease. However, they last longer and are often used to smooth the sometimes off-and-on effect of levodopa.
This class includes pill forms of dopamine agonists, such as pramipexole (Mirapex) and ropinirole (Requip). A short-acting injectable dopamine agonist, apomorphine (Apokyn), is used for quick relief.
The side effects of dopamine agonists include hallucinations, sleepiness, water retention and low blood pressure when standing. These medications may also increase your risk of compulsive behaviors such as hypersexuality, compulsive gambling and compulsive overeating. If you are taking these medications and start behaving in a way that's out of character for you, talk to your doctor.
* MAO B inhibitors. These types of drugs, including selegiline (Eldepryl) and rasagiline (Azilect), help prevent the breakdown of both naturally occurring dopamine and dopamine formed from levodopa. They do this by inhibiting the activity of the enzyme monoamine oxidase B (MAO B) — an enzyme that metabolizes dopamine in the brain. Side effects are rare but may include confusion, headache, hallucinations and dizziness. These medications can't be used in combination with other antidepressants, the antibiotic ciprofloxacin (Cipro), the herb St. John's wort or certain narcotics. Check with your doctor before taking any additional medications with an MAO inhibitor.
* Catechol O-methyltransferase (COMT) inhibitors. These drugs prolong the effect of carbidopa-levodopa therapy by blocking an enzyme that breaks down levodopa. Tolcapone (Tasmar) has been linked to liver damage and liver failure, so it's normally used only in people who aren't responding to other therapies. Entacapone (Comtan) doesn't cause liver problems and is now combined with carbidopa and levodopa in a medication called Stalevo. However, it may worsen other levodopa side effects, such as involuntary movements (dyskinesias), nausea, confusion or hallucinations. It may cause urine discoloration.
* Anticholinergics. These drugs have been used for many years to help control the tremor associated with Parkinson's disease. A number of anticholinergic drugs, such as benztropine (Cogentin) and trihexyphenidyl, are available. However, their modest benefits are often offset by side effects such as impaired memory, confusion, constipation, dry mouth and eyes, and impaired urination.
* Glutamate (NMDA) blocking drugs. Doctors may prescribe amantadine (Symmetrel) alone to provide short-term relief of mild, early-stage Parkinson's disease. It also may be added to carbidopa-levodopa therapy for people in the later stages of Parkinson's disease, especially if they have problems with involuntary movements (dyskinesia) induced by carbidopa-levodopa. Side effects include a purple mottling of the skin and, sometimes, hallucinations.
Physical therapy
Exercise is important for general health, but especially for maintaining function in Parkinson's disease. Physical therapy may be advisable and can help improve your mobility, range of motion and muscle tone. Although specific exercises can't stop the progress of the disease, maintaining muscle strength and agility can help counter some of the progressive tendencies of the disease and also allow you to feel more confident and capable. A physical therapist can also work with you to improve your gait and balance. A speech therapist or speech pathologist can improve problems with speaking and swallowing.
Surgery
Deep brain stimulation is a surgical procedure used to treat Parkinson's disease. It involves implanting an electrode deep within the parts of your brain that control movement. The amount of stimulation delivered by the electrode is controlled by a pacemaker-like device placed under the skin in your upper chest. A wire that travels under your skin connects the device, called a pulse generator, to the electrodes.
Deep brain stimulation is most often used for people with advanced Parkinson's disease who have unstable medication (levodopa) responses. It can stabilize medication fluctuations and reduce or eliminate involuntary movements (dyskinesia). Tremor is especially responsive to this therapy.
Serious risks of this procedure are uncommon, but include brain hemorrhage or stroke. Infection is also a risk, and sometimes requires parts of the device to be replaced. Deep brain stimulation isn't beneficial for people who don't respond to carbidopa-levodopa.
Saturday, July 10, 2010
Top Ten Things to Know About Stem Cell Treatments
by Juan Munevar
There are different types of stem cells—each with their own purpose.
There are many different types of stem cells that come from different places in the body or are formed at different times in our lives. These include embryonic stem cells that exist only at the earliest stages of development and various types of ‘tissue-specific’ or ‘adult’ stem cells that appear during fetal development and remain in our bodies throughout life.
Our bodies use different types of tissue-specific stem cells to fit a particular purpose. Tissue-specific stem cells are limited in their potential and largely make the cell types found in the tissue from which they are derived. For example, the blood-forming stem cells (or hematopoietic stem cells) in the bone marrow regenerate the blood, while neural stem cells in the brain make brain cells. A neural stem cell won’t spontaneously make a blood cell and likewise a hematopoietic stem cell won’t spontaneously make a brain cell. Thus, it is unlikely that a single cell type could be used to treat a multitude of unrelated diseases that involve different tissues or organs. Be wary of clinics that offer treatments with stem cells that originate from a part of the body that is different from the part being treated.
2. A single stem cell treatment will not work on a multitude of unrelated diseases or conditions.
As described above, each type of stem cell fulfills a specific function in the body and cannot be expected to make cell types from other tissues. Thus, it is unlikely that a single type of stem cell treatment can treat multiple unrelated conditions, such as diabetes and Parkinson’s disease. The underlying causes are very different and different cell types would need to be replaced to treat each condition. It is critical that the cell type used as a treatment be appropriate to the specific disease or condition.
Embryonic stem cells may one day be used to generate treatments for a range of human diseases. However, embryonic stem cells themselves cannot directly be used for therapies as they would likely cause tumors and are unlikely to become the cells needed to regenerate a tissue on their own. They would first need to be coaxed to develop into specialized cell types before transplantation. A major warning sign that a clinic may not be credible is when treatments are offered for a wide variety of conditions but rely on a single cell type.
3. Currently, there are very few widely accepted stem cell therapies.
The range of diseases where stem cell treatments have been shown to be beneficial in responsibly conducted clinical trials is still extremely restricted. The best defined and most extensively used is blood stem cell transplantation to treat diseases and conditions of the blood and immune system, or to restore the blood system after treatments for specific cancers. Some bone, skin and corneal diseases or injuries can be treated with grafting of tissue that depends upon stem cells from these organs. These therapies are also generally accepted as safe and effective by the medical community.
4. Just because people say stem cells helped them doesn’t mean they did.
There are three main reasons why a person might feel better that are unrelated to the actual stem cell treatment: the ‘placebo effect’, accompanying treatments, and natural fluctuations of the disease or condition. The intense desire or belief that a treatment will work can cause a person to feel like it has and to even experience positive physical changes, such as improved movement or less pain. This phenomenon is called the placebo effect. Even having a positive conversation with a doctor can cause a person to feel improvement. Likewise, other techniques offered along with stem cell treatment—such as changes to diet, relaxation, physical therapy, medication, etc.—may make a person feel better in a way that is unrelated to the stem cells. Also, the severity of symptoms of many conditions can change over time, resulting in either temporary improvement or decline, which can complicate the interpretation of the effectiveness of treatments. These factors are so widespread that without testing in a controlled clinical study, where a group that receives a treatment is carefully compared against a group that does not receive this treatment, it is very difficult to determine the real effect of any therapy. Be wary of clinics that measure or advertise their results primarily through patient testimonials.
5. A large part of why it takes time to develop new therapies is that science itself is a long and difficult process.
Science, in general, is a long and involved process. Understanding what goes wrong in disease or injury and how to fix it takes time. New ideas have to be tested first in a research laboratory, and many times the new ideas don’t work. Even once the basic science has been established, translating it into an effective medical treatment is a long and difficult process. Something that looks promising in cultured cells may fail as a therapy in an animal model and something that works in an animal model may fail when it is tried on humans. Once therapies are tested in humans, ensuring patient safety becomes a critical issue and this means starting with very few people until the safety and side effects are better understood.
6. To be used in treatments, stem cells will have to be instructed to behave in specific ways.
Bone marrow transplantation is typically successful because we are asking the cells to do exactly what they were designed to do, make more blood. For other conditions, we may want the cells to behave in ways that are different from how they would ordinarily work in the body. One of the greatest barriers to the development of successful stem cell therapies is to get the cells to behave in the desired way. Also, once transplanted inside the body the cells need to integrate and function in concert with the body’s other cells. For example, to treat many neurological conditions the cells we implant will need to grow into specific types of neurons, and to work they will also have to know which other neurons to make connections with and how to make these connections. We are still learning about how to direct stem cells to become the right cell type, to grow only as much as we need them to, and the best ways to transplant them. Discovering how to do all this will take time. Be wary of claims that stem cells will somehow just know where to go and what to do to treat a specific condition.
7. Just because stem cells came from your body doesn’t mean they are safe.
Every medical procedure has risks. While you are unlikely to have an immune response to your own cells, the procedures used to acquire, grow and deliver them are potentially risky. As soon as the cells leave your body they may be subjected to a number of manipulations that could change the characteristics of the cells. If they are grown in culture (a process called expansion), the cells may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types you need. The cells may become contaminated with bacteria, viruses or other pathogens that could cause disease. The procedure to either remove or inject the cells also carries risk, from introducing an infection to damaging the tissue into which they are injected.
8. There is something to lose by trying an unproven treatment.
Some of the conditions that clinics claim are treatable with stem cells are considered incurable by other means. It is easy to understand why people might feel they have nothing to lose from trying something even if it is unproven. However, there are very real risks of developing complications, both immediate and long-term, while the chance of experiencing a benefit is likely very low. In one publicized case, a young boy developed brain tumors as a result of a stem cell treatment. Participating in an unproven treatment may make a person ineligible to participate in upcoming clinical trials (see also number 9). Where cost is high, there may be long-term financial implications for patients, their families and communities. If travel is involved there are additional considerations, not the least of which is being away from family and friends.
9. An experimental treatment offered for sale is not the same as a clinical trial.
The fact that a procedure is experimental does not automatically mean that it is part of a research study or clinical trial. A responsible clinical trial can be characterized by a number of key features. There is preclinical data supporting that the treatment being tested is likely to be safe and effective. Before starting, there is oversight by an independent group such as an Institutional Review Board or medical ethics committee that protect patients’ rights, and in many countries the trial is assessed and approved by a national regulatory agency, such as the European Medicines Agency (EMA) or the U.S. Food and Drug Administration (FDA). The study itself is designed to answer specific questions about a new treatment or a new way of using current treatments, often with a control group to which the group of people receiving the new treatment is compared. Typically, the cost of the new treatment and trial monitoring is defrayed by the company developing the treatment or by local or national government funding. Beware of expensive treatments that have not passed successfully through clinical trials.
Responsibly-conducted clinical trials are critical to the development of new treatments as they allow us to learn whether these treatments are safe and effective. The ISSCR supports participation in responsible clinical trials after careful consideration of the issues highlighted on this site and in discussion with a trusted physician.
10. Stem cell science is constantly moving forward.
Stem cell science is extraordinarily promising. There have been great advances in treating diseases and conditions of the blood system using blood-forming stem cells, and these show us just how powerful stem cell therapies can be. Scientists all over the world are researching ways to harness stem cells and use them to learn more about, to diagnose, and to treat various diseases and conditions. Every day scientists are working on new ways to shape and control different types of stem cells in ways that are bringing us closer to developing new treatments. Many potential treatments are currently being tested in animal models and some have already been brought to clinical trials. In February 2010 the British company ReNeuron announced it had been approved to conduct a Phase I clinical trial of a neural stem cell treatment for stroke. The first embryonic stem cell-based treatment for acute spinal cord injury is currently under review by the U.S. Food and Drug Administration (FDA) and will hopefully move into clinical trials soon. Although it is sometimes hard to see, stem cell science is moving forward. We are tremendously optimistic that stem cell therapies will someday be available to treat a wide range of human diseases and conditions.
There are different types of stem cells—each with their own purpose.
There are many different types of stem cells that come from different places in the body or are formed at different times in our lives. These include embryonic stem cells that exist only at the earliest stages of development and various types of ‘tissue-specific’ or ‘adult’ stem cells that appear during fetal development and remain in our bodies throughout life.
Our bodies use different types of tissue-specific stem cells to fit a particular purpose. Tissue-specific stem cells are limited in their potential and largely make the cell types found in the tissue from which they are derived. For example, the blood-forming stem cells (or hematopoietic stem cells) in the bone marrow regenerate the blood, while neural stem cells in the brain make brain cells. A neural stem cell won’t spontaneously make a blood cell and likewise a hematopoietic stem cell won’t spontaneously make a brain cell. Thus, it is unlikely that a single cell type could be used to treat a multitude of unrelated diseases that involve different tissues or organs. Be wary of clinics that offer treatments with stem cells that originate from a part of the body that is different from the part being treated.
2. A single stem cell treatment will not work on a multitude of unrelated diseases or conditions.
As described above, each type of stem cell fulfills a specific function in the body and cannot be expected to make cell types from other tissues. Thus, it is unlikely that a single type of stem cell treatment can treat multiple unrelated conditions, such as diabetes and Parkinson’s disease. The underlying causes are very different and different cell types would need to be replaced to treat each condition. It is critical that the cell type used as a treatment be appropriate to the specific disease or condition.
Embryonic stem cells may one day be used to generate treatments for a range of human diseases. However, embryonic stem cells themselves cannot directly be used for therapies as they would likely cause tumors and are unlikely to become the cells needed to regenerate a tissue on their own. They would first need to be coaxed to develop into specialized cell types before transplantation. A major warning sign that a clinic may not be credible is when treatments are offered for a wide variety of conditions but rely on a single cell type.
3. Currently, there are very few widely accepted stem cell therapies.
The range of diseases where stem cell treatments have been shown to be beneficial in responsibly conducted clinical trials is still extremely restricted. The best defined and most extensively used is blood stem cell transplantation to treat diseases and conditions of the blood and immune system, or to restore the blood system after treatments for specific cancers. Some bone, skin and corneal diseases or injuries can be treated with grafting of tissue that depends upon stem cells from these organs. These therapies are also generally accepted as safe and effective by the medical community.
4. Just because people say stem cells helped them doesn’t mean they did.
There are three main reasons why a person might feel better that are unrelated to the actual stem cell treatment: the ‘placebo effect’, accompanying treatments, and natural fluctuations of the disease or condition. The intense desire or belief that a treatment will work can cause a person to feel like it has and to even experience positive physical changes, such as improved movement or less pain. This phenomenon is called the placebo effect. Even having a positive conversation with a doctor can cause a person to feel improvement. Likewise, other techniques offered along with stem cell treatment—such as changes to diet, relaxation, physical therapy, medication, etc.—may make a person feel better in a way that is unrelated to the stem cells. Also, the severity of symptoms of many conditions can change over time, resulting in either temporary improvement or decline, which can complicate the interpretation of the effectiveness of treatments. These factors are so widespread that without testing in a controlled clinical study, where a group that receives a treatment is carefully compared against a group that does not receive this treatment, it is very difficult to determine the real effect of any therapy. Be wary of clinics that measure or advertise their results primarily through patient testimonials.
5. A large part of why it takes time to develop new therapies is that science itself is a long and difficult process.
Science, in general, is a long and involved process. Understanding what goes wrong in disease or injury and how to fix it takes time. New ideas have to be tested first in a research laboratory, and many times the new ideas don’t work. Even once the basic science has been established, translating it into an effective medical treatment is a long and difficult process. Something that looks promising in cultured cells may fail as a therapy in an animal model and something that works in an animal model may fail when it is tried on humans. Once therapies are tested in humans, ensuring patient safety becomes a critical issue and this means starting with very few people until the safety and side effects are better understood.
6. To be used in treatments, stem cells will have to be instructed to behave in specific ways.
Bone marrow transplantation is typically successful because we are asking the cells to do exactly what they were designed to do, make more blood. For other conditions, we may want the cells to behave in ways that are different from how they would ordinarily work in the body. One of the greatest barriers to the development of successful stem cell therapies is to get the cells to behave in the desired way. Also, once transplanted inside the body the cells need to integrate and function in concert with the body’s other cells. For example, to treat many neurological conditions the cells we implant will need to grow into specific types of neurons, and to work they will also have to know which other neurons to make connections with and how to make these connections. We are still learning about how to direct stem cells to become the right cell type, to grow only as much as we need them to, and the best ways to transplant them. Discovering how to do all this will take time. Be wary of claims that stem cells will somehow just know where to go and what to do to treat a specific condition.
7. Just because stem cells came from your body doesn’t mean they are safe.
Every medical procedure has risks. While you are unlikely to have an immune response to your own cells, the procedures used to acquire, grow and deliver them are potentially risky. As soon as the cells leave your body they may be subjected to a number of manipulations that could change the characteristics of the cells. If they are grown in culture (a process called expansion), the cells may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types you need. The cells may become contaminated with bacteria, viruses or other pathogens that could cause disease. The procedure to either remove or inject the cells also carries risk, from introducing an infection to damaging the tissue into which they are injected.
8. There is something to lose by trying an unproven treatment.
Some of the conditions that clinics claim are treatable with stem cells are considered incurable by other means. It is easy to understand why people might feel they have nothing to lose from trying something even if it is unproven. However, there are very real risks of developing complications, both immediate and long-term, while the chance of experiencing a benefit is likely very low. In one publicized case, a young boy developed brain tumors as a result of a stem cell treatment. Participating in an unproven treatment may make a person ineligible to participate in upcoming clinical trials (see also number 9). Where cost is high, there may be long-term financial implications for patients, their families and communities. If travel is involved there are additional considerations, not the least of which is being away from family and friends.
9. An experimental treatment offered for sale is not the same as a clinical trial.
The fact that a procedure is experimental does not automatically mean that it is part of a research study or clinical trial. A responsible clinical trial can be characterized by a number of key features. There is preclinical data supporting that the treatment being tested is likely to be safe and effective. Before starting, there is oversight by an independent group such as an Institutional Review Board or medical ethics committee that protect patients’ rights, and in many countries the trial is assessed and approved by a national regulatory agency, such as the European Medicines Agency (EMA) or the U.S. Food and Drug Administration (FDA). The study itself is designed to answer specific questions about a new treatment or a new way of using current treatments, often with a control group to which the group of people receiving the new treatment is compared. Typically, the cost of the new treatment and trial monitoring is defrayed by the company developing the treatment or by local or national government funding. Beware of expensive treatments that have not passed successfully through clinical trials.
Responsibly-conducted clinical trials are critical to the development of new treatments as they allow us to learn whether these treatments are safe and effective. The ISSCR supports participation in responsible clinical trials after careful consideration of the issues highlighted on this site and in discussion with a trusted physician.
10. Stem cell science is constantly moving forward.
Stem cell science is extraordinarily promising. There have been great advances in treating diseases and conditions of the blood system using blood-forming stem cells, and these show us just how powerful stem cell therapies can be. Scientists all over the world are researching ways to harness stem cells and use them to learn more about, to diagnose, and to treat various diseases and conditions. Every day scientists are working on new ways to shape and control different types of stem cells in ways that are bringing us closer to developing new treatments. Many potential treatments are currently being tested in animal models and some have already been brought to clinical trials. In February 2010 the British company ReNeuron announced it had been approved to conduct a Phase I clinical trial of a neural stem cell treatment for stroke. The first embryonic stem cell-based treatment for acute spinal cord injury is currently under review by the U.S. Food and Drug Administration (FDA) and will hopefully move into clinical trials soon. Although it is sometimes hard to see, stem cell science is moving forward. We are tremendously optimistic that stem cell therapies will someday be available to treat a wide range of human diseases and conditions.
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