Wednesday, November 17, 2010
Risks of Human Embryonic Stem Cell Clinical Trials for Spinal Cord Injury
I am especially concerned for the protection of the patients who enroll in this trial. The reason being is that this trial holds high risks to the patient. Most of the public is not aware of the risks and limitations of embryonic stem cell research.
Geron has designed their initial safety trial to only enroll patients with recent non-severed spinal chord injuries. These injuries are designated as crushing or contusion spinal chord injuries. Geron will be monitoring the outcome of the trial by if a patient can gain some improvement such as the ability to “wiggle their toes” days or months subsequent to the treatment.
Geron didn’t pick this group of patients without considerable forethought to promote their product. In fact, this population of patients is the most likely spinal chord injury population that would make Geron’s drug look good, when indeed it may not be good at all. The reason being is that since the patient’s spinal chords have not been severed, these patients have a marked probability of recovering from these injuries to various degrees without embryonic stem cell treatment.
Consequently, a “wiggle toe” outcome in Geron’s trial will not project any conclusive data toward determining the efficacy of Geron’s embryonic stem cell drug. (Although I can reasonably predict and would actually gamble on the fact, that when the first treated patient wiggles his toes, the scientific propaganda machine will undoubtedly tout it as an embryonic stem cell miracle cure to the unsuspecting population. I can see a picture of the toes wiggling in the newspapers already.)
And although the sight of someone wiggling their toes after incurring such a horrific injury to their spinal chord brings joyous emotions to anyone with an ounce of empathy for their suffering, the patient receiving the embryonic stem cell treatment is not home free. They took a risk when entering this trial. A big risk.
One of the major risks involves a cellular process called differentiation. Differentiation is a complex process within embryogenesis that makes an embryonic stem cell “morph” into individual adult cells, all with different roles and purposes in an amazingly well orchestrated fashion. As scientists, we have limited understanding of this process.
So when a scientist attempts to “differentiate” an embryonic stem cell in a tissue culture dish instead, the process is not perfect. And what may "look" like a differentiated neuron to our limited understanding as scientists…may actually not be a neuron. In fact, it may be a “wolf in sheep’s clothing”. And when implanted into a patient, it could cause devastating results.
The RISK to the patient is incredibly high in undergoing this embryonic stem cell treatment. And the Geron trial is no exception.
Even if the treated patient “wiggles his toes” after receiving the embryonic stem cell treatment, he may very well succumb to a teratoma or auto immune disorder years later. These risks are real and they are well documented in animal studies in the scientific literature regarding embryonic stem cell therapies.
I do hope that these spinal chord injury patients who will be in the unfortunate position to consider entering into Geron’s human embryonic stem cell clinical trial will receive thorough counseling prior to giving consent. One can only imagine that the patient considering this option is DESPERATE at the time of injury since he is paralyzed, albeit perhaps only temporarily.
I would highly advice those families who have a loved one who is considering entering this trial to seek both objective and independent scientific and legal counsel before signing any consent form. Make sure you understand every sentence in the consent contract…even the small print. Make sure that the experts you choose to counsel with have no conflicts of interest with the Geron trial, which unfortunately is sometimes hard to determine.
Keep in mind that this is a SAFETY trial and not an efficacy trial. That is, it has been designed to look at the SAFETY of the product and not for a cure.
Geron’s human embryonic stem cell is a dangerous trial, the safety outcome of which is not only measured within the initial months but decades later.
If you have any questions, contact me at firstname.lastname@example.org.