Happy Saturday! Even though I am pretty convinced I will not be invited to be a part of this study – my vision is not bad enough – I did get the patient informed consent packet and I can browse through that with you. I want to look at it and see what’s happening.
The formal title is very long. What it says is it is a two-part study. One part is a phase one, safety and tolerability study, and the second part is a phase two, proof of concept study. Both studies are being run in several different locations (multicentered), and they are unmasked. Unmasked means that everyone knows what he or she is being given. For example, if they were testing to see if aspirin is better than Tylenol, all the participants would know which drug they had been given.
The independent variable in each is the size of the dose of stem cells. The independent variable is what the researchers are manipulating. The protocol is dose escalation meaning there are different groups of subjects, and they will be receiving increasingly larger numbers of stem cells, one group to the next.
And I am still working through the title, guys!
Two more terms and the title is done: parallel groups and randomized groups. In parallel design, research subjects are assigned to different treatment groups – in this case, size of dose – so that the effects of the different treatments can be compared. Randomized assignment is done pretty much by chance and is hoped to yield groups that have no real differences between them. It is hoped that any differences found after the research is run will be because of differences in treatment and not due to some other factors.
Ok. THAT was the title! Moving on.
The study uses human embryonic-stem-cell-derived retinal pigment epithelial cells (RPEs). Remember these cells come from blastocysts. Blastocysts are balls of between 200 and 300 cells and are about 0.1 to 0.2 mm in diameter according to Wikipedia. A sheet of paper is 0.1 mm thick to give you a point of reference. Blastocysts, at 5 to 6 days after fertilization, have not yet implanted in the uterus.
That last paragraph is information someone might need to make an informed decision on whether or not they want a treatment with human embryonic stem cells. If you think life begins at conception, this might not be a treatment for you.
If you decided to participate in a stem cell study, at least one using embryonic stem cells, you will need immunosuppressants. Getting these cells is actually a transplant. It is related to getting a new kidney (related but NOT the same). Even though the eye has immune privilege, the study will do 13 weeks of immunosuppressants. I imagine it is the immune privilege of the eye that limits this to 13 weeks rather than a lifetime of immunosuppressants as happens with major organ transplants.
Immune privilege? Oh yeah. According to the Wiki people, immune privilege basically means the organ can tolerate the introduction of antigens without eliciting the inflammation response, part of the body’s defenses; remember? The big immune-privileged organ is the brain. Since the eyes are actually just extensions of your brain, they have great immune privilege also.
I am officially way over my 500 words for this so I am quitting now. Back to it later!
Written July 7th, 2018