November 22, 2011
Last week I attended, with Ryan, a great research session sponsored by the Maryland chapter of the ADA where we learned about the advances in research and a cure for type 1 diabetes. I learned a lot and then did some more research after on the notes that Ryan and I took – mostly because he is going to do a science fair project on diabetes and research. Here is the education we have learned about the possible cures and better management that is HOPEFULLY going to be available within Allison’s lifetime. (Some of this language is technical – I am not a medical professional so kept them as I found them because I don’t really know how to explain in laymen’s terms yet!)
To "cure" type 1 diabetes, a therapy would either have to replace the beta cells that have been destroyed and prevent further beta cell loss, or closely mimic the normal insulin producing function of beta cells in a way that does not require constant management. Another way to think of a "cure" is that it would either prevent diabetes from ever happening, halt it in its very early stages, replace lost beta cells, or make up for lost beta cell function without placing additional burdens on the person with diabetes.
Four approaches known as immune therapeutics, islet transplantation, regeneration of beta cells, and the artificial pancreas could potentially achieve these goals. Here are those potentials:
1. Immune Therapeutics
The goal of immune therapeutics is to modify or modulate the immune system in a way that prevents the destruction of beta cells. This type of approach address diabetes at a cellular level, attempting to "cure" the root cause of the disease: the immune system's components are not functioning the way they should. Several approaches to immune therapy are being developed. These include diabetes vaccines, as well as drugs that target specific components on the immune system response in an attempt to shut down ongoing beta cell destruction, and reinitiate the normal mechanisms that prevent the immune system from destroying healthy parts of the body.
Unfortunately, recent developments in immune therapy have not been encouraging as several recent trials have failed to show adequate efficacy, both for vaccines and for immune modulating drugs. Nevertheless, research in this field continues and several clinical trials are still ongoing.
2. Islet Transplantation
Islets, found in the pancreas, contain a number of different cells, which produce hormones involved in controlling blood glucose levels, most notably beta cells. Islet transplantation replenishes lost beta cells through an infusion of islets from another source, which using today’s technology involves using islets from a deceased donor. Deceased donor islets are not available in large numbers, substantially restricting the number of transplants that can be performed each year.
Islet transplantation is a potential cure in that the transplanted "new" islets will work in place of destroyed ones. In fact, estimates suggest that over two-thirds of people who receive islet transplantations no longer require insulin injections one-year after the procedure. The procedure works well and lowers insulin dose requirements or removes the need for injectable insulin entirely. Unfortunately, this treatment is not long lasting, and five years after transplant, only 10 percent of people are able to remain independent of injectable insulin.
The biggest risk of islet transplantation is the accompanying immune suppressive therapy, which is necessary to prevent rejection of the transplanted islets just as it is necessary after transplantation of any other organ from an unrelated donor. Immune suppressive drugs have many side effects, including damage to the kidneys, and an increased risk of infection.
Many companies and academic researchers are trying to develop new methods to generate beta cells for transplant (in order to circumvent the limitations of small numbers of deceased donor organs).
3. Beta Cell Regeneration and Survival Therapies
In light of the challenges of islet transplantation, the discovery of ways to stimulate new beta cells to grow within the pancreas of people with diabetes, and protect their health and survival would represent a major leap forward.
If successfully developed, drugs that stimulated beta cell regeneration could be used for any person with type 1 diabetes as a means to restore beta cells and regain independence from insulin therapy. They may also halt the progression of type 1 diabetes in people in the early stages of disease, by (ideally) stimulating an increase in beta cell numbers beyond that necessary to compensate for loss due to immune destruction.
Animal research has provided scientists with useful targets for development of regeneration therapies. In addition, considerable attention has been turned to the use of incretins (a group of drugs that includes two classes approved for the treatment of type 2 diabetes). Basic research in animals indicates that incretins can help beta cells survive longer and regenerate more readily, giving them the potential to ameliorate type 1 diabetes.
4. The Artificial Pancreas
The artificial pancreas (AP), though not a cure for diabetes in the traditional sense, is an extraordinarily promising technology. The AP is an automated device that tries to reproduce the function of a normal pancreas by delivering the right amount of insulin (and maybe other hormones) to maintain normal glucose control. In the AP, a continuous glucose monitor (CGM), and insulin pump, and a control algorithm work together to do the pancreas's job. A truly "closed loop" AP would require no intervention from the patient, while an "open loop" would require some intervention. We see the AP as a bridge to the cure for diabetes but, using technology similar to that currently developed, not a true cure by itself.
One of the biggest problems facing the development and use of an AP is that varied sleep patterns, exercise, diet, and stress can all influence blood glucose, and can be very difficult for current technology to handle, often leading to under or over pumping of insulin. Increasingly sophisticated algorithms, more accurate CGMs, and faster insulins are all being developed to address these problems. In addition to technological hurdles, regulatory caution has slowed the implementation of some new technologies in the U.S., and may prove to be a significant stumbling block in the path to developing a workable AP.
Although the technical and regulatory issues have yet to be solved, an AP system operating in even a very broad target range while presenting a low risk of hypoglycemia could yield enormous A1c benefits.
While movement is slower than anyone would like to see, the progress toward finding a cure for type 1 diabetes is exciting and ultimately HOPEFUL. Though development may take many years, several may one day be an option for curing those like Allison with type 1 diabetes. Keeping your eye towards legislation and helping funding are key to progressing these things and ensuring those that will benefit from these options are given them in a timely manner.
Until there is cure,
Jennifer
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