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In the future, check here or the What's New section for the latest scoop on progress toward a vaccine.
Here is Dr. Dennis Kasper's update as of April 1997:
In the Group B Strep Association's Fall/Winter 1996 Update, I reported on our program to develop and test GBS vaccines. The program, under my direction, is based at the Channing Laboratory (an affiliate of Boston�s Brigham and Women�s Hospital and the Harvard Medical School) and is supported by the National Institutes of Health. Since my last report, we have made additional progress both in the laboratory understanding of how to construct the best possible vaccines and in the clinical testing of vaccines made here at the Channing Laboratory.
As I explained in the last Update, the vaccines consist of the various GBS capsular polysaccharides ("sugar coating") connected to tetanus toxoid. We have determined optimal doses of vaccines for serotypes Ia, Ib, and III. These vaccines are very well tolerated at these and even higher doses, and the antibodies they induce are protective in experimental models of infection. The type II conjugate vaccine is currently being tested at Baylor College of Medicine (Houston), where much of the clinical testing takes place under the direction of Dr. Carol Baker. A new formulation of the type II vaccine has also been prepared and has received clearance from the Food and Drug Administration (FDA) to begin clinical testing in August 1996. Finally, we have collaborated with scientists at the Salk Institute in Swiftwater, PA, to make vaccines under conditions that meet FDA standards for more extensive testing.
According to our preliminary studies, we seem to be on the right track in our attempts to create useful vaccines. We are currently developing strategies to test their effectiveness in a clinical trial.
Dr. Kasper has been on the GBSA National Medical Advisory Board since its inception in 1990. He heads the vaccine research team, the GBS Initiative for the National Institutes of Allergy and Infectious Disease. Dr. Kasper also heads the Channing Laboratory at Harvard Medical School.
Dr. Kasper's previous article in the Winter of 1996 Update...
I am pleased to report that significant progress has been made towards the goals of our GBS vaccine development program.
Investigators at the Channing Laboratory which is affiliated with Brigham and Women�s Hospital and Harvard Medical School, have developed a prototype vaccines for all major serotypes of GBS. These vaccines consist of the GBS capsular polysaccharide (the organism�s "sugar coating") which has been linked by a chemical method to a protein. The protein utilized so far is the tetanus toxoid vaccine. The method for the chemical linkage was developed by our collaborator Dr. Harold J. Jennings of the National Research Council in Canada. The scientific key to our success with these vaccines has been this coupling to protein, which greatly enhances the ability of the capsular polysaccharide to induce protective immunity. In work with experimental models of GBS disease, we have shown that these vaccines are safe when given to animals and induce antibodies in females that cross the placenta to protect newborn animals.
Vaccine prepared at the Channing Laboratory over the past three years has been administered to women in clinical trials conducted by Dr. Carol Baker and her group at the Baylor College of Medicine in Houston and more recently by Dr. Chris Mink at St. Louis University. This work has been done with the support of the National Institute of Allergy and Infectious Diseases a the National Institutes of Health (NIH). Vaccines for serotypes Ia, Ib, and III are currently undergoing clinical testing. Vaccines for serotypes II and V, the remaining major GBS serotypes, are now being prepared for clinical trials. I am pleased to report that the vaccines tested thus far appear to be well tolerated and have caused no serious side effects. Moreover, the vaccines have been highly effective in inducing antibodies that, in conjunction with the immune system, act to kill GBS. These antibodies are of the type that cross the placenta and therefore are expected to be transferred from mother to newborn and to prevent infection in both mother and child.
So far, between 300 and 400 people have received GBS vaccines. What lies ahead will be the optimization of the dose and of the timing and route of the administration. We will need to test these vaccines in a larger number of people and specifically in pregnant women. In order to prepare for such trials, vaccine has been prepared at the Salk Institute in Swiftwater, PA, under an NIAID contract and with help from Dr. Paoletti in the Channing Laboratory. This vaccine has been produced under conditions that are approved by the FDA for more extensive testing. Once the safety and immunogenicity of the vaccines have been adequately assessed, we will plan a test of their effectiveness in preventing GBS disease.
| About the Group B Strep (5 of 5) |
If You're... Pregnant, An At Risk Adult, A Medical Professional. |
