Thursday, August 23, 2018

GABA Starts A Phase-II? Clinical Trial in Honeymooners

This blog has two parts.  The first part describes a phase-I clinical trial in honeymooners which started recently.  The second part summarizes the rest of the GABA (Gamma-Aminobutyric Acid) research done so far in people.  GABA is well known as a neurotransmitter, but it also is generated by pancreatic beta cells and also the immune system, both of which are heavily involved in type-1 diabetes.

GABA is widely available as a "dietary supplement", and you can read a lot more about it here:
There are several mouse studies that show effectiveness against type-1 diabetes.

The Current Clinical Trial

This trial will enroll 95 people with honeymoon type-1 diabetes into three groups as described below.  It is recruiting children aged 4 to 18.  They plan to finish in June 2019.  Primary outcomes are insulin usage and C-peptide generation, while secondary outcomes are levels of diabetes autoantibodies.  All of these will be measured one year after dosing.  People will get two injections of GAD, one month apart.  They will take GABA pills twice a day.  I think the pills will be for a year, but I might be wrong about that.

The three patient groups are:
    Some people will get two different placebos, and be a control group.
    Some will get GABA and a placebo for GAD.
    Others will get both GABA and GAD.

GAD is developed by Diamyd corporation, and has been tested for at least 10 years.  I've blogged on it in the post many times:
It has a long history of safety, but also of not being effective.  So I don't hold out much hope for the GAD alone being effective.  But that doesn't really matter, because GAD alone is not being tested.  Since two different arms will get GABA, if that is effective, it will be obvious.  If the GAD + GABA arm is more successful than the GABA only arm, that would breathe new life into GAD research.  In animals, GAD is part of the biochemical mechanism which creates GABA, so the two are related.

This trial is marked in the FDA registry as still recruiting at one site, however the press release from Diamyd says it is already fully enrolled:
    Children's [Hospital] of Alabama, Birmingham, Alabama, United States, 35233
    Contact: Sharon D. May, BSN    205-638-5031 
    Contact: Heather Choat, MD    205-638-9107 
    Web page:

The researchers considered this a phase-I trial, but because of the size and the previous GABA clinical trials, I'm treating it as a phase-II? trial, meaning a trial big enough to be phase-II, but without results from a previous phase-I trial done on people with type-1 diabetes.

Press Release:
USA Clinical Trial Registry:
WHO Clincal Trial Registry:

This research is funded by JDRF and the companies that manufacture GAD (Diamyd / Johnson and Johnson) and GABA (NOW foods).

Preview of Coming Attractions: Diamyd, the company that researched GAD is now also working on a GABA based drug called Remygen.  A research group in Sweden is planning to start a trial of this drug in people with established type-1 diabetes in Sept 2018. I'll blog on these trials when it starts.  Clinical Trial Record:

A Little History

Back in 2012 Penny Jester, a researcher at the University of Alabama at Birmingham, tried to start a clinical trial in GABA.  However, the FDA did not approve her IND (Investigational New Drug) application, and so the trial was never started.  You can see the registration here:

In 2013 Zhaoyun Zhang and fellow researchers at Huashan hospital in Shanghai, China ran a small study (confirming safety) on GABA in healthy people, reported here:
and  registered here:

Then in 2013 the same group started a 60 person phase-II? study of GABA on people with honeymoon type-1 diabetes, but I have not been able to find published results.

You can read Dr. Zhang's rational for testing GABA in this paper:

More Reading

Because both GABA and GAD have long histories as potential cures for type-1 diabetes, there is lots of previous research to read, if you want: (mice)

Joshua Levy
publicjoshualevy at gmail dot com
All the views expressed here are those of Joshua Levy, and nothing here is official JDRF, JDCA, or Bigfoot Biomedical news, views, policies or opinions. In my day job, I work in software for Bigfoot Biomedical. My daughter has type-1 diabetes and participates in clinical trials, which might be discussed here. My blog contains a more complete non-conflict of interest statement. Thanks to everyone who helps with the blog.