Tuesday, August 31, 2010

Possible Cures for Type-1 in the News (late-Aug)

GCSF (Neulasta/Pegfilgrastim) Starts a Phase-I Clinical Trial
This is straight forward trial where GCSF is given to people in the honeymoon phase of type-1 diabetes.  It is interesting for many of the same reasons that the ATG+GCSF trial is interesting (see older post on ATG+GCSF).  Both of these trials are being done at the University of Florida, and Dr. Michael J. Haller is involved in both.

Clinical Trial Record: http://www.clinicaltrials.gov/ct2/show/NCT00662519

There is a second GCSF clinical trial being done at the University of Padova (Padova, Padua, Italy), but it is not aimed directly a curing type-1 diabetes.  Although I don't understand it fully, it appears to be more basic research into GCSF effects on people with type-1 diabetes.  Clinical trial record is here: http://www.clinicaltrials.gov/ct2/show/NCT01102699

A Little Discussion: Why a GCSF only Trial?
One obvious question that came to mind when I saw this GCSF only clinical trial, done at the same place and time, and by the same researcher as doing the ATG and GCSF trial, was: why do both?  I mean, if GCSF works, then certainly ATG and GCSF will work, and clinical trials are a lot of work and expense.

The answer to this question (for me) has to do with with three separate, but related goals:
  1. We want to cure type-1 diabetes. (Cure Product Development.)
  2. We want to learn how drugs effect type-1 diabetes, so we can find a cure.  (Basic research.)
  3. We want the FDA to approve clinical trials which lead to points 1 and 2.
If you only look at point 1, then a GCSF-only trial (when a GCSF+ATG trial is also ongoing) might sound like a waste of time.  As a parent of a child with type-1 diabetes, I often focus only on point 1.  However, product development flows out of basic research, so points 2 and 3 are also important.  It may turn out that studying GCSF alone will help create a cure in the future, or that the FDA might require more knowledge of GCSF alone before it will approve some future clinical trial, which leads to finding a cure.

In the past I have blogged about not understanding how  Sitagliptin alone, or Sitagliptin and Lansoprozole combined, could cure type-1 diabetes.  However, it may be that these clinical trials will be valuable, because of points 2 or 3 above.  They might be the basic research or FDA required background that eventually leads to a cure, even if they are not the cure themselves.

LCT Announces Completion/Extension of their Phase-II Trial
LCT has announced these things in August:
  1. Their phase-II trial has been extended with 4 new patients who will get dose 20k u/kg dose.  The phase-II study now includes 4 who got 10k u/kg, 4 who got 15k u/kg and these 4.  This is a 50% expansion of their study, at 33% higher dose.
  2. The first four patients have seen a benefit of fewer (or elimination) of low BG episodes.  Only two such events, compared to nineteen, so almost a 90% drop.
  3. They plan "commercial launch" in 2013, and "global reach though partnership".  They seem to be assuming that the operation will cost about $150k (I think this is US$, but not sure.)
  4. They have also laid out the following time line for getting to commercial availability, which is the most detailed that I've seen:
  • 2011: Continue phase-II trials, get approval for phase-III trial (They use the term "pivotal".)
  • 2012: Complete phase-III, report on results.
  • 2013: "Approval and revenue"
That's their plan, and I hope they make it.  I see the following issues for them to overcome.  First, they need to have a cure.  Right now, the longest they have had anyone insulin-free is 32 weeks, and only two people (out of twelve) have been insulin free for any number of weeks.    Obviously they need to improve both of these numbers.  (Although, if you view them as a treatment to help brittle diabetics, then their results might be good enough already - depending on how long they last - but that wouldn't be a cure.) Second, they need to treat enough people to get their approvals.  Right now, they have treated a total of 16, with 4 more on the way.  That is far fewer patients than any other phase-II trial that I know of.  A more common count is 20-30 in the phase-I trial, 80-120 in phase-II, and 300 in a phase-III "pivotal" trial, and then a second phase-III trial for confirmation.  (Basically all the drugs in phase-III trials have followed that path.)  LCT is running at about 1/3 the size in their phase-I trial, and 1/10 the size in their phase-II.

Press release: http://www.blogger.com/post-edit.g?blogID=5472921328078253036&postID=548554300707664816
Corporate Overview: http://www.lct.com.au/downloads/cms_latest_news/2010-08-26-Presentation%20August%2010.pdf
This corporate presentation contains a lot of information on where they are, what they plan to do in the future, and how they plan to make money.  It is targeted at investors, after all.

NovImmune has started a phase-II for NI-0401
This company is very hard for me to follow, because they don't issue many press releases, don't have the clinical trial records, that most other researchers have, and it is just generally hard to find information on them.  The  are a small, relatively new company and their lead product (the one farthest along is the drug development process) is NI-0401 which is and anti-CD3 drug, generally similar to the Teplizumab and Otelixizumab

Their recent corporate literature makes it clear that NI-0401 has started a phase-II clinical trial for type-1 diabetes.  Unfortunately, I have not been able to find clinical trial records for either the phase-I or phase-II trials, so I have no ideas how many patients are involved, if they are honeymoon or not, or any other of the most basic information about the study.  Even worse, I can not find any published results for the phase-I study in type-1 diabetics.  (I did find results for their phase-I trial on Crohn's disease, but not tyoe-1.)

Corp presentation: http://www.swissequitybiotechday.ch/media/biotechday/downloads/novimmune.pdf

AP News: Faster Insulin
Below is a link to a JDRF press release on their project to created faster acting insulin (mostly to help their Artificial Pancreas project):
I normally would not cover it, because it doesn't talk much about results or progress, however I did want to mention it because it is much broader and contains more context than your usual press release.

Most press releases just cover one piece of news for one line of research, but this press release gives a lot more useful context to the search for faster acting insulin.  Basically, it starts out with a goal.  The goal is to get faster acting insulin, mostly because it will make creating an artificial pancreas easier, and make the resulting pancreas better.  (Obviously,  it will also help everyone who uses insulin with meals, which is basically all type-1s.)  The simplest way to speed up insulin (and the way done in the past) is to create a new form of insuilin which is faster than the currently available forms.  And JDRF is funding Dr. Buckingham at Stanford to test one of those.  Another way is to find a faster pathway into the body.  So JDRF is funding Dr. Zisser testing of AFREZZA, which is inhaled insulin; the hope is that inhaled equals faster.  A third idea is to use microneedles to deliver insulin faster (JDRF is working with BD on this one).  A fourth is a port-system which puts insulin from a standard pump directly into a person's liver.  Since insulin mostly effects the liver, this could speed up the effectiveness of pumped insulin.  (JDRF is working with Roche on this.)  Finally, there is a post-pump insulin warmer which might also speed up insulin effectiveness.  (JDRF is funding Dr. Tamborlane of Yale to test this for InsuPatch.)

My Opinions.....
The whole point of research is that you don't know which projects are going to pan out and which are not.  This press release shows how JDRF is trying many different possible paths to faster insulin.  Some of those paths seem like good ideas to me.  Others seem very inventive, if a little strange.  Others don't strike me as unlikely to succeed.  I'm sure other people looking at the same list will expect different research to fail and succeed than I do.  That is why JDRF is funding all of them.  No one knows which will pan out.  I believe that this whole project is part of JDRF's "glucose control" research area, and that whole section includes about 6% of their funding.  So even though it sounds like a lot of different research projects in different areas (and it is!), all together it is only a few percentages of JDRF's total investment.   It doesn't even begin to touch the 33%+ aimed at immune therapies or the 40% aimed a regrowing beta cells.

JDRF Page on Spending: http://www.jdrf.org/index.cfm?fuseaction=home.viewPage&page_id=0B36CA86-9128-4C49-B7D8F55955507931

Joshua Levy
All the views expressed here are those of Joshua Levy, and nothing here is official JDRF or JDCA news, views, policies or opinions. 
Blog: http://cureresearch4type1diabetes.blogspot.com
Web: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials

Monday, August 23, 2010

Possible Cures for Type-1 in the News (mid-Aug)

Sitagliptin and Lansoprazole Preparing for a Phase-II Clinical Trial
This trial is giving two drugs (both of which are already in use) to people with type-1 diabetes in their honeymoon phase.  The hope is that it will preserve some beta cell function.  This study is not yet recruiting patients.  They hope to recruit 54 patients and finish in April 2014. Sitagliptin is the generic name for Januvia, and Lansoprozole is the generic name for Prevacid.

A Little Discussion: I still don't understand why this is supposed to preserve beta cells.
When I blogged about the Sitagliptin only clinical trial, I said that I didn't understand why it might help type-1 diabetics; and I still don't.  With this trial, I don't understand why adding a antacid like Lansoprozole would help type-1 diabetics, either.  On the other hand, Januvia is available now for type-2 diabetes with a prescription, and Prevacid is available "over the counter" and as a generic.  So if this pans out, you will be able to get this as an "off label" use without waiting for further FDA approvals.

For me, a far more interesting trial, which I have blogged about before, is being run by the NIH, and which uses Diamyd plus Sitagliptin and Lansoprozole.  That one I understand: Diamyd stops the autoimmune attack by retraining it, and the other two drugs reverse beta cell damage or develop new beta cells.  You can read about that study here:
and I think they have upped the enrollment to 7 since I wrote that blog entry.  On the other hand, if this Sitagliptin and Lansoprozole only study lays a scientific foundation for more studies where they pair it with something to stop the autoimmune attack, that would be valuable.

News article: http://www.argusleader.com/article/20100811/NEWS/8110318/1001
Clinical Trial Record: http://www.clinicaltrials.gov/ct2/show/NCT01155284

Other Phase-II trial of Sitagliptin: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials#SitagliptinbyGarg
Blogging on Sitagliptin: http://cureresearch4type1diabetes.blogspot.com/search/label/Sitagliptin
Wikipedia for Sitagliptin: http://en.wikipedia.org/wiki/Sitagliptin
Wikipedia for Lansoprazole: http://en.wikipedia.org/wiki/Lansoprazole

Delay in Trucco's Phase-I Trial
Trucco's clinical trial is one of the first ones that I ever followed in my "status" web page.  That was years before I started my blog.  I've never blogged on it, because there has never been news.  Basically, they remove dentric cells, which are part of the immune system, treat those cells, and then put them back in the patient (the same patient where they came from).  This trial only enrolls people who have had diabetes for more than five years, so honeymooners are excluded.  It is a safety only study: they are not measuring any BG, A1C, insuline usage or C-peptide numbers.  If it turns out safe, then they plan to start a honeymooner only study to see if it improves any of those things. 

Now, finally, there is news.  In June 2010, Trucco's group updated their clinical trials record as follows:

Estimated Enrollment: 15
Study Start Date: March 2007
Estimated Study Completion Date: June 2011 (previously had been mid-2010)
Estimated Primary Completion Date: December 2010 (previously had been mid-2009) 
So this is basically a one year slip.

Web status page: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials#TruccoatChildren%E2%80%99sHospitalofPittsburgh 
Year old newspaper article: http://durangoherald.com/sections/Features/Health/2009/08/24/Experiment_seeks_way_to_head_off_Type_1_diabetes_found_in_children/
Scientific Overview: http://www.mcgowan.pitt.edu/news/images/Trucco_PediatricDiabetes_2008.pdf
(Includes a nice diagram on page 8, even if the rest is highly technical.)

One Possible Cure, but not yet in Clinical Trials.
Some researchers in India are working with a "release as needed" injected insulin.  This is broadly similar to SmartInsulin.  A single injection of this new insulin, called Supramolecular Insulin Assembly II (SIA-II) resulted in good blood glucose levels (which they call "physiologic glucose levels") for over 100 days in animals.  I'm very much looking forward to what this does in people.  But remember: drugs generally take 10+ years to go through human trials, and less than half of the drugs successful in animals ever go on to human trials.  (Since this is an Insulin it might be slightly faster than 10 years, but not much.)

Abstract: http://www.pnas.org/content/107/30/13246.abstract
News report: http://www.dnaindia.com/india/report_india-develops-single-shot-insulin-for-diabetics_1409481

Another benefit of this drug, is that it puts pressure on the SmartInsulin developers.  In turn the SmartInsulin developers put pressure on the SIA-II developers.  I'm a firm believer that competition pushes both groups of developers to move faster, so I'm all for it.  It sounds to me like both SmartInsulin and SIA-II are close to starting human trials, but SmartInsulin is closer.

Discussion: What is a Cure?  Is this a Cure?
This drug (and also Smart Insulin) can start off an interesting parlor conversation about what is a cure?  Are treatments like SmartInsulin or SIA-II cures?   Obviously, each of us must make up their own mind about what is and is not a cure.  But in my mind, a treatment that required one injection every 3 months, and no blood glucose checks, no dietary limitations (no counting carbs), with no long term side effects and a normal life expectancy.  Personally, I would call that a cure, even though it requires an injection every 3 months, and even though you would have type-1 "on the inside".  It would be a functional cure.  Your opinion may differ.

News from Cerco Medical
I don't really cover Cerco Medical, because they have not yet started human trials for their "islet sheet", which is an encapsulated beta cell cure generally similar to LCT's  Diabcell.  However I know people are interested in it, and this is the most specific news I've heard about when they are hoping to start a clinical trial:
His [Scott R. King, president of Cerco Medical] company is planning to begin human testing in 2012 or 2013.  
This comes from a newspaper article, which is mostly about Artificial Pancreas work in Oregon:  http://www.oregonlive.com/health/index.ssf/2010/08/putting_blood-sugar_control_on.html

Joshua Levy
All the views expressed here are those of Joshua Levy, and nothing here is official JDRF or JDCA news, views, policies or opinions. 
Blog: http://cureresearch4type1diabetes.blogspot.com
Web: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials

Thursday, August 19, 2010

Eight New Stem Cell Clinical Trials For Type-1 Diabetes

I hate putting out half-digested information, but I'm convinced that I will never have time to fully digest all of these studies, so I'm putting out what I have, on the basis that something is better than nothing.

This is a list of eight studies, which are pretty similar.  They all involve using stem cells to treat or cure type-1 diabetes.  Some of these studies use adult stem cells, others embryonic, and others cord, although I think the most common is the patient's own bone marrow stem cells.

I consider stem cells to be one possible way to regenerate beta cells.  My opinion of beta cell regeneration in general, is that it is not going to cure type-1 diabetes by itself (because the autoimmune attack will kill the new beta cells same as the old ones) but that it might be an important part of the cure.  It's importance depends on how fast beta cells regrow after the autoimmune attack is stopped.  If they grow back quickly, then no form of beta regeneration will be needed, but if they grow back slowly or not at all, then some form of beta regeneration will be needed.  Stem cells are one form of beta cell regeneration, but there are others.  Exsulin and human growth hormone have been tested in people, and CureDM's drug in animals, and there are many more.

The good news here, is that there is a lot going on with stem cells, so if we do end up needing new beta cells to cure type-1 diabetes, here are 8 or more reasons why we are likely to have them.  And that is not even counting all the non-stem cell technologies out there.  But (in my opinion) the "gating factor" (what we in the software industry call the "critical path") to curing type-1 on this path is stopping the autoimmune response, not regenerating the beta cells.

As you read these, you will notice that some of them have end dates in the past, but are still active today.  Others have start dates in the past, but have not actually started recruiting patients.  These are signs that the researchers have not updated the clinical trial records, and need to.  This is quite common.  "Primary Completion" is when they finish collecting the data from the patients.

Uppsala University Hospital Stem Cell phase-I Trial
Treatment of Patients With Newly Onset of Type 1 Diabetes With Mesenchymal Stem Cells

Estimated Enrollment: 20
Study Start Date: March 2010
Estimated Study Completion Date: January 2012
Estimated Primary Completion Date: January 2011
Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT01068951

Armed Police General Hospital
Stem Cell Therapy for Type 1 Diabetes Mellitus
Cellonis Biotechnology Co. Ltd.
Estimated Enrollment: 24
Study Start Date: August 2010
Estimated Study Completion Date: December 2011
Estimated Primary Completion Date: August 2011

Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT01143168

Hospital Universitario Dr. Jose E. Gonzalez
Hematopoietic Stem Cell Transplantation in Type 1 Diabetes Mellitus
Estimated Enrollment: 15
Study Start Date: May 2010
Estimated Study Completion Date: March 2011
Estimated Primary Completion Date: December 2010
Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT01143168

Shanghai Jiao Tong University School of Medicine 
Autologous Hematopoietic Stem Cell Transplantation for Early Onset Type 1 Diabetes
Estimated Enrollment: 30
Study Start Date: February 2008
Estimated Study Completion Date: February 2013
Estimated Primary Completion Date: January 2013
Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT00807651

Veterens Memorial Medical Centre
Safety and Efficacy of Autologous Adipose-Derived Stem Cell Transplantation in Patients With Type 1 Diabetes
Adistem Ltd
Estimated Enrollment: 30
Study Start Date: November 2007
Estimated Study Completion Date: December 2009
Estimated Primary Completion Date: November 2009

Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT00703599

Shandong University
Autologous Bone Marrow Mononuclear Cells Transplantation in Treating Diabetes Patients

Estimated Enrollment: 200
Study Start Date: March 2006
Estimated Study Completion Date: March 2014
Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT00465478

Technische Universität München
Cord Blood Infusion for Type 1 Diabetes Mellitus (T1DM)
23 patients, but no start or end dates provided
Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT00989547

University of Moron
Safety and Efficacy of Arterial Delivery of Autologous Bone Marrow Cells in the Treatment of Insulin-Dependent Diabetes
Stematix, Inc
Estimated Enrollment: 34
Study Start Date: October 2009
Estimated Study Completion Date: October 2014
Estimated Primary Completion Date: October 2011
Clinical Trial: http://www.clinicaltrials.gov/ct2/show/NCT00971503

Joshua Levy
All the views expressed here are those of Joshua Levy, and nothing here is official JDRF or JDCA news, views, policies or opinions.
Blog: http://cureresearch4type1diabetes.blogspot.com
Web: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials

Saturday, August 14, 2010

ATG + GCSF Starts a Phase-I Clinical Trial

ATG + GCSF Starts a Phase-I Clinical Trial
This is a very interesting study, which is why I'm giving it, it's own blog posting.  The official title of this study says it all, optimistically: "Reversing Type 1 Diabetes After it is Established".  It builds on three separate lines of research: Burt's ATG/GCSF/cyclophosphamide trial, a separate line of ATG-only trials, and NOD mice trials on ATG and GCSF (all discussed more below).

The basic idea behind this research is that ATG modulates the body's immune system, while GCSG  causes the body to generate more t-cells directly from it's own bone marrow.

ATG is a mixture of different antibodies that target T cells, including the anti-CD3 antibody.  The hope is that this multi-faceted approach will be even more successful and have a longer lasting effect than with anti-CD3 alone, and may treat diabetes by several mechanisms. First, it lowers the number of T cells, so there are fewer to attack the beta cells. It also seems to alter the T cells remaining behind, rendering them less likely to be destructive. Following this depletion, the T cells that grow back in the following weeks may be reset and have a healthier balance (meaning that a special type of T cells, called regulatory T cells, will help keep the destructive T cells in check).

GCSG  is essentially a growth factor that helps the body repopulate the cells after ATG depletes them.  So, if ATG fixes the immune system by getting rid of the destructive cells, and the GCSG can cause the body to generate more t-cells afterwords, and presumably a healthier balance of these cells, then the two together could stop the autoimmune defect that causes type-1 diabetes.  (Regrowing new beta cells might still be required for some people.)  And, this process has already been used successfully to cure type-1 diabetes in mice, so that is always a good first step.

But the really positive thing about this research is it's relationship to previous research by Burt.  You can read my previous blog entries about Burt's research at the URL below, but the quick summary is this: Burt has -- by far -- the best results in people of any researcher.  That study used a combination of 3 drugs, ATG, GCSF, and cyclophosphamide.  Some patients went into remission (no need for injected insulin) for a period of years, others for months, and all of these people used much less insulin after the trial.  Only two patients in the study did not go insulin free for at least a few months.  This research also has a serious weakness, which is safety.  Although none of the people in Burt's had serious side effects, the process involves "rebooting" the immune system.  So while this is happening, the patients are in an isolation ward, because their immune system is highly compromised.  Also, there were "hints of toxicity" seen in the trial: a few people had unusual infections, and some of the males had reduced sperm counts afterward.  Burt's research was in honeymoon diabetics, only.

A second line of research that has been going for years uses ATG alone to try to preserve beta cell function in honeymoon type-1 diabetics.  This research has already completed a phase-I study, and a phase-II study is underway right now.  The phase-II study is called START and they hope to finish recruiting patients in 4-6 months.  ATG alone is very good in curing mice, but in combination with GCSF the success rate is nearly 90% for the mice, and hopefully that will translate to people.

Oversimplified a little: Burt's research involves using three drugs (ATG, GCSF, and cyclophosphamide), and reinjecting the patient's own precursor bone marrow cells (previously removed). Dosing with just ATG and GCSF can be viewed as a "kinder, gentler" Burt. Especially since the cyclophosphamide is the one that really hammers the immune system and requires the isolation ward. 

In the past, I've been asked who was following up Burt's research, and this is a pretty direct follow up. Most phase-I trials are aimed at minimum effect and maximum safety, so minimal doses are used.  The follow on research usually involves more drugs.  However, in this case the effectiveness is high, while the safety is the issue.  So the follow on research involves less drugs.  In this case it involves removing the most toxic drug from the treatment.

They are enrolling 25 people who have had type-1 diabetes for more than 4 months, but less than 2 years.  Planned completion date is April 2013.  They are recruiting at the University of Florida, which is in Gainsville.  UCSF (San Francisco, California, USA) and also the Davis Center (Denver, Colorado, USA) will be participating in this study, but they are not listed in the clinical trial record.  The coordination is through University of Florida by Dr. Michael Haller (who is running several other clinical trials aimed at type-1 as well).  The email contact is listed as hallemj@peds.ufl.edu, so I would start there if you are interested.

Previous blogging on Burt's research:  http://cureresearch4type1diabetes.blogspot.com/search/label/Burt
Previous blogging on ATG: http://cureresearch4type1diabetes.blogspot.com/search/label/ATG

Description of study: http://diabetes.ufl.edu/research/clinical-trials-and-studies/established-type-1-diabetes/atggcsf-clinical-trial/
Clinical Trial Record: http://www.clinicaltrials.gov/ct2/show/NCT01106157
Abstract of animal study: http://www.ncbi.nlm.nih.gov/pubmed/19628781?dopt=Abstract
Wikipedia for GCSF: http://en.wikipedia.org/wiki/Neulasta
Wikipedia for ATG: http://en.wikipedia.org/wiki/Anti-thymocyte_globulin

I'd like to thank Dr. Steve Gitelman (who is a Principal Investigator in the ATG START study) for his thoughts on this research.  All mistakes here are my own.

Joshua Levy
All the views expressed here are those of Joshua Levy, and nothing here is official JDRF or JDCA news, views, policies or opinions. 
Blog: http://cureresearch4type1diabetes.blogspot.com
Web: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials

Monday, August 9, 2010

Cinnamon and Vitamin-D

I don't usually blog on treatments for type-1 diabetes, but these two come up every now and then, and so I looked up the clinical trials for Cinnamon and also for Vitamin-D:

Studies of Cinnamon

Every now and then I hear about cinnamon helping diabetics, so I did a search for studies done on humans that gave cinnamon to people with type-1 diabetes.  There was only one.  You can read the whole paper here: http://care.diabetesjournals.org/content/30/4/813.full.pdf+html
The clinical trial record is here: http://www.clinicaltrials.gov/ct2/show/NCT00371800
Here is the important bits from the abstract (numbers removed):
RESULTS— There were no significant differences in final A1C, change in A1C, total daily insulin intake, or number of hypoglycemic episodes between the cinnamon and placebo arms.
CONCLUSIONS— Cinnamon is not effective for improving glycemic control in adolescents with type 1 diabetes.
I don't have any discussion to add to this.  One study is one study, and this one is clearly negative.

Status of Vitamin-D
There is sometimes discussion of Vitamin-D as a possible type-1 prevention or cure.  So I looked for human trials of vitamin D in people with type-1 diabetes.  I found six (listed below); two are complete, two are still recruiting, one was only looking a vascular side-effects and the last was the ongoing Haller cord blood study (where they also gave vitamin D and Omega-3s).  Below are quotes from the abstracts of the completed studies:
RESULTS: No significant differences were observed between calcitriol [vitamin-D] and nicotinamide groups in respect of baseline/stimulated C-peptide or HbA1c 1 year after diagnosis, but the insulin dose at 3 and 6 months was significantly reduced in the calcitriol [vitamin-D] group. CONCLUSIONS: At the dosage used, calcitriol [vitamin-D] has a modest effect on residual pancreatic beta-cell function and only temporarily reduces the insulin dose.
RESULTS: Safety assessment showed values in the normal range in nearly all patients, regardless of whether they received 1,25(OH)(2)D(3) [vitamin-D3] or placebo. No differences in AUC C-peptide, peak C-peptide, and fasting C-peptide after a mixed-meal tolerance test between the treatment and placebo groups were observed at 9 and 18 months after study entry, with approximately 40% loss for each parameter over the 18-month period. A1C and daily insulin requirement were similar between treatment and placebo groups throughout the study follow-up period. CONCLUSIONS: Treatment with 1,25(OH)(2)D(3) [vitamin-D3]at a daily dose of 0.25 microg was safe but did not reduce loss of beta-cell function.
So basically, one study found slight benefit and the other one found no benefit.

It is important to remember that both of these studies involved giving vitamin-D to people who already had type-1 diabetes.  Neither of these studies address the question of preventing type-1 diabetes by raising the overall level of vitamin-D prior to diagnosis.  That question is complex, and deserves it's own blog posting.  (If I have time.)  As a quick summary, I think it is fair to say that people who live nearer the equator are less likely to get type-1 diabetes than people who live nearer the poles.  Some have attributed this to the higher levels of sunlight and vitamin-D in those places, but there are many differences between people who live near the equator as compared to the poles: genetics are different, poverty is different, lifestyle is different, diet is different, etc.  So I don't find these sorts of population based studies very convincing.   A few studies which compare different populations within the same country do support the idea that vitamin-D lowers the rates of type-1 diabetes, but there are also studies that don't support this idea.   I don't think the correct answer is obvious at this time.

In general, I think it is a big mistake to compare populations in different countries (no matter what is being studied).  It is often a classic "apples vs. oranges" comparison mistake.  In the Americas (for example), this argument boils down to the idea that Canadians and Americans have a much higher type-1 diabetes rate than Mexicans.  However, there are many huge differences between Mexico and the other two countries, and to focus on vitamin-D as the cause requires more data than just the country vs. country comparison.  On the other hand, across the Atlantic the comparison boils down to high rates of type-1 diabetes in Europe compared to low rates in Africa.  Again: these are very different places!  Therefore, I do not think that comparing type-1 rates in different countries will ever provide enough support to the idea that vitamin-D has an impact on these rates.  I would limit my research to comparisons of similar populations within one country (or possibly in similar countries such as Canada vs. USA or different Nordic countries). 

Here are abstracts for the two that are complete:

Here are the clinical trial records (first two are complete, rest still recruiting):

Joshua Levy
All the views expressed here are those of Joshua Levy, and nothing here is official JDRF or JDCA news, views, policies or opinions. 
Blog: http://cureresearch4type1diabetes.blogspot.com
Web: http://joshualevy.pbworks.com/DiabetesCureReadyForHumanTrials