The End of Diabetes: The Eat to Live Plan to Prevent and Reverse Diabetes

Remember Dr. Denise Faustman? Dr. Faustman is about as close as the type 1 diabetes world comes to having a celebrity researcher. Her lab, based at Massachusetts General Hospital, has given folks with diabetes a lot of hope—and also generated plenty of controversy.

The BCG Vaccine

In 2018, Dr. Faustman’s team released the first results from a Phase I trial of a novel but appealingly simple and non-invasive remedy that could make blood sugar management much easier for patients with type 1 diabetes. The treatment? The bacillus Calmette-Guérin (BCG) vaccine, which has been used to prevent tuberculosis for a century. The BCG vaccine is one the oldest, longest-studied and best-understood vaccines; it is inexpensive and considered very safe. It is administered to as many as 100 million newborns across the globe annually.

The early effects were encouraging: patients with type 1 diabetes who received just two doses of the BCG vaccine, spaced four weeks apart, achieved markedly lower A1c levels when compared to a control group. This result was first observed 3 years after the vaccine administration and continued for the next five years of follow-up. Participants receiving the experimental treatment had an HbA1c of just 6.18%, significantly lower than participants who received a placebo (7.07%). These results understandably created a lot of enthusiasm in the diabetes community.

The Authorities Push Back

The good results, however, also attracted some pushback from important diabetes authorities. The American Diabetes Association and JDRF took the unusual and striking step of co-authoring a joint statement to highlight “limitations” to Dr. Faustman’s research. The study, according to the statement, was minuscule – “nine people at the five-year time point, and three people at the eight-year time point” – and did “not provide enough clinical evidence to support any recommended change in therapy at this time.” While couched in cautious and moderate language, the letter clearly hoped to smother the hype that the BCG learn about had kindled.

A 2021 profile in Healthline stated that Dr. Faustman has now been “effectively shunned by the research community.” She has had to seek funding outside of the usual sources – something she’s done with aplomb, raising millions from private donors.

How BCG Might Work

Dr. Faustman hasn’t been as much in the news too much lately, but rest assured, she’s still working. And at last month’s ADA Scientific Sessions conference, we received an update to her ongoing work on the BCG vaccine. The team is still learning how and why BCG appears to work the way that it does.

The BCG vaccine is old, but its proposed mechanism in treating type 1 diabetes is new and surprising. BCG does not appear to restore insulin production, nor does it modify insulin sensitivity. So, what could explain the purported improvements in glycemic control?

Many experts have theorized that our immune systems have become less robust because our society is so much cleaner than it used to be. This idea, the so-called ‘hygiene hypothesis,’ also seems like a pretty good explanation for why type 1 diabetes is more common than it used to be. Dr. Faustman believes that the vaccine may aid kick parts of the immune system into action, a mechanism that used to happen naturally back when we had a messier society. In particular, BCG helps trigger the proper role of “Tregs,” immune cells that are known to be dysfunctional in people with type 1 diabetes. Over a period of three years, participants in the study saw their Treg function slowly return to normal. This change also causes the immune system itself to burn more blood glucose, a shift that creates big glycemic improvements.

Interestingly, the BCG vaccine seems effective in patients that developed T1D during childhood (< 21 years), but not those that developed the condition as adults.

More Trials Planned

Meanwhile, several other trials of BCG have begun. A Phase II study is happening right now, and will monitor the effects of the treatment in more detail and with more participants; if the good results are confirmed, it could help allay the concerns raised by the research community about Dr. Faustman’s work. In addition, the Faustman lab is targeting a larger pediatric trial, which will test the vaccine in 150 adolescents, some with well-established type 1 diabetes, some newly diagnosed. Perhaps younger patients have an even greater opportunity to benefit.

The appeal of the BCG vaccine is obvious—a simple jab or two that could confer years of significant blood sugar improvements? Who wouldn’t be excited? But it would be best to persist to evaluate Dr. Faustman’s results with caution, given the skepticism of other researchers. Even if she’s right that BCG is a kind of silver bullet that can deliver durable A1c improvements, it will be years before she’ll have the data to make the case.

Diabetes Daily

The End of Diabetes: The Eat to Live Plan to Prevent and Reverse Diabetes