JUNE 21, 2018
An experimental therapy for type 1 diabetes, widely derided by mainstream
diabetes researchers, lowered blood sugar levels to near normal, a small,
ongoing trial found. Patients in the trial, whose blood sugar levels have
remained near normal for five to eight years, take about one-third less insulin
than they did before, reducing their risk of hypoglycemia, in which insulin
lowers blood sugar to dangerously low levels.
The experimental treatment, a decades-old
generic vaccine for tuberculosis called bacillus Calmette-Guérin (BCG), seems
to alter both cellular metabolism and the immune system, said Dr. Denise
Faustman of Massachusetts General Hospital, senior author of the study
published Thursday in npj Vaccines. “This cheap, old vaccine is lowering blood
sugar to levels never achieved before,” she said.
While the results, from only nine patients, must
be replicated in a larger study, said Dr. Joseph Bellanti of Georgetown
University Medical Center, “if what they found is true, they really have
something here.” Bellanti, who was not involved in the research, said the
study’s eight-year follow-up and use of a placebo control arm made him
“cautiously optimistic” that two doses of the BCG vaccine “can decrease levels
of A1c,” a measure of blood glucose that predicts the likelihood of serious
complications such as stroke and kidney failure.
JDRF (formerly the Juvenile Diabetes Research
Foundation), the Joslin Diabetes Center, and several university diabetes
centers all declined to speak about Faustman’s results. She has been a voice in
the diabetes wilderness for nearly two decades, angering the establishment
diabetes community by pursuing low-tech research very different from more
popular approaches, such as embryonic stem cells and immunosupression.
Critics have gone so far as to send letters to
newspapers that covered her work apologizing to patients “on behalf of Dr.
Faustman” for “having their expectations cruelly raised.” She has also
struggled for funding, receiving much of her research support from the
private Iacocca Family Foundation, rather than in federal grants.
In Faustman’s Phase 1 clinical trial, three
participants with type 1 diabetes received two doses of BCG vaccine, a month
apart. After the vaccine showed signs of effectiveness, an additional six
patients were vaccinated five years ago, and 111 more recently. The new paper
and a presentation scheduled for a meeting of the American Diabetes Association
this weekend focus on the patients who have been followed for more than five
years.
All of those patients who received BCG had a
statistically significant change in hemoglobin A1c. A normal level is below 6.
In the vaccinated patients, A1c levels fell from an average of 7.36 before the
first dose to 6.18 after five years, holding almost steady at 6.65 in the
eighth year. In patients receiving a sham injection, levels showed almost no
change from their initial levels of 7.10: 7.07 in the fifth year and 7.22 in
the eighth.
“We wanted it to be good, but we didn’t know it
would be this good,” Faustman said.
All of the patients remain on insulin, she said,
but less of it. They are also able to monitor their blood sugar less
frequently, which can be several times an hour. (The standard of care is a
continuous glucose monitor, in which a probe is inserted into the abdomen, plus
an insulin pump.) “If we can gradually move people to where they can control
their blood sugar, their minute-to-minute lifestyle can improve dramatically,”
Faustman said.
The A1c reductions could also bring significant
health benefits. Every 10 percent drop, research shows, reduces complications
such as stroke and heart attack by about one-third. The BCG vaccine lowered A1c
levels 9 percent to 16 percent.
The new paper describes how the BCG vaccine,
which has been used for nearly 100 years against tuberculosis and is considered
extremely safe, might affect diabetes. According to studies in mice, it has two
effects. It alters the immune system so as to increase levels of T regulatory
cells; T regs keep other immune cells in check, including those that attack the
pancreas’s insulin-making cells — the root cause of type 1 diabetes. In
addition, BCG alters metabolism so cells consume higher levels of glucose, drawing
more of it out of the blood, in a process called aerobic glycolysis.
“The clinical effects and the proposed mechanism
demonstrated are exciting and add to the emerging consensus that the BCG
vaccine can have a lasting and valuable impact on the immune system,” said Dr.
Mihai Netea of Radboud University Medical Center in the Netherlands, who was
not involved in the study.
A Phase 2 clinical trial of BCG is currently
underway at Mass. General. It is testing multiple BCG doses in 150 patients
with longstanding type 1 diabetes.
Although many studies of BCG are underway around
the world in diabetes and other autoimmune diseases, including multiple
sclerosis, there has been little interest among U.S. researchers outside
Faustman’s lab.
“There is not a lot of enthusiasm because we’re
all rewarded for discovering for-profit drugs,” she said. “Potential funders
come [to my lab] and ask, ‘How can we make money off this?’”
BCG, whose one licensed manufacturer in the
U.S. is Merck subsidiary Organon Teknika, costs less than a dollar a dose.
(Faustman used a strain made by Sanofi.) The U.S. market for insulin meters and
insulin pumps is $20 billion. “With everyone thinking they need a pump and a
meter, if you come along with an inexpensive vaccine that can change this
standard of care, of course there will be pushback,” Faustman said.
https://www.statnews.com/2018/06/21/type-1-diabetes-vaccine-denise-faustman/?_hsenc=p2ANqtz--9JRZC3Rkz1sD76ZK4hbBBg10rKXNSc-gv0YvOWOZsTTCF_S6eZw96o3US1gp-5b_Z94ayFcHBZgQIsl4G4JGk1WdI3g&_hsmi=63934055
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