*

Brain monitoring shows tirzepatide reduces food cravings

*

Binge-eating signals were suppressed in the nucleus

accumbens,

the brain's reward center

*

Effect seen in a single patient was only temporary

*

GLP-1 drugs may need redesign for lasting impact on eating

disorders, researcher says

By Nancy Lapid

Nov 17 (Reuters) - Researchers monitoring the brain

activity of a patient with a severe binge-eating problem

reported that Eli Lilly's ( LLY ) GLP-1 weight-loss drug appeared to

temporarily suppress food-craving signals in the "reward center"

of the brain.

These are the first direct measurements of brain activity in

a person receiving tirzepatide, sold as Mounjaro for diabetes

and Zepbound for weight loss, shedding light on the treatment's

impact on so-called food noise.

The report, published on Monday in Nature Medicine,

describes the effect of tirzepatide on a single individual, and

the findings cannot be generalized to others, the researchers

cautioned. But it may suggest a role for future versions of

Mounjaro or other GLP-1 drugs in treating certain eating

disorders, they said.

"Hopefully this report inspires some rigorous investigation

of that possibility," said study leader Dr. Casey Halpern of the

Perelman School of Medicine at the University of Pennsylvania.

The study followed four patients participating in the first

human trial of deep-brain stimulation for treating

loss-of-control eating disorders such as binge-eating and

bulimia.

The plan was to monitor activity in the brain's reward

center, or nucleus accumbens, and use a surgically implanted

device to send electrical impulses to block signals that "ramp

up" before binge-eating episodes, Halpern said.

One patient's doctor had prescribed tirzepatide before the

electrodes were implanted to treat her type 2 diabetes and

obesity. During the first few months of electrode monitoring,

she reported no food preoccupation and her nucleus accumbens

food-craving signals were silent.

Study participants not taking tirzepatide showed the typical

elevated activity in the nucleus accumbens and frequent episodes

of food preoccupation.

The striking quiet in her nucleus accumbens signaling and

food preoccupation suggests that tirzepatide was responsible for

the temporary quieting of food noise in this patient, the

researchers said.

"Activity in her nucleus accumbens was so quiet that it

almost made us think our system wasn't working," Halpern said.

DRUG IMPACT FADES OVER TIME

Five months later, the researchers saw signs that

tirzepatide's effects on this patient's behavioral disorder

were temporary, and "food noise" was breaking through.

They detected nucleus accumbens activity consistent with

binge-eating, and the patient reported episodes of severe food

preoccupation.

The reason tirzepatide's effect on out-of-control eating was

only temporary in this case is likely because the drug was

designed and optimized for diabetes and weight loss, not for

binge-eating disorders, Halpern surmised.

Current popular weight-loss drugs mimic hormones found in

the small intestine and pancreas and are not designed to impact

the brain's reward mechanisms.

To have a lasting effect on severe food preoccupation, GLP-1

drugs would need to be redesigned to impact the nucleus

accumbens and optimized for mental health, Halpern said.