Diabetes drug Mounjaro approved for obesity treatment by Therapeutic Goods Administration

An in-demand diabetes drug that went viral for its weight-loss side effect has just been approved to treat obesity by the Australian regulator. Here’s everything you need to know.

An in-demand diabetes drug that went viral for its weight-loss side effect has been approved to treat obesity by the Australian regulator.

Pharmaceutical giant Eli Lilly announced on Wednesday the Therapeutic Goods Association has approved tirzepatide, sold as Mounjaro, as a weight-loss treatment.

Australian authorities had previously approved the injectable drug for type II diabetes only and told doctors to reserve supply for such patients, after a spike in off-label scripts for weight-loss sparked shortages.

The new approval applies to patients who, as measured by BMI, are obese or overweight and have at least one weight-related health condition.

Swinburne University obesity specialist Adjunct Professor John Dixon said the approval was a “significant step” and patients were not to blame for their weight.

A third of Australian adults are obese.

“I think we’ll see the introduction of people living with obesity, particularly the more severe forms, will actually for the first time, have effective therapy for their disease and won’t die prematurely,” Adjunct Professor Dixon said.

A Mounjaro injection pen. Picture: Getty Images

The drug, which costs several hundreds of dollars, is not subsidised but Eli Lilly said it would push for a PBS listing after news of its therapeutic approval.

It is the second injectable weight-loss drug to be released in Australia, with Novo Nordosk’s Wegovy, a higher-dose version of Ozempic, brought to our shores for the first-time just last month.

Some experts have hailed their arrival as a landmark opportunity to tackle rising obesity levels and its related chronic diseases, while others have reservations about the drugs’ misuse for weight-loss in already healthy people.

Surging emand has sparked ongoing shortages across the category, but Eli Lily said on Wednesday that while Mounjaro vials in some doses were limited, their prefilled injectable pens were available.

Eli Lilly Australia general manager Tori Brown said obesity affected “millions of Australians” and weight management medicines “should be recognised as important tools”.

“Lilly is committed to illustrating the significant value of Mounjaro to the federal government and securing support for equitable access of Mounjaro through the PBS for patients living with type 2 diabetes or obesity,” she said.

The company applied for a PBS listing for diabetes patients last year, but an independent committee found a “substantial price reduction” was needed to “be considered cost-effective”.

A third of Australian adults are obese. Picture: Supplied

Professor Dixon, who has served on advisory committees for drugs including Mounjaro, said the drug had “almost exactly the same effect” as bariatric surgery and reduced appetite.

“We’ve not had drugs that have been able to do this before,” he said.

“If we can use these hormones from the gut, we can change the brain’s perception of hunger, satiety and allow people to naturally lose the weight.”

He said everyone had a different “set” weight that our bodies subconsciously try to maintain - such as by releasing hormones that promote hunger or fullness - when we deviate from it.

“Diet and exercise doesn’t work for the vast majority of people,” he said.

“When we’ve got something that’s genetically primed and driven by our environment, there’s very little left for the person’s own control to deal with.

“Most healthcare professionals do not understand, do not recognise, that obesity is a serious chronic disease that we cannot cure.

“Most Australians who have the serious disease of obesity with its complication and so forth, never have any actual treatment that’s actually treating their number one disease.

“It’s rather negligent.”

He said people typically gain the weight back if treatment stops, so it needs to be taken long-term in the same way people take high-blood pressure or diabetes treatment continually.

Mounjaro cannot be accessed without a doctor’s prescription and can have some side effects, including an upset stomach, injection site-related side effects and low blood sugar.