How the hunger for a new weight loss drug is feeding an industry of fakes

Excitement around the creation of a new drug, especially one showing early promise in clinical trials, is often celebrated by those developing it.

But new weight-loss drug retatrutide has become a headache not only for Eli Lilly, the pharmaceutical company behind it, but for regulators in the UK and around the world.

The jab has not yet been approved for human use by any regulatory body.

But illicit, counterfeit dupes of retatrutide are currently flooding the black market.

Experts have told the BBC this is one of the first times they have seen copycat versions of an experimental drug, still in the throes of being tested, become so widely available.

Vials purporting to be "reta" as it's become known, are being sold in the UK in gyms, nail and beauty salons, hairdressers, on social media and even by flower sellers on the street.

"The world has gone mad," pharmacist and director of 24 HR Pharmacy, Sehar Shahid says. "People are effectively injecting an illegal drug and thinking it's safe.

"It's become so normalised people openly talk about their dealers, where's best to get it from and post all over social media."

One quick flick through my socials and I can order a batch of a drug billed as retatrutide in minutes - although I would have no proof what it's actually made of, what its effects would be and where it's come from.

Keen users are posting before and after "reta" pics on their TikTok feeds, describing how it has silenced food noise, helped them shed pounds and lose inches, with some saying it's completely transformed their lives.

The problem? Despite positive results in its most recent clinical trials, real retatrutide is still being tested for its safety and efficacy.

Only 50% of drugs in this Phase III stage of testing in the US are eventually approved by the Food and Drug Administration (FDA), so there is no guarantee retatrutide will ever hit the market. The high rate of failure is primarily down to drugs not working as well in large, diverse human populations as they do in smaller early tests, or because they reveal unexpected safety hazards.

And the current, fake versions available may not resemble what's being developed in the safe confines of the laboratory.

Eli Lilly's website carries a strong warning "no one should take anything claiming to be retatrutide outside of a Lilly-sponsored clinical trial".

"Illicit retatrutide products may contain unknown ingredients, harmful contaminants and impurities. These products may also have too much or too little active ingredient, or the wrong ingredient entirely".

Despite this, it seems there are plenty of people willing to take that gamble.

"Young fit patients are coming into hospital with nausea, vomiting, diarrhoea, in some cases kidney failure," says endocrinologist, Prof Donal O'Shea.

He says some personal trainers are not only supplying their clients with the drug, they are also injecting them with it.

"The patients have no idea how much they have been taking, or even what they've been injected with."

Tom Davies says he nearly ended up in hospital after accidentally overdosing on a fake version of retatrutide. He ordered it from a Chinese supplier after friends at his gym recommended it.

"It was horrendous," says the 20-year-old from Brighton. "My body felt so under pressure, I was so bloated, it was like someone had dropped a 20kg weight on my stomach.

"For 72 hours I had really bad diarrhoea and nausea. I thought, if this continues I'm going to end up in A&E."

Tom later realised he had given himself eight times the recommended dose. Depending on what is ordered, copycat retatrutide can arrive needing to be mixed with sterile, bacteriostatic water which requires various calculations.

Dr Nas Khattak, a research doctor based in Chester, has been screening patients for one of Eli Lilly's Phase III clinical trials. He says those sourcing fake versions are in effect behaving as lab rats without any medical oversight.

"If users who buy it online become their own doctor, they're taking a huge risk," he warns.

He says trial participants need to meet strict criteria before they are given the green light to start taking the real drug or a placebo.

"We request their GP record, we make sure that they're emotionally well. They'll have suicide, self-harm, mental health assessments - and this is all done by doctors.

"Then we come back and have a look at the blood tests, have a look at everything, and then we think whether they're suitable or not."