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What is retatrutide?

Robbie Puddick
Written by

Robbie Puddick

Medically reviewed by

Fiona Moncrieff

5 min read
Last updated June 2024

Jump to: What is the average weight loss on retatrutide? | Is retatrutide the same as tirzepatide? | Is retatrutide the same as semaglutide? | When will retatrutide be available? | Second Nature’s medication programmes

Retatrutide is a triple-action weight-loss injection manufactured by Eli Lilly. It’s undergoing later-stage human clinical trials to determine its effectiveness across a broader population.

Retatrutide is known as a ‘triple hormone receptor agonist’. This means it mimics the actions of three hormones in the body that directly affect our ability to control hunger and our blood sugar levels.

Retatrutide is likely going to be approved for individuals living with obesity and type 2 diabetes, should it receive approval from the MHRA in the UK and the FDA in the U.S.

The three hormones that retatrutide mimics are:

  1. GLP-1: Lowers appetite and blood sugar levels
  2. GIP: Lowers appetite and blood sugar levels
  3. Glucagon: Promotes fat breakdown for energy use and prevents low blood sugar levels

The triple action of retatrutide means it has a profound effect on appetite and the management of blood sugar levels and is expected to be more effective than semaglutide (Ozempic/Wegovy) and tirzepatide (Mounjaro) for weight loss.

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What is the average weight loss on retatrutide?

In 2023, a randomised controlled trial on 338 participants showed that retatrutide supported an average weight loss of 24% after 48 weeks. If you weighed 100 kg, this would be a weight loss of 24kg.

Additionally, 100% of participants on the higher doses of the drug lost more than 5% of their weight, 93% lost more than 10%, and 15% lost more than 15%.

Strikingly, 26% of participants on the highest dose of retatrutide (12 mg) lost more than 30% of their body weight.

Losing and maintaining weight loss of more than 10% is associated with significantly reducing complications related to obesity, including hypertension, type 2 diabetes, and heart disease.

A recent paper published in The Lancet showed that nearly 20% of participants in lifestyle interventions without medications gain weight, around 40% lose between 1-10% of their body weight, and just 13% lose more than 10%.

So, combining retatrutide with a lifestyle intervention leads to significantly greater weight loss than lifestyle interventions without medication.

Is retatrutide the same as tirzepatide (Mounjaro)?

Retatrutide and tirzepatide are different drugs with different chemical compositions. While retatrutide mimics three hormones to support weight loss, tirzepatide mimics two.

Still, weight loss outcomes on retatrutide and tirzepatide are similar based on the research conducted so far.

Tirzepatide supports an average weight loss of around 25% after 52 weeks. On retatrutide, it’s around 24% after 48 weeks.

However, as we don’t have longer-term research investigating the impact of retatrutide on weight loss after 48 weeks, it’s unclear whether patients would continue to lose weight beyond this.

Additionally, losing over 20% of your body weight in one year is quite sufficient for most and would lead to substantial health improvements. Not everyone would necessarily need to lose more than this to promote good health in the long term.

Is retatrutide the same as Ozempic (semaglutide)?

Retatrutide and Ozempic (semaglutide) are different drugs with different chemical compositions.

While retatrutide mimics three hormones to support weight loss and blood sugar levels, Ozempic only mimics one.

Retatrutide also appears to support more significant weight loss than Ozempic. Research suggests that Ozempic supports an average weight loss of around 6 kg after 40 weeks. On retatrutide, it’s closer to 20kg.

However, Ozempic isn’t approved for weight loss in the UK and can only be prescribed to patients living with type 2 diabetes.

Retatrutide is yet to receive approval in the UK, but it’s likely to be approved for weight loss and type 2 diabetes.

When will retatrutide be available?

It’s unclear when retatrutide will be available in the UK or the U.S. It’s likely it won’t be available for several years, with 2028 being the earliest possible date. This assumes that the drug passes later-stage human trials now underway.

Eli Lilly is currently expanding its TRIUMPH programmes to investigate the impact of retatrutide on patients living with obesity in broader populations.

These later-stage trials are known as phase 3 trials. Phase 3 trials are larger human trials that aim to investigate a medication’s effectiveness in a larger, more diverse population.

Retatrutide has already passed earlier trials, known as phase 1 and 2 trials, which primarily investigate the drug’s safety, dosing schedule, and effectiveness over a shorter time frame in smaller groups of participants.

If retatrutide is shown to be safe and effective, Second Nature may add the drug as an option alongside its medication-supported programmes using Wegovy and Mounjaro.

We believe there’s no point in taking medications without changing habits

Weight-loss injections are designed as additional tools for healthy lifestyle change and shouldn’t be considered lifelong medications.

Instead, they should be used to help you kickstart your weight-loss journey whilst you focus on building new, healthy habits.

Consider the use of antidepressants for people living with depression. They’re not designed to cure the condition. Instead, they’re designed to allow room for therapy to treat the condition’s underlying cause.

Mounjaro and Wegovy are similar. These medications can help silence food-related thoughts and also give you a boost of confidence with more immediate weight-loss results.

This helps to buy you the time and headspace to understand why your body may have struggled to lose weight previously, and to build new long-term healthy habits.

The core focus of our medication programmes is to calm down the feeling of food noise, lower your cravings, and allow you to build healthier habits to keep the weight off for good.

The ultimate goal is to make losing weight feel second nature.

Second Nature’s medication programmes

Second Nature has two medication-supported programmes: a Wegovy weight-loss programme and a Mounjaro weight-loss programme.

If you’ve made the decision to try Wegovy or Mounjaro (assuming you’re eligible), why should you choose Second Nature over other medication providers?

For peace of mind.

Second Nature has worked with the NHS for over 6 years providing weight-loss programmes across the UK.

Whilst our Wegovy and Mounjaro weight-loss programmes are private and not currently used by the NHS, we’ve built the programmes with a focus on scientific evidence, patient safety, and data security.

We hope that our 6+ years of working with the NHS and building a track record of effective weight-loss results will give you peace of mind to give us a try.

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