When will retatrutide be available in the UK

The question we are being asked most often by patients who are paying attention to the weight-management pipeline: when can I have retatrutide in the UK. The honest answer is that nobody knows the exact date, and pretending otherwise would be dishonest medicine. What we can do is walk through the regulatory journey from where retatrutide is now to where it has to get to before we can legally prescribe it, and tell you what our commitment is at each stage.

What has to happen between a Phase 3 trial and a prescription

A new medication has to clear several gates before a UK doctor can write a prescription for it.

Complete the Phase 3 programme. A Phase 3 trial tests the medication at scale against placebo and against existing treatments. Eli Lilly is running eight Phase 3 trials in the retatrutide programme covering obesity, type 2 diabetes, cardiovascular outcomes, knee osteoarthritis and other indications. Some have reported; the remainder are due across the rest of 2026.

Submit the full data package to the MHRA. The Medicines and Healthcare products Regulatory Agency is the UK regulator that licenses medication for use here. The manufacturer files a comprehensive dossier covering manufacturing, trial results, safety data, dosing, labelling and packaging.

MHRA scientific review. The MHRA's assessors review the dossier, ask questions, sometimes require additional data. A review of a medication of this profile typically runs for nine to twelve months from submission, sometimes longer.

Decision. The MHRA either grants a marketing authorisation, refuses it, or grants it with conditions (additional studies required, specific patient groups excluded, restricted distribution).

Post-licence steps. A pricing decision through the National Institute for Health and Care Excellence affects NHS access but does not block private prescription. Distribution channels are set up. The medication appears on the wholesaler menus we order from at our own pharmacy.

Only once all of the above is complete can a UK doctor legally prescribe retatrutide.

Where retatrutide is in the journey right now

As of May 2026: the Phase 3 programme is partway through. TRIUMPH-1, the headline obesity trial, reported positive results on 21 May 2026. Further Phase 3 readouts are expected through the rest of 2026.

Eli Lilly has stated the intention to file with regulators including the MHRA. A submission to regulators is plausible in late 2026 or early 2027 if the remaining trial readouts go well. A UK licensing decision, if everything proceeds without delay, could follow in late 2027 or 2028.

None of those dates is guaranteed. Phase 3 readouts can surface new safety signals that delay or block a submission. A regulator can request more data and stop the clock. The company can choose to prioritise other markets. Honest medicine acknowledges this; we are stating the range of what looks plausible, not predicting a date.

What we cannot legally do before licensing

We cannot prescribe retatrutide in the UK before the MHRA grants a licence. There is no clinical-trial route into a private clinic outside the official trial programme. There is no compassionate-use route for an obesity medication that has approved alternatives already available.

We are also clear about what we will not do: we will not source unlicensed retatrutide from overseas suppliers or compounded versions from grey-market pharmacies. The medication has not yet been quality-assured by a regulator. The compounded versions circulating online are not the same product that has been studied in the trials, and the supply chain is unverified.

If you are already using retatrutide

We know that several thousand people in the UK have already started self-sourcing retatrutide through grey-market channels. If that is you, we are not going to lecture you and we are not going to refuse to see you.

What we will do is offer you an honest clinical assessment. A consultation to understand what you are using, where you are sourcing it, what dose you are on, and what your goals are. A baseline examination. A tailored blood panel to check that your organs are not being put under strain and that no harm is being done. Ongoing monitoring at a sensible cadence so that if something starts to drift, we catch it early.

We will not prescribe or supply unlicensed retatrutide. That part of the line is not flexible because the regulatory framework does not allow it. What we will do is keep you safer than you would be without medical eyes on what you are doing, and have an honest conversation about whether a licensed alternative (Wegovy, Mounjaro or Rybelsus) would actually do the job you are trying to do, often with stronger evidence and a known supply chain.

This is the same harm-reduction stance we take with other patients using substances ahead of, or outside, the licensed pathway. Monitoring, not endorsement. No judgement, just clinical work.

Our commitment when retatrutide is licensed

If and when the MHRA grants a marketing authorisation for retatrutide, our position is straightforward.

We will assess the licensed product against the existing options on the basis of the licensed dose, the licensed indication, and the published safety data.

We will integrate it into our weight-management formulary as soon as it is available through legitimate wholesale supply. Our in-house pharmacy gives us a head start on this; we are not waiting on a third-party pharmacy to source the medication.

We will offer it to patients for whom it is the right choice based on the licensed indication, your clinical picture and your preference. The decision will be made in consultation, as it is for every medication we prescribe.

We will not push retatrutide on patients doing well on Wegovy, Mounjaro or Rybelsus. If your current treatment is working, the right answer is usually to keep going. Switching for the sake of newness is not the same as switching for the sake of evidence.

We will write a clear update for every patient on weight-management treatment with us, explaining the new option, who it is suitable for, and whether it changes the conversation for them specifically.

What you can do in the meantime

If you are not yet in treatment and the weight management you need is meaningful, the right answer is to start with what is available now. The injectable options today produce weight loss of 15 to 22.5 percent on average; that is clinically transformative and worth doing. Waiting twelve to twenty-four months for a medication that may or may not arrive is not the right trade.

If you are already in treatment and reading this, the practical implication is that the menu of options is going to expand. We design treatment plans to be flexible. The drug, the dose and the route of administration can all change as the evidence and the options change.

If you want to be told the moment we are able to prescribe retatrutide, tell us at your next review. We will add you to a register of patients to contact when the licence is granted.

The honest summary

Retatrutide is real, the trial data is genuinely promising, and the regulatory journey is in motion. The journey is also long, conditional, and not guaranteed to end with a UK licence. What we will not do is pretend we have an inside line on the timing. What we will do is be ready: ready to assess the medication the day it lands, ready to integrate it into our pharmacy, ready to talk to you about whether it is the right next step.

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