Retatrutide in South Africa: where it stands and how it compares with Ozempic

Status at a glance (8 October 2026)

• South Africa: a search of the SAHPRA medicine register for "retatrutide" and for its development code LY3437943 on 8 October 2026 returned no results. It cannot be prescribed or dispensed here.
• United States: not approved. Lilly says in its 23 July 2026 press release that it plans to submit a Biologics License Application to the FDA in the first quarter of 2027.
• Europe and elsewhere: no approval anywhere. Lilly has said its data package supports "global submissions", but we found no public confirmation of a filing with the European Medicines Agency or SAHPRA.
• Evidence: five phase 3 trials have reported positive topline results, and the first two full papers were published on 29 September 2026.

What retatrutide is

Retatrutide (development code LY3437943) is a single molecule that activates three hormone receptors: GLP-1, GIP and glucagon. That is why it is often called a "triple agonist". For comparison, semaglutide, the active ingredient in Ozempic and Wegovy, acts on the GLP-1 receptor only, and tirzepatide (Mounjaro) acts on GLP-1 and GIP. The added glucagon activity is thought to increase energy use, but whether that translates into better long-term health outcomes is still being studied. In trials it is injected under the skin once a week, starting at 2 mg and increased in four-weekly steps to 4 mg, 9 mg or 12 mg.

The clinical trial record so far

Phase 2 (NEJM, 2023)

The first large obesity study, led by Ania Jastreboff at Yale and published in the New England Journal of Medicine in 2023, randomised 338 adults with obesity, or with overweight and a weight-related condition. After 48 weeks, average weight change was -24.2% on 12 mg compared with -2.1% on placebo. Side effects were mainly gastrointestinal, dose-related and mostly mild to moderate. The trial also recorded dose-dependent increases in heart rate that peaked at 24 weeks.

The phase 3 TRIUMPH programme

Lilly's phase 3 obesity programme, called TRIUMPH, began in 2023. According to Lilly, the initial four registration trials enrolled more than 5 800 people. A separate programme, TRANSCEND, tests retatrutide in type 2 diabetes. The results reported so far are:

Two different ways of counting results appear in these reports, and they give different numbers. The "efficacy estimand" estimates the effect if everyone had stayed on treatment. The "treatment-regimen" (intention-to-treat) estimand counts everyone who was randomised, including people who stopped. In TRIUMPH-1, for example, the 12 mg result was -28.3% by the first method and -25.0% by the second. The peer-reviewed TRIUMPH-1 paper in the New England Journal of Medicine reports the treatment-regimen figures: -17.6%, -23.7% and -25.0% on 4 mg, 9 mg and 12 mg, against -3.9% on placebo. The same paper reports less knee pain in participants with osteoarthritis and fewer breathing interruptions in those with obstructive sleep apnoea.

In a blinded extension of TRIUMPH-1, 532 participants with a starting BMI of 35 or more who had completed 80 weeks and tolerated their dose continued to 104 weeks. Those on 12 mg reached an average loss of 30.3% (efficacy estimand). Because only people who completed the main trial and tolerated the medicine were included, this figure describes a selected group, not everyone who starts treatment.

Side effects and discontinuation

The side effects reported so far are similar in type to those of other incretin medicines, but some were common at the higher doses. In TRIUMPH-1, nausea affected 28.6%, 38.4% and 42.4% of people on 4 mg, 9 mg and 12 mg, compared with 14.8% on placebo, and vomiting affected up to 25.3% on 12 mg. Dysesthesia, an unusual skin sensation such as tingling or burning, was reported by 12.5% on 12 mg compared with 0.9% on placebo. Most cases were mild to moderate. The proportion of people who stopped because of side effects was 11.3% on 12 mg compared with 4.9% on placebo. In TRIUMPH-3 it was 13.5% on 12 mg compared with 4.8% on placebo (Lilly press releases, 21 May and 23 July 2026).

Some important questions remain open. TRIUMPH-3 was not designed to prove a heart benefit: Lilly reported 44 major cardiovascular events (MACE-5) on retatrutide and 52 on placebo, a difference that was not statistically significant. A dedicated cardiovascular outcomes trial is still under way. Longer-term safety data will also only come with time and regulatory review.

Retatrutide compared with Ozempic

A direct comparison is not possible yet. We found no reported trial that tested retatrutide head-to-head against semaglutide. Any comparison therefore puts results from separate trials side by side, with different participants, durations, doses and analysis methods. It shows the scale of the results, not which medicine is better for a given person.

It also matters which semaglutide product you compare with. In South Africa, Ozempic is registered for type 2 diabetes, not for weight management, and its South African package insert describes doses of up to 1 mg once a week. Wegovy contains the same molecule at up to 2.4 mg a week and is the version registered for weight management. The large semaglutide weight-loss trials used the Wegovy dose.

Sources: TRIUMPH-1 (Jastreboff et al., NEJM, 29 September 2026); TRIUMPH-2 (Lilly, 23 July 2026); STEP 1 (Wilding et al., NEJM, 2021) and STEP 2 (Davies et al., The Lancet, 2021), as summarised in the SAHPRA-approved Wegovy package insert.

On these numbers, retatrutide's average weight loss in its own trials was larger than semaglutide's in the STEP trials. That is the main reason for the interest in it. But retatrutide's trials were longer, its participants started heavier, and its higher doses brought more people to stop treatment because of side effects. Semaglutide, on the other hand, has a proven cardiovascular benefit and years of real-world safety monitoring that retatrutide does not yet have.

Can you get retatrutide in South Africa?

No, not lawfully. Under the Medicines and Related Substances Act 101 of 1965, a medicine must be registered with SAHPRA before it can be sold here, and retatrutide is not on the register. Outside a clinical trial, there is no legal route to get it in South Africa. Lilly itself states that retatrutide "cannot be legally sold or marketed for human use".

Products labelled "retatrutide" are nevertheless advertised locally as "research peptides" or "not for human consumption", usually as powder vials. A Mail & Guardian investigation published on 2 July 2026 found them sold through social media and gyms. In that report, SAHPRA's regulatory compliance manager Mokgadi Fafudi said retatrutide "is still under clinical investigation" and is not approved for routine sale in any market. SAHPRA urged anyone who had bought such products from an unofficial source to stop using them.

SAHPRA's public warning on peptide products lists the risks of unregistered injectables: infections, contamination, hormonal disruption, harmful drug interactions and unknown long-term effects. It notes that registered GLP-1 medicines are supplied ready to use in pre-filled pens or vials, and that powder forms are not registered. On 23 May 2026, SAHPRA and the South African Pharmacy Council also announced enforcement action, including seizures and a recall, against a Pretoria pharmacy that was making unregistered semaglutide and tirzepatide products. They noted reports of adverse events, including hospitalisations. A product sold as retatrutide has not been checked by any regulator, so there is no way to know what it contains or how much.

What this means if you are considering treatment now

Medicines that have been assessed by SAHPRA are available in South Africa, including semaglutide (Ozempic for type 2 diabetes, Wegovy for weight management) and tirzepatide (Mounjaro). Whether any of them suits you is a decision for you and your doctor, based on your health, other medicines and goals. If you are prescribed semaglutide, our semaglutide pharmacy rating compares registered pharmacies on delivery, prescription handling and support, and How we rate explains the criteria. Retatrutide may become an option in future, but approval is not guaranteed, and a South African registration would require a separate application to SAHPRA. No timeline for that has been announced.