Injectable vs oral · checked 2026-08-07
Retatrutide vs orforglipron: two Eli Lilly candidates, two very different stories
Both from Eli Lilly, both still not licensed in the UK — but orforglipron is already FDA-approved in the US (as Foundayo), while retatrutide hasn't even filed yet. One is ahead on the regulatory path; the other is ahead on the trial numbers.
| Orforglipron (Foundayo) | Retatrutide | |
|---|---|---|
| Administration | Daily oral tablet | Weekly injection |
| Mechanism | GLP-1 receptor only (non-peptide, small molecule) | GLP-1 + GIP + glucagon receptors |
| US status | FDA-approved (April 2026, as Foundayo) | Not yet filed — FDA submission planned Q1 2027 |
| UK status | Not licensed — MHRA paediatric investigation plan agreed Dec 2025; NICE appraisal guidance expected Nov 2026 | Not licensed — no MHRA/NICE engagement on record yet |
| Reported weight loss | ATTAIN-1: up to 11.2% at week 72 | Up to 30.3% (TRIUMPH-1) |
Ahead on approval vs ahead on results
These are genuinely different trade-offs, not one drug simply beating the other.
Orforglipron's advantage
It's a small-molecule pill, not a peptide — easier to manufacture and already FDA-approved in the US. It's meaningfully further along the regulatory path than retatrutide, even though its weight-loss numbers are much smaller.
Retatrutide's advantage
The triple-receptor mechanism is producing roughly triple the weight loss of orforglipron in trials — but it's an injection, not a tablet, and hasn't even reached FDA filing yet.
The practical takeaway today
Neither is available in the UK. Orforglipron is closer to a UK decision (MHRA and NICE both have live paperwork on it) but is a much smaller effect size. Retatrutide's trial results are the strongest in the whole GLP-1 field so far, but it's earlier in its own regulatory journey than orforglipron.
Retatrutide UK statusFull evidence & regulatory record
Orforglipron / Foundayo trackingGLP1 Tablets →
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