Metabolic peptide trial-record titration reference

Tirzepatide's UK research and licensed dosing schedules are anchored to the SURMOUNT and SURPASS Phase 3 programmes, which used identical titration steps. Weekly subcutaneous administration is the only route studied; doses escalate at four-week intervals to manage gastrointestinal tolerability. The 15 mg maintenance dose used in SURMOUNT-1 produced ~22% mean weight reduction at 72 weeks.

Semaglutide is available in three MHRA-licensed forms with distinct dose schedules. Wegovy uses a 16-week titration to 2.4 mg weekly subcutaneous (STEP-1 schedule). Ozempic titrates to 1 mg or 2 mg weekly. Rybelsus is the only oral GLP-1 — 14 mg daily after a 60-day titration, with strict empty-stomach administration. Dosing schedules differ; the molecule does not.

Retatrutide is not MHRA-licensed and is supplied for laboratory research only. The doses below describe the schedule used in the Jastreboff et al. Phase 2 trial (NEJM 2023) — they are not protocols for human use. Phase 3 TRIUMPH-1 has retained the same titration framework but the registrational dose schedule may differ at marketing authorisation.

Liraglutide is MHRA-licensed as Saxenda (3 mg daily for weight management) and Victoza (1.8 mg daily for T2DM). Daily dosing distinguishes it from weekly semaglutide and tirzepatide — a reflection of the 13-hour half-life from C-16 fatty-acid albumin binding rather than the C-18 fatty diacid used in next-generation analogues.