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ReHuman trials

Retatrutide protocol

A once-weekly triple agonist (GIP, GLP-1 and glucagon receptors). Phase 3 is done; it is not approved anywhere yet. Sold in the Philippines only as a research peptide.

Investigational · not approved anywhereNot registered with the Philippine FDA
ProtocolMixingResultsSide effectsHow it worksSources

The protocol at a glance

Once a week, same day each week. Every trial started at 2 mg and stepped up every 4 weeks to the assigned dose.

WeeksWeekly amount in the trials (highest group)
1–42 mg
5–84 mg
9–128 mg (phase 2) · 9 mg target group in TRIUMPH-1
13+12 mg

Phase 2 groups: 1, 4, 8 or 12 mg (ClinicalTrials.gov NCT04881760). TRIUMPH-1 groups: 4, 9 or 12 mg, all starting at 2 mg and stepping up every 4 weeks (Lilly, May 2026).

Community reports

Community reports commonly start lower than the trials, around 0.5 mg a week, then step up to 1, 2 and 4 mg with at least 4 weeks at each amount. Some drop to about 1 mg a week once they reach their goal.

What people say they do, collected from community discussions. Not tested in a trial; shown so you can compare it with the evidence above.

Mixing calculator

Enter the vial size, the water you add and the amount you want to draw; it gives the mark on a 100-unit (1 mL) insulin syringe.

Draw to – units

What the trials found

Average body-weight change in the two main obesity trials:

−24.2%12 mg · 48 wks (phase 2)
−19.0%4 mg · 80 wks (TRIUMPH-1)
−25.9%9 mg · 80 wks (TRIUMPH-1)
−28.3%12 mg · 80 wks (TRIUMPH-1)

Placebo: −2.1% (phase 2, 48 weeks, 338 adults; Jastreboff et al., NEJM 2023) and −2.2% (TRIUMPH-1, 80 weeks, 2,339 adults; Lilly topline, May 21, 2026).

Side effects

  • Nausea, diarrhoea, vomiting and constipation were the most common, more frequent at higher doses and during step-ups. In TRIUMPH-1 nausea affected 29–42% on retatrutide vs 15% on placebo.
  • Dysesthesia (unusual skin sensations): 5–13% on retatrutide vs about 1% on placebo in TRIUMPH-1.
  • Heart rate rose with dose in phase 2 and eased later in the trial.
  • Stopping because of side effects in TRIUMPH-1: 4.1% (4 mg), 6.9% (9 mg), 11.3% (12 mg) vs 4.9% placebo.

How it works

GLP-1 receptor

Slows stomach emptying and signals fullness to the brain.

GIP receptor

Works alongside GLP-1 on insulin release and fat tissue.

Glucagon receptor

Raises energy use and liver fat burning. Tirzepatide does not have this part.

Sources

  • ClinicalTrials.gov NCT04881760 (phase 2 dose groups)
  • ClinicalTrials.gov NCT05929066 (TRIUMPH-1)
  • Jastreboff AM et al. N Engl J Med 2023 (phase 2 results)
  • Eli Lilly TRIUMPH-1 topline release, May 21, 2026