Retatrutide Evidence Base Graded by GRADE: What the Clinical Data Actually Show

Current status: Retatrutide is investigational and not FDA-approved. It is not available for public use; federal law does not permit it to be compounded, and HealthRX does not offer it.

Evidence directly relevant to published and registered clinical research

The evidence is limited to clinical research. It does not establish an approved indication, public treatment protocol, or patient-specific recommendation.

Published phase 2 evidence

The peer-reviewed phase 2 obesity trial randomized 338 adults and reported body-weight and safety outcomes over 48 weeks. Gastrointestinal adverse events were the most frequently reported, and increases in heart rate were observed. The study evaluated protocol-defined doses in research participants; it did not create an approved dose or public treatment protocol [1].

Registered and sponsor-reported phase 3 evidence

ClinicalTrials.gov lists TRIUMPH-1 as a completed phase 3 study with 2,335 participants [2]. In 2026, Lilly announced topline results from several phase 3 trials. Those sponsor reports add evidence, but they are not substitutes for complete peer-reviewed publications or FDA review [4].

Current regulatory record

FDA states that retatrutide is not a component of an approved drug, has not been found safe and effective for any condition, and cannot be used in compounding under federal law [3].