Black-market retatrutide users lose half the weight seen in Lilly trials
Among 378 subjects, 57% sourced the unapproved drug from online or telehealth vendors and 29% from compounding pharmacies, the analytics firm reported.
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By Maren Holt · Senior Reporter, GLP-1
Aug 24 03:00 ETSource: Partnership for Safe Medicines
The wire
- 01A Massachusetts data analytics company found non-trial retatrutide users lost 4.7%, 5.3% and 7.2% of body weight at three, six and twelve months, versus 5.7%, 11.9% and 15.5% in Eli Lilly trials.
- 02Telehealth operators and pharmacists face evidence that gray-market incretin supply may be underdosed or mislabeled, with vendors importing from facilities of unknown sterility and some faking certificates of analysis.
- 03Peer review of the study is ongoing; the analysis is observational, self-reported and cannot confirm what the 378 subjects actually injected.
From the source
Read at safemedicines.orgAugust 24, 2026: Study finds black market retatrutide is not as effective as the clinical trial versions
A study by a Massachusetts-based data analytics company found that people taking Eli Lilly’s experimental weight loss drug, retatrutide, outside of clinical trials lost significantly less weight than patients participating in the trials. Black market users lost an average of 4.7%, 5.3%, and 7.2% of their weight after taking “reta” for three months, six months, and one year, respectively. Those in