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This scoping review, conducted following PRISMA-ScR guidelines, examines whether GLP-1 receptor agonists (GLP-1 RAs) — including semaglutide, liraglutide, tirzepatide, and retatrutide — may interfere with autologous fat grafting outcomes. The authors note that millions of patients using GLP-1 RAs for weight loss now present to aesthetic surgeons with facial volume loss and soft tissue deflation, conditions commonly treated with fat grafting. The review synthesizes preclinical and clinical evidence on how GLP-1 RA medications affect adipocyte biology, adipose-derived stem cell (ASC) function, and tissue revascularization. The authors identify several theoretical interference points: GLP-1-mediated adipocyte "browning" and thermogenic activation (including UCP1 upregulation), enhanced lipolysis via ATGL and HSL pathways, suppression of white adipogenic differentiation in ASCs favoring beige/thermogenic lineages, and altered angiogenic and inflammatory signaling during the revascularization window critical to graft survival. The authors explicitly acknowledge that no clinical or preclinical studies have directly examined fat graft outcomes in patients receiving these therapies. The review's conclusions are framed as hypothesis-generating, and any clinical considerations offered are described as mechanism-based rather than evidence-based. This limits the paper's direct applicability to patient care.
Aesthetic surgery journal · Jun 2026DOI ↗ Insufficient
TRANSCEND-CKD (NCT05936151) is a double-blind, placebo-controlled Phase 2b mechanistic trial evaluating retatrutide — a triple agonist of the GIP, GLP-1, and glucagon receptors — in adults with overweight or obesity and chronic kidney disease (CKD). The publication describes the trial's rationale, design, and baseline characteristics of the 146 randomized participants (out of 367 screened). Participants had a mean age of 65.1 years, mean BMI of 35.7 kg/m², and mean measured GFR of 49.3 mL/min/1.73 m² (eGFR range 25–75). Roughly 38% had type 2 diabetes. Participants were randomized 1:1 to once-weekly retatrutide (maximum tolerated dose up to 12 mg) or matched placebo. The primary endpoint is change in measured GFR via iohexol clearance at 24 weeks; secondary endpoints include MRI-assessed kidney hemodynamics, volumes, and perirenal/renal sinus fat. The study is explicitly designed as a mechanistic precursor to the larger cardio-kidney outcomes trial TRIUMPH-Outcomes. Because this paper reports only design and baseline data — with no efficacy or safety outcomes yet — no conclusions about retatrutide's effects on kidney function can be drawn from it.
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association · May 2026DOI ↗ InsufficientPreprint
This study analyzed a large, publicly available independent testing dataset of 6,441 samples spanning fourteen peptide compounds sold through largely unregulated gray market channels directly to consumers. Compounds examined included BPC-157, semaglutide, tirzepatide, PT-141, TB-500, thymosin beta-4, and others marketed for purposes such as injury recovery, muscle growth, fat loss, and athletic performance. Researchers applied two quality acceptance frameworks — one approximating standards for 503A compounded medications and a stricter model reflecting FDA-approved drug production standards — to assess purity, measured abundance, and endotoxin burden. The study found that between 41.6% and 71.1% of samples failed to meet basic quality criteria depending on the framework applied, and measurable endotoxin contamination was detected in 15% of samples. Gray market peptides were consistently cheaper than FDA-approved alternatives, though cost differentials varied widely (e.g., 72.8% higher for tirzepatide vs. 3,850% higher for PT-141 when comparing FDA-approved options). The authors concluded that consumer-directed third-party testing improves transparency but captures only a fraction of the full safety profile relevant to patients self-administering injectable compounds. Key limitations include reliance on a secondary dataset not collected under controlled research conditions and the inability to assess many other safety dimensions beyond purity and endotoxin levels.
Unknown journal · Apr 2026DOI ↗ Insufficient
This cross-sectional pilot study examined the direct-to-consumer market for compounded glucagon-like peptide-1 (GLP-1) receptor agonists in Colorado. Researchers conducted Google searches of business websites advertising compounded GLP-1 products for weight loss across census-defined statistical areas between March and April 2024. They identified 93 websites corresponding to 188 physical locations. Most businesses were categorized as medical/health spas or weight loss services. Semaglutide was the most commonly advertised product (92/93 sites), followed by tirzepatide (40/93). Some sites advertised combination formulations including B vitamins, BPC-157 (flagged by the FDA as unsafe for compounding), and other additives. Seven sites advertised oral formulations. Notably, 41 of 93 websites referenced FDA approval in their product descriptions—a potentially misleading claim, as compounded products are not FDA-approved—and 5 sites incorrectly referred to products as "generic." The study's limitations include its focus on a single state, reliance on publicly available website data, and its pilot/cross-sectional design, which limits generalizability. The authors conclude that regulatory action is needed to address misleading advertising and safety concerns in this market.
Journal of pharmaceutical policy and practice · Dec 2024DOI ↗