The Cold Open
Sermorelin is unusual. Unlike most peptides in this newsletter, it was actually FDA-approved. It had a brand name (Geref) and real labeling. Then, quietly, it left the US market. The FDA has explicitly stated Geref was not withdrawn for safety or efficacy reasons. So why is a clinically validated GH-releasing peptide only available today through compounding pharmacies and research-chemical vendors? This month: what Sermorelin does, what the trials show, and the very strange story of a peptide that graduated and then dropped out.
Peptide of the Month: Sermorelin
What it is. Sermorelin is a 29-amino-acid fragment of growth hormone-releasing hormone, or GHRH. Your body makes GHRH naturally in the hypothalamus; it tells the pituitary to release growth hormone. Sermorelin is the working end of that key, synthesized in a lab.
What it's supposedly for. Originally FDA-approved in 1997 for treating growth hormone deficiency in children. Today it's marketed off-label in adult wellness clinics for body composition, better sleep, recovery, and vague "anti-aging" benefits.
The evidence as of today. The pediatric evidence is solid. A 1996 study showed once-daily sermorelin accelerated growth in GH-deficient children. A 1994 study showed partial effects in idiopathic short stature. On the adult side, a 1992 trial found twice-daily dosing raised GH and IGF-1 levels in older men. A 1997 study extended this to older men and women, with measurable endocrine shifts. Those are real effects on lab values. What's missing, even after 30 years, is a trial showing sermorelin improves hard outcomes in healthy adults: less frailty, better body composition long-term, fewer falls, lower mortality. The endocrine numbers move. Whether the life actually improves is still unanswered.
One thing to know: Geref's quiet exit. Geref was the branded sermorelin product. The FDA formally declared it was not withdrawn for safety or effectiveness. It left the market for commercial reasons, probably because synthetic recombinant GH was more profitable. The approval is still on the books.
A peptide with an FDA file, decent pediatric trials, and a commercial life that ended without a scientific verdict.
The catch. The FDA-approved product no longer exists in the US. What you can buy today is compounded sermorelin from wellness clinics, or grey-market research powder. Neither has the quality control the original Geref manufacturing had. Dose, purity, and sterility all vary by supplier.
Research Radar: Where Sermorelin's story stands in 2025
Three developments worth knowing.
No modern Phase III. Despite 30-plus years of adult off-label use, no large randomized trial has tested sermorelin for body composition, frailty, or healthspan in healthy older adults. The evidence base stopped growing when the approved product left the market.
Compounding pharmacies fill the gap. The FDA has issued repeated warnings about compounded peptide products, including concerns about purity, potency variation, and false marketing claims. Sermorelin is frequently named in those warnings.
The GH-axis field moved elsewhere. Modern endocrine research on the GH/IGF-1 axis now focuses on newer secretagogues like tesamorelin (FDA-approved for HIV-associated lipodystrophy) and emerging ghrelin-receptor agonists. Sermorelin has become a legacy molecule.
The rule: "FDA-approved" is not a permanent status. Check whether the approval applies to what you're buying, how it's made, and what indication you're using it for.
Not medical advice. Most peptides discussed in this newsletter are investigational or research chemicals. Talk to a clinician before starting anything.