Sermorelin

Sermorelin (also known as GRF 1-29 or GHRH 1-29) is a synthetic peptide consisting of the first 29 amino acids of human growth hormone-releasing hormone (GHRH). It was one of the first GHRH analogs to be developed and clinically used, representing the shortest fragment of GHRH that retains full biological activity at the GHRH receptor.

Sermorelin works by stimulating the pituitary gland to produce and release endogenous growth hormone (GH), rather than replacing GH directly. This mechanism preserves the body's natural pulsatile GH secretion pattern and feedback regulation. Sermorelin was previously FDA-approved (under the brand name Geref) for diagnosing and treating growth hormone deficiency in children but was discontinued from the commercial market in 2008 for business reasons, not safety concerns.

Sermorelin's clinical history spans several decades. It received FDA orphan drug designation in 1988 and subsequent FDA approvals in 1990 (as a diagnostic agent for pituitary function) and 1997 (for treating pediatric growth hormone deficiency under the brand Geref). Clinical studies in children demonstrated that sermorelin effectively stimulated GH secretion and promoted growth.

Since the manufacturer's voluntary withdrawal from the market, sermorelin has continued to be used in off-label adult contexts through compounding pharmacies, primarily in hormone optimization and anti-aging medicine. However, most published clinical data come from pediatric growth hormone deficiency populations, and well-controlled adult studies are limited. Sermorelin is shorter-acting than some newer GHRH analogs like tesamorelin and CJC-1295.