Sermorelin

Sermorelin - Original GHRH (1-29) Analog

Sermorelin is a synthetic 29-amino-acid peptide corresponding to the active N-terminal fragment of human GHRH (Growth Hormone Releasing Hormone). It was one of the earliest GHRH analogs developed and was briefly marketed as Geref for pediatric GH deficiency before being discontinued commercially. In the peptide-research toolkit it sits as the “reference GHRH” - the baseline unmodified analog that newer GHRH peptides (CJC-1295 No DAC, Tesamorelin) are benchmarked against.

Why GHRH (1-29) Matters

The native GHRH hormone is 44 amino acids long, but the GH-releasing activity is concentrated in the first 29 residues. Sermorelin is that fragment, unmodified. It binds the pituitary GHRH receptor and triggers a short, physiologically-shaped GH pulse, but is degraded within minutes by the DPP-4 enzyme. That short half-life is useful for studies that want unmodified GHRH pharmacokinetics, but is also why later analogs (CJC-1295 No DAC adds four DPP-4-resistant substitutions; Tesamorelin adds a stabilizing N-terminal group) were developed.

Sermorelin vs CJC-1295 No DAC vs Tesamorelin

All three are GHRH analogs that hit the same receptor; they differ in how long they stay active in circulation.

Research Applications

Sermorelin is used in studies examining:

• Baseline GHRH-receptor characterization
• Pulsatile GH release modeling
• IGF-1 dose-response under unmodified GHRH
• Paired GHRH + GHRP studies (typically with Ipamorelin)
• Comparative pharmacokinetics vs. stabilized analogs

Specifications

Storage & Handling

Unopened vials are kept at 2-8°C under standard cold-chain conditions and remain stable for 12+ months. Reconstitution parameters, solvent compatibility, and post-reconstitution stability for Sermorelin are documented in the published peer-reviewed literature and standard peptide-chemistry references.

Reference Literature

Published clinical and preclinical Sermorelin literature is available through PubMed, Google Scholar, and other peer-reviewed databases. WWP does not provide protocol design, dosing guidance, or administration parameters. Those decisions rest with the researcher and any applicable institutional review board.

Common Questions About Sermorelin Research

What does Sermorelin do in research?

It activates the pituitary GHRH receptor and triggers a short pulse of GH release. Downstream, GH converts to IGF-1 in the liver, which is the primary biomarker tracked in most studies. Sermorelin’s short half-life preserves the natural pulsatile pattern of GH release.

How does Sermorelin compare to Ipamorelin?

They act through different receptors. Sermorelin is a GHRH analog (initiates the GH pulse). Ipamorelin is a GHRP (amplifies the pulse via the ghrelin receptor). They are not interchangeable - researchers often pair them because the two pathways work together.

How does Sermorelin compare to CJC-1295?

They hit the same receptor but have different half-lives. Sermorelin is the unmodified GHRH (1-29) fragment, degraded by DPP-4 within minutes. CJC-1295 No DAC adds four DPP-4-resistant substitutions that roughly 2-3x the half-life. CJC-1295 with DAC adds an albumin-binding adapter that extends the half-life to about a week.

Is Sermorelin FDA approved?

Sermorelin was previously approved (as Geref) for pediatric GH deficiency but has since been discontinued in the US market. It is not currently available as an approved drug. Every vial WWP ships is labeled and sold strictly for laboratory and research use only.

How is Sermorelin stored?

Unopened vials are stored at 2-8°C and stay stable for 12+ months. Once reconstituted with bacteriostatic water, the solution is kept at 2-8°C and used within 28-30 days.

Purity Guarantee

Every batch is ≥99% purity. Send us a COA from any independent test and we’ll issue store credit regardless of what it shows.