Tesamorelin

Tesamorelin 20 mg from PrimeTime BioLabs is a standalone research peptide — it is not a Tesamorelin/Ipamorelin blend, and researchers evaluating this listing should not assume the specifications of a combination product apply here. The material is packaged as a single-use lyophilized vial, sealed and light-protected to preserve peptide integrity in transit, with a lot-specific label that ties the vial directly to its batch documentation. The compound itself is Tesamorelin, a synthetic analogue of the 44-amino-acid human growth hormone-releasing factor (GRF), also called GHRH. What separates Tesamorelin from the native hormone is a single, well-documented structural change: an N-terminal trans-3-hexenoyl group attached to the tyrosine residue at position one. That modification is the defining feature of Tesamorelin as its own chemical entity, and it's the reason Tesamorelin and native GHRH are related compounds rather than identical ones. Exact chemical-identity figures (CAS number, molecular formula, and molecular weight) vary slightly across suppliers depending on which salt or solvated form is reported — free base versus acetate, for example, shift the molecular weight. PrimeTime BioLabs has not published which specific form applies to this listing, so researchers needing a precise reference figure for characterization or database cross-referencing should confirm the form directly against the batch's Certificate of Analysis rather than relying on a general registry value. Each PrimeTime batch carries its own lot number, purity figure, and analysis date on the downloadable Certificate of Analysis rather than a single blanket specification for every vial sold under this listing. The current batch on file is PTBL08312026, tested at 99% purity and analyzed 9/2/2026 — researchers should confirm the lot number on their own vial matches the COA they download, since batch-specific documentation is only meaningful when it's matched to the physical product in hand. Storage guidance, per PrimeTime's own product documentation: keep the lyophilized vial in a freezer at −20°C, protected from light, until ready for use. Once reconstituted, refrigerate at 2–8°C and use within the window noted on the batch's Certificate of Analysis. This is a research-material handling recommendation, not a personal-use or administration instruction.

Growth hormone-releasing hormone is one of the body's core signals for pituitary function. Produced in the hypothalamus, GHRH acts on receptors located on somatotroph cells in the anterior pituitary, prompting the pulsatile synthesis and release of endogenous growth hormone. That GH release, in turn, drives downstream production of IGF-1, primarily in the liver, which mediates many of GH's longer-term physiological effects. Tesamorelin was developed as a stabilized GHRH/GRF analogue rather than a copy of the native hormone. The trans-3-hexenoyl modification at the N-terminal tyrosine changes the compound's stability profile relative to unmodified GHRH, which is one reason it's studied separately from the native peptide rather than treated as interchangeable with it. Research on Tesamorelin's receptor pharmacology describes binding and stimulation of the human GRF receptor with potency comparable to endogenous GRF — that's evidence about the molecule's interaction with its target, not evidence about a specific outcome in any particular research application. It's worth being precise about what Tesamorelin is not. It is not growth hormone itself — GH is the pituitary hormone released downstream of GHRH-receptor activation, while Tesamorelin is the upstream signaling analogue. It is not IGF-1 — IGF-1 is a separate growth factor produced further down the same signaling cascade. And it is not automatically interchangeable with a Tesamorelin/Ipamorelin combination product; those are distinct formulations studied under different research designs. Keeping these distinctions clear matters both for accurate research design and for avoiding confusion with unrelated products. Tesamorelin is also the active compound in FDA-approved prescription products marketed under the Egrifta and Egrifta SV names, indicated for a specific clinical population. Those are separate, regulated drug products with their own formulation, dosing, packaging, and approved labeling. The clinical evidence associated with those prescription products describes the approved drug — it does not describe, and should not be read as describing, the purity, formulation, or research performance of PrimeTime's Tesamorelin 20 mg material. Evidence about the compound's biology exists at several levels — in-vitro receptor studies, animal pharmacology, and controlled human trials tied to the approved drug — and each of those describes a different kind of finding. None of it substitutes for lot-specific analytical testing of a given research batch, which is what the Certificate of Analysis is for.

PrimeTime BioLabs states that each lot of Tesamorelin 20 mg is third-party tested for purity and identity, with a matching Certificate of Analysis available for download so researchers can confirm the specifications of the exact batch they receive. The current COA on file for this listing reports batch PTBL08312026 at 99% purity, analyzed 9/2/2026. It helps to be precise about what that kind of testing actually establishes. A purity figure derived from chromatographic analysis describes the proportion of the tested sample that corresponds to the target compound under that specific method — it's a statement about analytical composition, not a statement about biological activity, sterility, or suitability for any particular use. Identity testing, separately, supports the conclusion that the material tested is consistent with the expected molecular structure; it doesn't by itself confirm potency or purity. Neither of these is a substitute for the other, and neither one is a claim about efficacy. That distinction matters for how researchers should read a Certificate of Analysis: a COA connects a specific lot number, testing date, and analytical result to a specific batch of material. It is documentation of what was measured in that batch, on that date, by that method — not a general guarantee that extends to every future shipment or every possible use case. Matching the lot number on a physical vial to the lot number on its COA is the step that makes the documentation useful; a COA that doesn't correspond to the vial in hand doesn't tell a researcher anything about that vial. PrimeTime's testing framework focuses on the two figures most relevant to research-material evaluation — purity and identity — figures a researcher can use in study design and record-keeping. Any additional test parameters, if and when they're added to a batch's documentation, will appear on that lot's Certificate of Analysis rather than as a general page-wide claim.

Tesamorelin 20 mg is distributed exclusively for qualified research purposes. It carries no FDA approval, is not intended for human or animal consumption, and must be handled only by trained laboratory personnel operating in a controlled research setting. This product is not a drug, dietary supplement, or cosmetic. It is not intended for diagnostic or therapeutic use of any kind, and PrimeTime BioLabs makes no representation that it is equivalent to, or interchangeable with, any FDA-approved prescription drug product, including Egrifta or Egrifta SV. This listing does not provide dosing or administration instructions for human or animal use, and none should be inferred from the product description, mechanism overview, or documentation on this page. Any reconstitution or storage information provided elsewhere on this page is a laboratory handling recommendation only, not guidance for personal or clinical administration. Researchers are responsible for ensuring their use of this material complies with applicable institutional, state, and federal regulations governing research-use-only compounds.