Peptide Library

Growth-hormone secretagogue combination studied for stimulating endogenous GH pulses in research contexts.

Growth Hormone Releasing Peptide-2. Synthetic hexapeptide ghrelin-receptor agonist. Stimulates GH release potently and consistently. Studied since the 1990s; approved in some Asian markets for diagnostic GH stimulation, NOT for therapeutic use in the US.

Synthetic hexapeptide growth-hormone secretagogue developed in the 1990s. Stimulates GH release potently in short-term human studies. Concerns about tachyphylaxis (tolerance) with chronic use have limited clinical development.

Insulin-like Growth Factor 1, Long R3 variant — an analog of human IGF-1 with extended half-life (~20-30 hours vs. ~12 minutes for native IGF-1). Used in research; widely (and controversially) discussed in performance-enhancement communities. NOT FDA-approved for human use; the only approved IGF-1 product is mecasermin (native sequence).

Protein that binds and inhibits members of the TGF-β superfamily, most notably myostatin. Myostatin inhibition increases muscle mass in animals and in rare human genetic conditions (myostatin-deficient individuals). Heavy biohacking / bodybuilding interest. Limited human-trial data for any indication.

Splice variant of IGF-1 (specifically IGF-1Ec) produced locally in muscle in response to mechanical loading. Theorized to drive satellite-cell activation and muscle hypertrophy. Heavy bodybuilding-community interest. Limited human clinical-trial evidence. NOT FDA-approved.