Sometimes incorrectly referred to as CJC-1293 or CJC-1295 without DAC, Modified GRF (1-29) is different from any “CJC” peptide in that it lacks a lysine conjugate and it is not a drug affinity complex (DAC for short). DACs are a class of peptide analog that are bound by a lysine link to a reactive chemical called maleimidoproprionic acid (MPA). (Teichman et al, 2006) In vivo MPA binds almost exclusively to albumin, and the active life of the bound peptide becomes equal to the circulating life of albumin; in human plasma, this is approximately ten days. CJC-1293 is a single-substituted 29-amino analog of GHRH bound to MPA, making it a DAC. CJC-1295 is a tetrasubstituted 29-amino analog of GHRH bound to MPA, also making it a DAC.
"The core therapeutic moiety is GHRH-(1–29)NH2, which contains the full biological activity of GHRH-(1–44)NH2 modified by substitution of four amino acids that serve to render the compound more resistant to proteolytic cleavage (herein called GRF). GRF is linked by the amino acid, lysine, to a reactive chemical …. At least 90% of CJC-1295 binds covalently to albumin in this fashion…extend[ing] the half-life of the active pharmacophore, resulting in a markedly prolonged duration of action. (Teichman et al, 2006)"
ModGRF (1-29) is not CJC-1295 or CJC-1293 nor should it be referred to as “CJC-1295 without DAC. Modified GRF (1-29) is identical to the portion of CJC-1295 that is not bound to MPA, minus the lysine. The presence of lysine in a literal “CJC without DAC” in the absence of MPA would have the opposite effect of DAC: it would drastically reduce the active life of the peptide to that of sermorelin.
"The core therapeutic moiety is GHRH-(1–29)NH2, which contains the full biological activity of GHRH-(1–44)NH2 modified by substitution of four amino acids that serve to render the compound more resistant to proteolytic cleavage (herein called GRF). GRF is linked by the amino acid, lysine, to a reactive chemical …. At least 90% of CJC-1295 binds covalently to albumin in this fashion…extend[ing] the half-life of the active pharmacophore, resulting in a markedly prolonged duration of action. (Teichman et al, 2006)"
ModGRF (1-29) is not CJC-1295 or CJC-1293 nor should it be referred to as “CJC-1295 without DAC. Modified GRF (1-29) is identical to the portion of CJC-1295 that is not bound to MPA, minus the lysine. The presence of lysine in a literal “CJC without DAC” in the absence of MPA would have the opposite effect of DAC: it would drastically reduce the active life of the peptide to that of sermorelin.
