Source comparison
Modified GRF (1-29) vs CJC-1295 with DAC
Here's the honest answer: most commercially available CJC-1295 is actually Modified GRF (1-29), a peptide that shares the same 29-amino-acid sequence but lacks the DAC modification. The pharmacokinetic profile is not comparable. Modified GRF (1-29) has a half-
This comparison does not assign a generated winner or score.
- Here's the honest answer: most commercially available CJC-1295 is actually Modified GRF (1-29), a peptide that shares the same 29-amino-acid sequence but lacks the DAC modification. The pharmacokinetic profile is not comparable. Modified GRF (1-29) has a half-life of approximately 30 minutes, meaning it must be dosed multiple times daily to maintain any sustained effect. Typically 100–200 mcg three times per day. The CJC-1295 study results demonstrating 6–13 days of elevated IGF-1 do not apply to this compound.
- The DAC modification in true CJC-1295 involves conjugating the peptide to a maleimidoproprionic acid (MPA) moiety, which binds non-covalently to endogenous serum albumin. This albumin binding shields the peptide from proteolytic enzymes (primarily dipeptidyl peptidase-IV) that would otherwise cleave and inactivate it within minutes. Modified GRF (1-29) lacks this modification entirely. It is rapidly degraded, producing a short but potent GH pulse rather than sustained secretion.
- Why the naming confusion? Modified GRF (1-29) was developed as a research tool to mimic the pulsatile GH secretion pattern observed in natural physiology, while CJC-1295 with DAC was designed for therapeutic applications requiring steady-state GH elevation. Both are valuable. But they serve different experimental purposes, and the CJC-1295 study data applies only to the DAC-modified version. Researchers sourcing peptides should verify which form they're receiving, as the labeling is often inconsistent across suppliers. Our commitment to quality extends across our full peptide collection, where every compound is synthesized with exact amino-acid sequencing and verified for structural integrity.