CJC-1295 (Modified GRF
1-29)

1980s-2000

The Half-Life Problem

Why Peptide Drugs Are Difficult

Growth hormone-releasing hormone (GHRH) is the body's signal to release growth hormone. Scientists had synthesized GHRH, but it was useless as a drug — enzymes destroyed it within minutes of injection.

Daily or even multiple daily injections would be needed to use GHRH therapeutically. This made it impractical compared to simply injecting growth hormone itself. The question was: could GHRH be modified to last longer?

The challenge was formidable. Change the amino acids too much and you lose activity. Don't change enough and enzymes still destroy it. Finding the sweet spot required systematic engineering.

2000-2005

The ConjuChem Solution

DAC Technology

ConjuChem Biotechnologies in Montreal developed a clever approach. They modified GHRH(1-29) with strategic amino acid changes at positions 2, 8, 15, and 27 to resist DPP-4. Then they added something new: a Drug Affinity Complex (DAC).

DAC was a reactive group that attached to albumin — the most abundant protein in blood. Once attached to albumin, the peptide couldn't be filtered out by kidneys and was protected from degradation. It would circulate for days.

The result was CJC-1295. In early tests, a single injection raised growth hormone levels for 6-8 days. This was unprecedented for a peptide hormone.

2005-2008

Clinical Promise

Phase I and II Trials

Clinical trials began in healthy adults and patients with lipodystrophy and growth hormone deficiency. The results were encouraging. CJC-1295 produced sustained increases in growth hormone and IGF-1.

Remarkably, the body's normal pulsatile pattern of GH release was preserved. Continuous GHRH stimulation didn't cause GH levels to flatten — the pituitary still released GH in pulses, just bigger ones. This suggested physiological hormone replacement might be possible.

The drug appeared safe and well-tolerated. ConjuChem moved toward larger trials. The future looked bright.

2008

The Trial Halted

A Subject Death

In 2008, development stopped. A subject in a clinical trial died. While the connection to CJC-1295 was never definitively established, the death triggered safety reviews and halted the program.

ConjuChem faced financial difficulties. The company couldn't continue development. CJC-1295 never reached Phase III trials. The promise of once-weekly growth hormone stimulation remained unfulfilled.

The incident highlighted the risks of clinical drug development. Even promising compounds can fail — sometimes for reasons that are never fully understood.

2008-Present

The Research Legacy

Underground Use and Scientific Value

Though never approved, CJC-1295 became available from research peptide suppliers. Athletes and anti-aging enthusiasts combined it with GHRP peptides like Ipamorelin, seeking synergistic growth hormone release.

Two forms emerged in the market: CJC-1295 with DAC (long-acting) and CJC-1295 without DAC (also called Modified GRF 1-29, shorter-acting). Users debated which was better for physiological versus sustained stimulation.

Scientifically, CJC-1295 proved that peptide hormones could be engineered for long duration. This technology has influenced development of other long-acting peptides. The compound remains important in research, even though it never became a medicine.