Growth hormone results across four research records
A height measurement, a blood sample, a meal after surgery and a cell signal. The same broad hormonal interest leads to very different experiments.
Measured outcomes
The most useful comparison starts with the destination of each experiment. Putting the destination first helps me resist a misleading similarity between the records.
| Study | Participants or model | Main finding |
|---|---|---|
| Ipamorelin after bowel surgery | 114 adults after bowel resection | The primary endpoint, time to a tolerated meal, was not met. |
| Ipamorelin exposure | Healthy male volunteers | A discrete growth hormone peak at about 40 minutes; approximately 2-hour peptide half-life. |
| CJC-1295 serum proteins | 11 healthy young men | Several protein species shifted; some signals correlated with IGF-1. |
| Sermorelin and height | Prepubertal children with growth hormone deficiency | First-year height velocity rose from about 4.1 to roughly 7–8 centimeters per year. |
| Dual-receptor activation | Engineered HeLa cells | Approximately twice the intracellular cAMP response; no fixed-pair human treatment result. |
Receptors and duration
Sermorelin and CJC-1295 act at the GHRH receptor. Ipamorelin acts at the ghrelin receptor. The GHRH review describes how these related signals fit into growth hormone release.
Sermorelin’s short sequence breaks down within minutes. Ipamorelin’s human intravenous study found a roughly 2-hour terminal half-life. CJC-1295 with DAC binds albumin; its human hormone effects persisted for days. No-DAC Modified GRF (1–29) lacks that attachment and has a roughly 30-minute half-life.
Comparisons frustrate me when they call one compound stronger while leaving out the CJC form, the measurement and the elapsed time. A short peptide exposure, a prolonged IGF-1 rise and a child’s annual growth rate describe different quantities. The fixed CJC-1295/ipamorelin combination has no human exposure study that would unify them.
Clinical claims and approval
The direct sermorelin height result concerned a hormone deficiency in children. Its former FDA approval concerned that paediatric use; the medicine left the market in 2008 for commercial reasons. Compounded sermorelin remains unapproved and subject to the conditions of FDA’s Category 1 interim 503A policy.
Ipamorelin and CJC-1295 have never had drug approval. The withdrawal of their compounding nominations, listed on FDA’s page current as of April 22, 2026, grants no clearance. All four substances or combinations are prohibited in sport.
The proposed pair also borrows attention from tesamorelin fat-loss trials in HIV-associated lipodystrophy. Those trials have their own drug and patient population. A fair comparison leaves them visible rather than quietly relabelling them as combination results.
I’d put a meaningful outcome alongside glucose, swelling and other harms in the next trial. The safety review’s call for longer follow-up makes particular sense when exposure lasts much longer than the moment of an injection.