Human experiments

CJC-1295 research in healthy volunteers

The move from GHRH-deficient mice to healthy volunteers changes the question. The clearest human results concern blood hormones and the persistence of a drug signal.

Read the safety concerns Open the reference list

The first human hormone results

The 2006 study by Teichman and colleagues involved healthy adults aged 21 to 61. Single subcutaneous administrations of 30 or 60 micrograms per kilogram produced dose-dependent changes: mean growth hormone rose 2- to 10-fold for 6 days or more, and IGF-1 rose 1.5- to 3-fold for 9-11 days. After multiple administrations, IGF-1 remained above baseline up to 28 days. Estimated CJC-1295 half-life was 5.8-8.1 days.

I credit the long-acting design with a successful pharmacology experiment here. The numbers describe hormone exposure in healthy volunteers. Strength, exercise recovery and the experience of aging require other measurements, collected over a much longer clinical record than this one provides.

Subcutaneous means beneath the skin. Those administrations took place as part of a study; the study-amounts page preserves the context of the figures.

Illustration of two technicians sorting a rack of sealed blood samples beside a centrifuge — An imagined sample-processing room. The human studies followed blood hormones and drug persistence; this illustration depicts no particular laboratory or study visit.

The pulses persisted

Ionescu and Frohman studied healthy men aged 20 to 40 after a single subcutaneous administration of 60 or 90 micrograms per kilogram. One week later, basal growth hormone was approximately 7.5-fold higher, mean growth hormone was about 46 percent higher, and IGF-1 was about 45 percent higher. The frequency and magnitude of the growth hormone pulses were unaltered.

Before this paper, I pictured a long-lived stimulus as something that might flatten the bursts into a steady output. The result corrected that assumption. The gland continued to release growth hormone in pulses, with higher basal levels between them. Duration and release pattern proved to be separate features of the response.

Mean growth hormone about 46 percent higher and IGF-1 about 45 percent higher one week later in healthy men — Healthy men in Ionescu and Frohman’s study: changes in mean growth hormone and IGF-1 one week later. The size and frequency of growth hormone pulses were unaltered.

Serum protein measurements

In 11 healthy young adult men, researchers also examined the serum proteome, the assortment of proteins in the liquid part of blood. Apolipoprotein A1 and a transthyretin isoform decreased; an albumin fragment and immunoglobulin/beta-hemoglobin species increased. The immunoglobulin and albumin-fragment signal correlated with IGF-1.

The serum-protein changes interest me as candidate markers of GH/IGF-1 activity. The study expands the measured response beyond the headline hormones, while the clinical meaning of those protein changes remains unresolved.

The discontinued patient trial

A later Phase 2 trial in people with HIV-associated visceral obesity was discontinued, and development of the long-acting drug ended. A patient death during the development era is often mentioned alongside that history. The public record does not establish that CJC-1295 caused the death.

The halted programme leaves me with unresolved questions about both efficacy and safety. It leaves the human record without the large efficacy and long-term safety trials needed to judge benefits in healthy adults. CJC-1295 remains unapproved for human use. The specific concerns about fluid retention, blood sugar, IGF-1 and immune reactions appear on the safety page.