CJC-1295 with DAC side effects and safety context

The commonest problems in the published human studies were local and immediate: injection-site irritation, erythema, induration, pain or itching in roughly 70% of dosed subjects in the first study and in all dosed subjects in the second, plus headache in up to 63% versus 14% on placebo, and flushing that was dose-dependent — 40% after a low dose, 100% after a high one (FDA briefing document, PCAC December 2024). The serious question sits elsewhere: the compound's clinical development ended in 2006 after a death in a phase 2 trial, and the data from that trial were never published.

Teichman and colleagues reported no serious adverse reactions across their two ascending-dose studies (J Clin Endocrinol Metab 2006). FDA's reviewers later itemised what was reported, and the itemised list is more informative than the headline:

• Injection-site reactions in ~70% of subjects in study 1 and in 100% of dosed subjects in study 2; more severe and more prolonged at higher doses. Transient urticarial rashes at the site occurred in almost 30% and were not dose-related.

• Headache — 63% versus 14% on placebo in study 1; 20–80% across dose groups in study 2 (with 50% on placebo).

• Gastrointestinal — diarrhoea in 43% of dosed subjects in study 1, rising to 45% and 100% in the 125 and 250 mcg/kg groups.

• Vasodilatory effects — flushing, warmth and transient hypotension in 30% of dosed subjects, typically within 30 minutes of injection and resolving in one to two hours.

• Isolated neurological events — one subject had transient involuntary leg muscle contractions and loss of coordination after a second 30 mcg/kg injection; two had transient dizziness and hypotension after a first dose.

The authors reported no consistent changes in blood or urine laboratory values, including glucose and liver function, or in ECGs.

ConjuChem was running a phase 2 study of CJC-1295 (referred to in reports as DAC:GRF) in people with HIV-associated lipodystrophy — weekly injections in escalating low-dose (60/90/120 mcg/kg) or high-dose (60/120/240 mcg/kg) arms, or placebo, continuing for a further nine weeks. Two hours after an eleventh weekly dose, one participant reported chest discomfort; an ECG confirmed acute myocardial infarction and the participant died approximately an hour later. The attending physician's stated most likely explanation was asymptomatic coronary artery disease with plaque rupture. The study was terminated and its data were never published (FDA briefing document, PCAC December 2024; registry entry NCT00267527, terminated).

Read this carefully in both directions. A single event in a population with known cardiovascular risk cannot establish that the drug caused it, and the attending clinician did not attribute it to the drug. But the trial that would have provided the only multi-week safety dataset in patients was stopped, so nothing about longer exposure entered the literature. The absence of published harm here is the absence of published anything.

FDA's reviewers concluded that the nonclinical studies "suggest that CJC-1295 DAC (free base), CJC-1295 DAC acetate, and CJC-1295 DAC TFA may pose safety risks," and named three specific findings:

• Local injection-site injury — haemorrhage, inflammation and necrosis, consistently observed in rats and dogs given repeated daily subcutaneous injections at doses of 0.25 mg/kg or more for up to 14 days.

• Genotoxic signals — generated both in vitro, in primary cultures of mouse pituitary cells, and in vivo.

• No carcinogenicity data at all. No two-year study exists. Because transgenic mice overexpressing human GHRH develop pituitary hyperplasia and tumours, FDA judged that the potential for the same to occur with long-term dosing "cannot be ruled out."

In December 2024 the Pharmacy Compounding Advisory Committee voted 13–0 that CJC-1295 DAC should not be placed on the 503A list of substances usable in compounded medicines, and 13–0 the same way on every other CJC-1295 form put to it (PCAC final summary minutes, 4 December 2024).

Anything that reliably raises GH and IGF-1 inherits the warnings on approved growth hormone labels, and FDA said as much: it "has not identified data or information to suggest" that CJC-1295 forms would not present similar risks — increased risk of neoplasm, glucose intolerance and diabetes, intracranial hypertension, fluid retention, hypoadrenalism, hypothyroidism and pancreatitis.

A class review of growth hormone secretagogues found them generally well tolerated in short studies but singled out rises in blood glucose driven by falling insulin sensitivity, and called explicitly for evaluation of cancer incidence and mortality with long-term use (Sigalos & Pastuszak, Sex Med Rev 2018). The DAC form is the version of this class least able to be backed out of quickly: with a half-life of roughly six to eight days, a dose that turns out to be a problem stays in the system for over a week.

For what the compound is claimed to do, see CJC-1295 with DAC benefits; for the numbers people actually use, see dosing education.