Tesamorelin and CJC-1295 are the same idea executed twice: take growth hormone-releasing hormone, which the body breaks down in minutes, and modify it so it survives long enough to be a drug. Both hit the GHRH receptor on the pituitary. Both raise growth hormone and IGF-1. From there their histories diverge completely, which is what makes this the cleanest approved-versus-unapproved pairing in the whole GH-axis peptide family.
Tesamorelin went through phase 3 trials, got an FDA label in 2010, and is still sold under it. CJC-1295 was withdrawn from development in 2006 after a trial participant died, was never published in a patient population, and in December 2024 was rejected unanimously by FDA's advisory committee for pharmacy compounding. What follows is not about which one works better, but about the difference between a compound whose limits have been measured and one whose limits are unknown.
Head-to-head
| Dimension | Tesamorelin | CJC-1295 |
|---|---|---|
| Molecule & modification | The full 44-amino-acid human growth hormone-releasing factor sequence with a hexenoyl group (C6 chain, double bond at position 3) on the N-terminal tyrosine; 5,135.9 Da as free base. | A 29-amino-acid GHRH(1-29) analog with substitutions at positions 2, 8, 15 and 27, sold either as-is (3,367.95 g/mol) or with a maleimidopropionamide-lysine “drug affinity complex” at the C-terminus. |
| Receptor | GHRH receptor on pituitary somatotrophs; raises endogenous GH and, downstream, IGF-1. | The same GHRH receptor. The DAC forms are documented GH secretagogues in rodents; FDA found no studies establishing that the non-DAC free base is even pharmacologically active. |
| Half-life | 8 minutes in healthy subjects after a single 1.4 mg subcutaneous dose (EGRIFTA SV label). | DAC forms: 5.8–8.1 days in healthy adults. Non-DAC: never measured in a person. That is minutes versus a week across products sharing one name. |
| Approval status | FDA-approved since 2010. Currently marketed as EGRIFTA SV and EGRIFTA WR for one indication: reduction of excess abdominal fat in HIV-infected adults with lipodystrophy. | Never approved in any jurisdiction. Development stopped in 2006. Not on FDA’s 503A bulks list for compounding. |
| Human trial evidence | Two phase 3 RCTs, pooled n = 806 (543 drug, 263 placebo), plus a 404-patient trial with re-randomization and a 61-patient liver-fat RCT. Endpoints imaged, not self-reported. | Ascending-dose safety/PK studies in 63 healthy adults across three reports. The one phase 2 trial in a patient population was terminated and never published. |
| What the visceral-fat data shows | VAT fell 24 ± 41 cm² vs a 2 ± 35 cm² rise on placebo at week 26 (−15.4% treatment effect), reaching −17.5% at week 52 in continuers. Patients switched to placebo rapidly lost the gain; body weight is unchanged either way. | No visceral-fat outcome has ever been published. The one trial designed to measure it ended early. |
| Identity reliability | One defined active ingredient with a structural formula in the prescribing information, made under FDA manufacturing oversight. | FDA evaluated five chemically distinct CJC-1295-related bulk substances and could not determine which one the published human studies used. A vial labelled “CJC-1295” does not tell you what is in it. |
| Anti-doping | Prohibited at all times. GHRH and its synthetic analogs sit in WADA class S2; tesamorelin is a named target in doping-control assay development. | Prohibited at all times under the same S2 heading, and identified by mass spectrometry in a seized preparation as early as 2009. |
Same receptor, opposite engineering choices
Tesamorelin keeps the whole 44-amino-acid GHRH sequence and defends it from the outside: a hexenoyl moiety — a six-carbon chain with a double bond at position 3 — is attached to the N-terminal tyrosine, and the molecule weighs 5,135.9 Da as free base (EGRIFTA SV prescribing information, DailyMed). It is still fast: mean elimination half-life is 8 minutes in healthy subjects. The engineering bought stability, not duration, and the product is dosed once daily.
CJC-1295 took the opposite route. It shortens the peptide to GHRH(1-29) and swaps four residues for chemical reasons — D-alanine at position 2 to resist dipeptidyl peptidase-IV, glutamine at 8 to avoid asparagine rearrangement, leucine at 27 to avoid methionine oxidation — then adds a maleimido-lysine that reacts in the bloodstream with the free thiol on cysteine-34 of serum albumin, so the peptide travels with albumin instead of being cleared. In rats that conjugate produced a four-fold larger GH area under the curve than unmodified hGRF(1-29) and remained in plasma beyond 72 hours (Jetté et al., Endocrinology 2005). In healthy adults, single injections raised GH two- to ten-fold for six days or more and IGF-1 1.5- to three-fold for 9–11 days, with an estimated half-life of 5.8–8.1 days (Teichman et al., J Clin Endocrinol Metab 2006). That is the entire published human pharmacology.
What the visceral-fat data actually shows
The pooled analysis of two multicentre, double-blind phase 3 trials covered 806 antiretroviral-treated adults with HIV and excess abdominal fat, 543 on tesamorelin and 263 on placebo. At week 26, visceral adipose tissue fell 24 ± 41 cm² on drug against a 2 ± 35 cm² increase on placebo — a −15.4% treatment effect — and continuers reached −35 ± 50 cm², or −17.5%, by week 52 (Falutz et al., J Clin Endocrinol Metab 2010). Those are real numbers from CT imaging, and they are also modest ones.
The detail wellness marketing leaves out is what happened in the second half of the 404-patient trial. Participants who had responded over six months were re-randomized; those switched from tesamorelin to placebo rapidly lost the improvement they had gained, while those who continued reached roughly −18% at twelve months (Falutz et al., J Acquir Immune Defic Syndr 2010). Tesamorelin does not reset visceral fat; it suppresses it for as long as it is being injected. Any framing of it as a course of treatment with a lasting body-composition result contradicts its own phase 3 extension.
Two further findings shape how the effect should be read. A responder analysis of 402 tesamorelin-randomized subjects defined response as ≥8% VAT reduction at 26 weeks and found the metabolic benefits tracked the fat loss rather than the drug: responders improved triglycerides by 0.6 mmol/L versus 0.1 in non-responders (P = .005) and had smaller rises in fasting glucose and HbA1c (Stanley et al., Clin Infect Dis 2012). And in a separate 61-person randomized trial, twelve months of tesamorelin cut hepatic fat fraction by 4.1 absolute percentage points relative to placebo, a 37% relative reduction, with 35% of the treated group versus 4% of placebo dropping below the 5% steatosis threshold (Stanley et al., Lancet HIV 2019).
The label is blunter than any of this. It states that tesamorelin is not indicated for weight loss management, having a weight-neutral effect, that long-term cardiovascular safety has not been established, and that continuation should be reconsidered in patients whose visceral fat has not fallen. It is contraindicated in active malignancy, in disruption of the hypothalamic-pituitary axis, and in pregnancy; IGF-1 must be monitored; and 5% of treated patients reached an HbA1c of 6.5% or higher versus 1% on placebo, hazard ratio 3.3 (CI 1.4, 9.6). Growth hormone opposes insulin, so that last one is mechanism, not accident.
The dose everyone quotes was retired
“Tesamorelin 2 mg daily” is the figure in almost every secondary write-up. It belongs to the original phase 3 programme and the discontinued first-generation product. The two currently marketed presentations are EGRIFTA SV at 1.4 mg once daily (0.35 mL of the reconstituted 2 mg vial) and EGRIFTA WR at 1.28 mg once daily (0.16 mL of a weekly-reconstituted vial). The 1.4 mg dose is not a reduction in exposure — the label notes Cmax and AUC are similar to the old 2 mg dose — it is a different formulation. The labels state plainly that the two products differ in dosage, vials per dose, reconstitution and storage, and that EGRIFTA WR and EGRIFTA SV are not substitutable (EGRIFTA WR prescribing information, DailyMed). A dose quoted without its formulation is exactly what that wording exists to prevent.
CJC-1295's development ended with a death
ConjuChem ran a phase 2 study of CJC-1295 (referred to in reports as DAC:GRF) in HIV-associated visceral obesity — the same clinical problem tesamorelin was approved for. The registry entry lists it as phase 2, enrolment 120, started December 2005, and terminated in September 2006 (NCT00267527). FDA's account of the reported trial describes 192 subjects randomized to escalating weekly doses or placebo; two hours after an eleventh weekly dose, one participant reported chest discomfort, an ECG confirmed acute myocardial infarction, and he died about an hour later. The attending physician's most likely explanation was asymptomatic coronary artery disease with plaque rupture. The study was terminated and its data never published (FDA briefing document, PCAC 4 December 2024).
One death does not establish causation, and the physician offered a non-drug explanation. The consequence is what matters here: the only study that would have produced patient outcome data for CJC-1295 stopped, so the compound has no efficacy result in anyone with a condition. FDA's 2024 review adds the unfinished safety work — injection-site hemorrhage, inflammation and necrosis in rats and dogs at repeated daily doses; genotoxic signals in mouse pituitary cells in vitro and in vivo; and no two-year carcinogenicity studies for any of the five substances, which the agency flags against the background that transgenic mice overexpressing human GHRH develop pituitary hyperplasia and tumours.
“CJC-1295” does not name a single molecule
This is the failure mode with no counterpart on the tesamorelin side. FDA evaluated five chemically distinct CJC-1295-related bulk substances — CJC-1295 (free base), CJC-1295 acetate, CJC-1295 DAC (free base), CJC-1295 DAC acetate and CJC-1295 DAC trifluoroacetate — concluded they are not well characterized, and stated that even in the published human studies “it is unclear which substance was used.” It also concluded that the DAC version's pharmacology cannot be extrapolated to the version without the DAC modification.
Put the pharmacokinetics next to each other and the problem is obvious. The DAC forms have a measured half-life of roughly 5.4–9.2 days. The non-DAC free base has never had one published; its unmodified parent, sermorelin (GHRH 1-29), has a plasma half-life of about 10–20 minutes in humans (Esposito et al., Adv Drug Deliv Rev 2003). Two vials can carry the same three-character label and differ in duration of action by something close to three orders of magnitude. Tesamorelin, by contrast, has one active ingredient with a printed structural formula and a manufacturer answerable for what is in the vial. That difference is not about potency — it is about whether the word on the label corresponds to a known quantity.
What FDA's advisory committee did with it
On 4 December 2024 the Pharmacy Compounding Advisory Committee voted on whether CJC-1295 substances should be added to the 503A bulks list, which governs what compounding pharmacies may legally use. The results were 0 yes / 13 no for CJC-1295 free base, and the same 0–13 for CJC-1295 DAC free base, DAC acetate and DAC trifluoroacetate; CJC-1295 acetate went 1–12. The minutes record that the committee “unanimously agreed” the free base should not be included (PCAC final summary minutes, 4 December 2024). A clinic advertising compounded CJC-1295 is therefore not operating in a grey area that regulators have not looked at; it is operating past a review that examined the compound in detail and declined it.
Both are prohibited in sport
The regulatory gap closes here. Growth hormone-releasing hormone and its synthetic analogs are prohibited by WADA at all times under class S2, and anti-doping laboratories have built assays covering sermorelin, tesamorelin, CJC-1295 and CJC-1295 DAC together — one 2021 method identified 19 urinary metabolites and reached detection limits of 1 ng/mL or better (Memdouh et al., Drug Test Anal 2021). CJC-1295 entered that literature by an unusual door: its first scientific appearance was a Norwegian doping-control laboratory identifying it by high-resolution mass spectrometry in an unknown seized preparation, already noting its prohibited status (Henninge et al., Drug Test Anal 2010). Holding an FDA approval does not exempt tesamorelin: a tested athlete faces the same S2 finding either way.
Why the two get sold as interchangeable
The conflation works because the shared premise is true: both are GHRH analogs, both raise GH and IGF-1, and tesamorelin has a headline visceral-fat result. Marketing borrows that result, drops the population it came from, drops the reversal on discontinuation, drops the label sentence saying the drug is weight neutral, and attaches what is left to a peptide with no patient trial at all. Four questions separate the two: which population, what happened after stopping, which specific molecule, and who was answerable for the vial.
If the interest is the GHRH pathway itself, note that the two other members of this family in wide circulation resolve differently again. Sermorelin is the one GHRH analog that held an approval for treating GH deficiency and then left the market for commercial rather than safety reasons, as its Drugs@FDA record and the Federal Register determination behind it show; CJC-1295 without DAC is sold under a second name, modified GRF 1-29, for the same molecule. The CJC-1295 vs sermorelin comparison covers that pair.
Dive deeper
- Tesamorelin overview · benefits · side effects · dosing concepts · research
- CJC-1295 with DAC overview · side effects · research
- CJC-1295 without DAC overview · dosing concepts · research
- Related molecules: Sermorelin acetate · Ipamorelin · CJC-1295 + Ipamorelin blend
- Related comparisons: CJC-1295 vs sermorelin · all comparisons
- General context: can you regain weight after stopping peptides · what are the risks of peptides · why some doctors do not prescribe peptides · who should avoid using peptides
This page is educational and non-prescriptive. It summarizes published trial results, prescribing information and regulatory records for two GHRH analogs, and does not recommend, or advise against, using either.