What are growth hormone peptides like sermorelin and ipamorelin?

What they are

Sermorelin, tesamorelin, CJC-1295, ipamorelin and ibutamoren (MK-677) make the pituitary, a gland at the base of the brain, release more of the body’s own growth hormone. All but ibutamoren are amino acid chains: tesamorelin, with 44, counts as a protein under FDA rules, the others as peptides. AOD-9604, also a peptide, is a fragment of growth hormone itself.^{7,1,2,4,3,5,27}

The hypothalamus, a brain region above the pituitary, triggers growth hormone release in pulses with growth hormone-releasing hormone (GHRH). Ghrelin, a stomach hormone, signals through its own receptor, a docking site on cells. Many of growth hormone’s effects run through insulin-like growth factor 1 (IGF-1), which the liver makes in response.^1,2,3,4

Sermorelin, tesamorelin and CJC-1295 are lab-made versions of GHRH (GHRH analogs). Ipamorelin and ibutamoren, a small molecule, are ghrelin mimics (ghrelin receptor agonists). All five act through the pituitary, so the FDA notes that people whose pituitary makes no growth hormone will not respond.^1,7,2,3,4

How they work

Sermorelin is the first 29 amino acids of human GHRH. Tesamorelin is a stabilized version of full-length GHRH. CJC-1295 is sermorelin with four amino acids swapped. Its original form adds a chemical link, the drug affinity complex (DAC), that binds it to albumin, a blood protein. Half a dose of this form clears in about a week.^7,2,1,8,9,10

A version without DAC, tetrasubstituted GRF(1-29), is also called CJC-1295. The FDA warns that the inconsistent names could lead a patient to receive a different substance than prescribed.^2,4

Ipamorelin is a chain of five amino acids, some not found in human proteins. In a 1998 study in pigs, it released growth hormone without raising cortisol, a stress hormone, unlike two older peptides, GHRP-2 and GHRP-6.^4,11

AOD-9604, developed as an obesity drug, is the last 15 amino acids of growth hormone with one added. In a 2001 study it reduced body fat in obese mice.^5,12

Why not growth hormone itself?

Growth hormone itself (the ingredient somatropin) is FDA-approved for a short list of conditions, such as growth hormone deficiency in children and adults, but a pharmacy cannot compound it. On March 23, 2020, federal law turned somatropin’s drug approvals into biologics licenses, the approval type for biological products such as proteins. The FDA told compounders that such products no longer qualify for the exemptions for state-licensed pharmacies (section 503A) or FDA-registered outsourcing facilities (section 503B).^{50,51,34,27,36}

Under 21 U.S.C. 333(e), it is a crime to knowingly distribute human growth hormone for use in people, or to possess it with intent to do so. The exception is a physician-ordered treatment of a disease or other recognized medical condition, for a use authorized under the drug-approval law. Prison terms run up to five years, or ten if someone under 18 is involved, and fines can be added.⁵²

How they are taken

Sermorelin went into a vein as a diagnostic test, and under the skin (a subcutaneous injection) as a treatment. Tesamorelin and CJC-1295 are injected under the skin. In trials, ipamorelin went into a vein, ibutamoren by mouth, AOD-9604 by mouth or vein.^{7,13,1,9,14,15,5}

What the research in people shows

Two large (phase 3) trials compared tesamorelin with a placebo for 26 weeks in 412 and 404 adults with HIV and excess abdominal fat. People on it lost more deep belly fat (visceral fat), and the effect faded after switching to placebo. The label says it is not for weight loss, because its effect on weight is neutral.^17,18,37,1

In a 2012 trial, 152 older adults, 66 with mild memory or thinking problems, took tesamorelin or a placebo for 20 weeks. Those on tesamorelin scored better on some thinking tests but had more side effects, all mild: 68 of every 100, against 36 of every 100 on placebo. A six-month 2025 trial in 73 adults with HIV, excess belly fat and impaired thinking found no clear difference from usual care in thinking scores.^8,39

Sermorelin’s evidence comes mostly from children with growth hormone deficiency. In a 1996 study without a comparison group, 110 children took it for up to a year and their growth sped up. In a 1993 randomized trial of 60 children, growth hormone itself worked better over six months.^13,19

In a 1997 study without a comparison group, 11 healthy older men with low IGF-1 took sermorelin for six weeks. Growth hormone rose at night, and two of six strength tests improved, but IGF-1, muscle mass and fat did not change.²⁰

All three published studies of CJC-1295, from 2006 to 2009, gave the DAC version to 63 healthy adults in all. Most got a single injection, and the studies measured hormone levels. The FDA’s 2024 reviews describe no study in people of the version without DAC, or of the CJC-1295 and ipamorelin pairing.^2,9,10,4

A mid-stage (phase 2) trial of CJC-1295 in people with HIV and excess abdominal fat was terminated without published data. Reports the FDA calls anecdotal say a participant died of a heart attack, attributed by the doctor to symptomless coronary artery disease.^21,2

Ipamorelin’s only published trial in patients, from 2014, gave it or a placebo by vein to 114 adults having bowel surgery. How soon they could eat a solid meal was not clearly different. A larger placebo-controlled trial in 320 such patients was completed in 2014, with no results posted.^14,4,48

In a 2008 trial, 65 healthy older adults took ibutamoren or a placebo for a year, some for two. It raised growth hormone, IGF-1 and lean tissue, but not strength or function, which its authors said the trial was too small and short to judge. In a 12-month trial of 563 people with Alzheimer’s disease, it raised IGF-1 but did not slow the disease. Two hip fracture trials, of 161 and 123 older adults, found no consistent improvement.^15,16,22,23

In an 18-month trial published in 2001, 292 women with osteoporosis took ibutamoren, alendronate (an osteoporosis drug), both, or a placebo. Adding ibutamoren raised bone density at one hip site only.⁴⁹

In a late-1990s randomized trial, analyzed in 2021 by the drug’s developer, 68 children with growth hormone deficiency grew faster on ibutamoren than on placebo. The placebo group grew faster still after switching to growth hormone injections. A randomized phase 2 trial of 82 children, reported in 2026, found slower growth on each ibutamoren dose than on growth hormone injections.^40,3,41

AOD-9604 was tested by mouth or vein in six company-funded randomized, placebo-controlled trials in nearly 900 adults. In the largest, 502 adults with obesity took it or a placebo by mouth for 24 weeks, and weight loss was not clearly different. The FDA could not find full results of that trial, or of a 300-person trial.⁵

Side effects and risks

In tesamorelin’s trials, over the first 26 weeks, injection-site reactions affected 25 of every 100 people on it and 14 of every 100 on placebo. Diabetes-range results on the HbA1c blood sugar test appeared in 5 of every 100 on it, against 1 of every 100 on placebo. Allergic reactions affected 4 of every 100 treated. Fluid retention can cause swelling, joint pain and carpal tunnel syndrome, a pinched nerve in the wrist. These pass on their own or after stopping.^1,38

Tesamorelin must not be used during active cancer, because it raises growth hormone, a known growth factor. Any past cancer should be inactive and fully treated first. It is also ruled out in pregnancy, after damage to the hypothalamus or pituitary, and for people allergic to it. Mothers taking it should not breastfeed.^1,38

The label tells prescribers to check blood sugar and IGF-1, and to check people with diabetes for diabetic eye disease (retinopathy). It advises considering stopping tesamorelin in acute critical illness, where growth hormone treatment has increased deaths.^1,38

Ibutamoren’s 2011 hip fracture trial was stopped early when heart failure occurred in 4 of 62 people on it and 1 of 61 on placebo. Blood pressure also rose. In the 2008 healthy-older-adult trial, 19 of 43 on ibutamoren had mild, short-lived leg swelling, against 6 of 22 on placebo. Short-lived muscle pain affected 14 of the 43, against 2 of the 22, and appetite rose in 29, against 8, easing within months.^23,3,15

In the Alzheimer’s trial, blood sugar rose in about 15 of every 100 people on ibutamoren and 5 of every 100 on placebo. The FDA lists high blood sugar, raised liver enzymes, fluid overload and heart failure after hip fracture as serious concerns. Ibutamoren’s trials also reported blood clots, cancer and a heart attack, without showing the drug caused them.^16,3

In the CJC-1295 studies, injection-site reactions were the most common problem, with flushing and a drop in blood pressure, headache, diarrhea and a faster heart rate. The studies called none serious; the FDA’s safety-risk list calls the faster heart rate and the flushing serious.^2,9,25

In the 2014 ipamorelin surgery trial, low potassium and high blood sugar were more common than with placebo. Two people given ipamorelin died after surgical complications; the FDA says it is unclear whether the drug played a part.^14,4

AOD-9604’s safety data come from a developer-written summary of its six trials. Headache was the most common complaint, with diarrhea and gas by mouth. In a 12-week trial of 300 adults, five people on AOD-9604 had serious adverse events: breast cancer, melanoma, basal and squamous cell cancers, and a benign fatty lump. The investigators judged none drug-related; the FDA says the reports lack the detail to tell.^5,25

For CJC-1295, ipamorelin and ibutamoren, the FDA says there are too few data to conclude they avoid the risks on growth hormone labels. Those include tumors, diabetes, fluid retention, raised pressure inside the skull and inflammation of the pancreas. A 2007 systematic review pooled 18 randomized trials in which 220 healthy older adults took growth hormone itself. They had more swelling, joint pain, carpal tunnel syndrome, male breast enlargement and somewhat more diabetes.^2,3,4,24

The FDA is concerned that impurities or clumped peptide in compounded CJC-1295, ipamorelin and AOD-9604 could set off an immune response. In the 1993 trial, 39 of the 40 children given sermorelin made antibodies against it, though antibody levels were not linked to growth. A 1999 review reported brief facial flushing and injection-site pain as its most common side effects.^25,19,7

FDA status

Tesamorelin has been FDA-approved since 2010 to reduce excess abdominal fat in adults with HIV who have lipodystrophy, an abnormal shift of body fat. Neither of its labels, one for a formulation approved in March 2025, carries a boxed warning, the FDA’s most serious kind.^1,26,38

Since 2020 the FDA has regulated tesamorelin as a biological product, which rules out compounding it.^26,51,36

Sermorelin was approved in 1990 as a diagnostic test and in 1997 for children with growth hormone deficiency. Both approvals were withdrawn at the maker’s request in 2009, not for safety or effectiveness reasons, the FDA found in 2013. No sermorelin product is approved today.^6,46,47

No FDA-approved product contains CJC-1295, ipamorelin, ibutamoren or AOD-9604. In a December 2025 warning letter, the FDA determined that ibutamoren does not qualify as a dietary supplement, because it was studied as a drug first.^2,4,3,5,42

Compounded versions

Compounded drugs are not FDA-approved: the FDA does not check their safety, effectiveness or quality before they are sold. CJC-1295, ipamorelin, ibutamoren and AOD-9604 have no US Pharmacopeia quality standard (a USP monograph), and none is in an approved drug. A 503A pharmacy could use them only if they were on the 503A bulks list, the FDA’s list of extra ingredients. None is. In 2024, FDA staff recommended against adding any of the four, and the FDA’s Pharmacy Compounding Advisory Committee voted against each.^{36,31,2,3,4,5,29,30,44}

Ibutamoren is in Category 2 (safety risks) for 503A pharmacies and 503B outsourcing facilities, ipamorelin for outsourcing facilities only. The 503A nominations for ipamorelin, CJC-1295 and AOD-9604 were withdrawn, leaving them outside Category 1, the substances under review whose compounding the FDA does not intend to act against.^{25,32,33,31,2,5}

Sermorelin is in none of the 503A categories, which cover only substances with no USP monograph that are in no FDA-approved drug. The FDA’s outsourcing-facility list places sermorelin acetate in Category 1, marked as a component of FDA-approved drugs: the products withdrawn in 2009.^{31,32,33,6,46,47}

On October 30, 2026, the Department of Health and Human Services (HHS), the FDA’s parent department, published notice of a nonbinding draft policy on six other peptides. They are BPC-157, epitalon, KPV, MOTS-c, semax and TB-500. HHS says it does not intend to take enforcement action against state-licensed pharmacies, federal facilities and licensed physicians compounding them under ten conditions.^53,45

Rules in sport

The World Anti-Doping Agency’s 2026 and 2027 Prohibited Lists ban sermorelin, tesamorelin, CJC-1295, ipamorelin, ibutamoren, AOD-9604 and every compound in the table above, in and out of competition.^35,43

What isn’t known

No published study has tested CJC-1295 for a health outcome in people. For ipamorelin and AOD-9604, the FDA found no study in people giving them by injection under the skin, the route proposed for compounding. The trials here lasted at most two years, and none was designed to detect cancer or heart disease. Tesamorelin’s label says its long-term heart safety has not been established, and the effects of IGF-1 staying high are unknown.^2,4,5,15,1

A placebo-controlled phase 3 trial of ibutamoren began in May 2026 in children with growth hormone deficiency selected as likely to respond.²⁸

Questions to ask a clinician