How long peptides take to work depends on which measurement is meant: a growth hormone pulse follows a GHRH 1-29 dose within 10 minutes and lasts about 2 hours, IGF-1 rose within 2 weeks in the 16-week trial that measured it, and the outcomes the controlled trials were built around were read at 16 to 52 weeks [23, 24]. The pharmacokinetic papers give half-lives from minutes for sermorelin and tesamorelin, through about 2 hours for ipamorelin, to 5.8 to 8.1 days for CJC-1295 [2, 14, 19, 21].
Two clocks answer the question: the molecule’s half-life and the trial’s follow-up schedule. The sections below give both for sermorelin, CJC-1295, ipamorelin, tesamorelin, BPC-157 and GHK-Cu, list the follow-up points the published studies used, and explain why the duration of any program is the prescriber’s decision. It is written for patients who search this question and for the practices that answer it. ExaVeyra Sciences is a supplier, and no sentence here is a schedule.
Regulatory status
As of 5 November 2026, tesamorelin is the only compound in this article marketed as an FDA-approved drug in the United States, and FDA states that compounded drugs are not FDA-approved and that it does not verify their safety, effectiveness or quality before marketing [14, 17]. FDA’s safety-risks page, current as of 22 April 2026, lists BPC-157, CJC-1295, ipamorelin and GHK-Cu for injectable routes among nominations withdrawn from 503A category 2, its nominations list of 14 May 2026 returns GHK-Cu for non-injectable routes to category 1, and the HHS enforcement discretion notice of 30 October 2026 covers BPC-157 and five other peptides but none of the growth hormone secretagogues or GHK-Cu [15, 16, 18]. Sermorelin is compounded by our 503A pharmacy partner against a patient-specific prescription; topical GHK-Cu is available as topical 503A preparations compounded to prescription; BPC-157, CJC-1295, ipamorelin, tesamorelin and other non-catalog peptides are offered for IND-authorized clinical trials through our pharmacy partner, with the sponsor’s IND number, sponsor details and protocol confirmed before any supply. The practitioner decides use and duration.
Understanding the difference between a hormone pulse and a measured outcome
In the trials that sampled it, a secretagogue produced its first measured effect within minutes [24]. Khorram and colleagues sampled blood every 10 minutes overnight in 19 adults aged 55 to 71 and reported in 1997 that a nightly GHRH 1-29 analog induced an acute growth hormone release within 10 minutes that lasted 2 hours [24]. Wilton and colleagues reported in 1993 that GHRH 1-29 was rapidly eliminated after intravenous injection while growth hormone stayed elevated for about 3 hours [22].
The downstream marker moved on a scale of weeks in the same studies [24, 26]. In the same 1997 trial IGF-I and IGFBP-3 rose within 2 weeks, stayed elevated through 12 weeks, and returned toward baseline by week 16 while dosing continued [24]. Corpas and colleagues reported in 1992 that IGF-I rose significantly within 14 days at the higher of two GHRH 1-29 levels in older men [26].
The outcome a trial is built around is read later still, and two short studies recorded a pulse without a downstream change [25, 27]. Vittone and colleagues reported in 1997 that 6 weeks of nightly GHRH 1-29 in 11 older men raised nocturnal growth hormone release without changing IGF-I, IGFBP-3 or GHBP [25], and Nijland and colleagues reported in 1998 that five days of GHRP-2 produced a strong first-day growth hormone peak that attenuated by day 5 with no rise in IGF-I [27].
Published half-lives set the clock for each compound
The 2026 Dominikowski review tabulates sermorelin with a disappearance half-time of about 4.3 minutes, ipamorelin with a half-life of about 2 hours and CJC-1295 with DAC at 5.8 to 8 days, drawing on the primary pharmacokinetic papers [2]. Gobburu and colleagues reported ipamorelin’s 2-hour terminal half-life and a single growth hormone episode peaking at 0.67 hours in healthy volunteers in 1999 [21], and Teichman and colleagues estimated CJC-1295 at 5.8 to 8.1 days in 2006 [19].
The Egrifta label states a mean elimination half-life of 11 minutes for tesamorelin, a median time to peak concentration of 0.15 hours and absolute bioavailability below 4 percent after subcutaneous injection [14]. He and colleagues reported in 2022 that BPC-157 had an elimination half-life under 30 minutes in rats and beagle dogs, with linear kinetics and rapid metabolism, and Mateescu and colleagues reported in 2026 that the only human pharmacokinetic data are a preliminary two-subject pilot [6, 28].
| Compound | Reported half-life | Species | Downstream marker timing | Source |
|---|---|---|---|---|
| Sermorelin (GHRH 1-29) | Minutes (disappearance half-time about 4.3 min) | Human | Growth hormone pulse within 10 min lasting 2 h; IGF-I up within 2 weeks | Dominikowski 2026 [2]; Khorram 1997 [24] |
| Tesamorelin | 11 minutes | Human | IGF-1 above 2 SDS seen as early as 13 weeks; 47% at 26 weeks | Egrifta label 2025 [14] |
| Ipamorelin | About 2 hours | Human | One growth hormone episode peaking at 0.67 h | Gobburu 1999 [21] |
| CJC-1295 (with DAC) | 5.8 to 8.1 days | Human | IGF-I raised 9 to 11 days after one dose; up to 28 days after several | Teichman 2006 [19] |
| BPC-157 | Under 30 minutes | Rat and dog; a two-subject human pilot | No human time course published | He 2022 [6]; Mateescu 2026 [28]; Vasireddi 2025 [5] |
| GHK-Cu (topical) | Not applicable to a topical cream | Human facial studies | Studies read at 12 weeks | Pickart 2015 [11]; Mokhtar 2026 [3] |
IGF-1 responds within days to weeks in the growth hormone trials
Teichman and colleagues reported that a single CJC-1295 injection raised growth hormone 2 to 10 fold for 6 days or more and IGF-I 1.5 to 3 fold for 9 to 11 days, and that after several doses IGF-I stayed above baseline for up to 28 days [19]. Ionescu and Frohman reported in 2006 that the analog raised trough growth hormone 7.5 fold with pulse frequency and amplitude unchanged, and IGF-I by 45 percent [20].
The tesamorelin program measured IGF-1 at fixed visits. The Falutz pooled analysis reported a mean IGF-I rise of 108 nanograms per milliliter at week 26 [23], and the label reports IGF-1 above 2 standard deviation scores in 47 percent of patients at 26 weeks, seen as early as 13 weeks, and in 34 percent of those who continued to 52 weeks [14]. Baker and colleagues reported a 117 percent rise that stayed within the physiological range over 20 weeks in older adults [9].
The question "do peptides raise IGF-1" therefore has a time course: days for the long-acting analog, 2 weeks for GHRH 1-29 in the trial that sampled it, and a plateau or partial return toward baseline by 12 to 16 weeks in that same trial [19, 24]. Stanley and colleagues also showed in 2014 that an early laboratory change can fade: fasting glucose rose on tesamorelin at 2 weeks and the difference was gone at 6 months [8].
Controlled trials measured their outcomes at 6 to 52 weeks
The tesamorelin phase 3 program was built as a 26-week main phase and a 26-week extension, and the pooled analysis reported visceral fat reduction maintained to week 52 in participants who continued [14, 23]. Stanley and colleagues read visceral and liver fat at 6 months in 2014 and hepatic fat at 12 months in 2019, when 35 percent on tesamorelin against 4 percent on placebo reached a hepatic fat fraction under 5 percent [7, 8], and Russo and colleagues read the same outcomes at 12 months in 2024 [13].
The GHRH 1-29 studies in older adults ran 6 weeks, 14 days per dose level, and 16 weeks of active dosing within a 5-month trial, with skin thickness, body composition and insulin sensitivity read at the end [24, 25, 26]. Baker and colleagues read cognitive outcomes at 20 weeks in 2012 and called for longer trials [9]. Badran and colleagues pooled the five tesamorelin trials in 2026 across those 26-week to 12-month endpoints [1].
| Study | Compound | Duration and read point | Outcome measured | Source |
|---|---|---|---|---|
| Corpas 1992 | GHRH 1-29 | 14 days per dose level | Growth hormone and IGF-I | [26] |
| Vittone 1997 | GHRH 1-29 | 6 weeks | Nocturnal growth hormone, IGF-I, muscle strength | [25] |
| Khorram 1997 | GHRH 1-29 analog | 16 weeks of dosing, 5-month trial | IGF-I, skin thickness, body composition, insulin sensitivity | [24] |
| Baker 2012 | Tesamorelin | 20 weeks | Cognition, IGF-1, body fat, fasting insulin | [9] |
| Falutz 2010 (pooled) | Tesamorelin | 26 and 52 weeks | Visceral fat, lipids, IGF-I, glucose | [23] |
| Stanley 2014 and 2019 | Tesamorelin | 6 months; 12 months | Visceral fat, liver fat, glucose, HbA1c | [7, 8] |
| Beck 2014 | Ipamorelin | Up to 7 days | Time to first tolerated meal (hours) | [10] |
| GHK-Cu facial studies | Topical GHK-Cu | 12 weeks | Skin laxity, fine lines, density and thickness | [11] |
The evidence does not yet show several things patients ask about
The published time courses leave specific questions open, and each item below is an absence in the literature as of 5 November 2026 that carries no finding either way. The 2026 orthopedic primer states the gap directly: indications, frequency and duration for these peptides remain unknown [12].
- No controlled trial defines how long a sermorelin, CJC-1295 or ipamorelin program should run, so "how long is a peptide cycle" has no published answer [12].
- No trial of any secretagogue reports what happens to IGF-1 or body composition after the compound is stopped; the closest data are the 52-week tesamorelin extension and the 28-day IGF-I tail after CJC-1295 [19, 23].
- No human pharmacokinetic study of BPC-157 beyond a two-subject pilot has been reported, and the one clinical report is an uncontrolled series of 12 patients [5, 6, 28].
- No indexed randomized trial of topical GHK-Cu reports a time course beyond 12 weeks, and the 2025 review describes a surprising absence of clinical studies [3, 4].
- No study shows that an early IGF-1 rise predicts a later clinical outcome for a compounded secretagogue; the 1997 trial saw IGF-I return toward baseline by week 16 while dosing continued [24].
BPC-157 and GHK-Cu timelines come from animal and topical studies
Vasireddi and colleagues reviewed 36 BPC-157 studies in 2025 and found 35 preclinical and one clinical, an uncontrolled series in which 7 of 12 patients with chronic knee pain reported relief for more than six months after one injection, with no clinical safety data [5]. He and colleagues measured a half-life under 30 minutes in rats and dogs in 2022 [6], so the question "how long does BPC-157 take to work" has animal pharmacokinetics, a two-subject human pilot and one uncontrolled clinical report behind it [5, 28].
GHK-Cu is a topical question. Pickart and colleagues summarized facial studies of 12 weeks in 71 women and 67 women and a 12-week eye cream study in 41 women in their 2015 review, studies reported at conferences rather than in indexed trials [11]. Mokhtar and colleagues found 20 studies in their 2026 systematic review, 18 preclinical and two randomized trials, and called for larger controlled trials with standardized formulations [3], while Mortazavi and colleagues described a surprising absence of clinical studies of GHK-Cu in 2025 [4].
The regulatory positions differ as well. FDA’s safety-risks page lists BPC-157 and GHK-Cu for injectable routes among withdrawn 503A nominations, its nominations list of 14 May 2026 returned GHK-Cu for non-injectable routes to category 1 with an advisory committee consult planned before the end of February 2027, and the HHS notice of 30 October 2026 names BPC-157 among six peptides covered by an interim enforcement discretion policy described as a draft that is not binding [15, 16, 18]. Topical GHK-Cu is available as topical 503A preparations compounded to prescription, and BPC-157 is offered for IND-authorized clinical trials through our pharmacy partner.
Clearance times answer how long a peptide stays in the system
A compound is conventionally considered cleared after about five half-lives, so the pharmacokinetic papers give the ranges: under an hour for sermorelin and tesamorelin, under a day for ipamorelin, and several weeks for CJC-1295 with DAC [2, 14, 21]. Teichman and colleagues measured the tail directly, with IGF-I above baseline for up to 28 days after repeated CJC-1295 doses [19].
Whether results last is a separate question from whether the molecule remains. The pooled tesamorelin analysis reported visceral fat reduction maintained to week 52 in participants who continued [23], and no trial of a compounded secretagogue reports outcomes after stopping, which is the gap listed above [12]. The 1997 GHRH 1-29 trial is the caution in the other direction: IGF-I drifted back toward baseline by week 16 while dosing continued [24].
The molecule’s clock runs in minutes to days; the trial’s clock runs in weeks to a year; neither sets the length of a program, which is the prescriber’s decision.
Program duration is the prescriber’s decision and the supply route is documented
FDA states that compounded drugs should only be used in patients whose medical needs cannot be met by an FDA-approved drug [17], and the trials above are the only published guide to how long a measurement takes. The length of any program, the intervals at which IGF-1 or glucose are checked, and the point at which a program ends are decisions for the prescriber, who holds the patient’s record and the trial literature together.
Sermorelin is compounded by our 503A pharmacy partner against a patient-specific prescription, with the partner holding nonresident licenses in 33 jurisdictions including Puerto Rico; topical GHK-Cu is available as topical 503A preparations compounded to prescription; and BPC-157, CJC-1295, ipamorelin, tesamorelin and other non-catalog peptides are offered for IND-authorized clinical trials through our pharmacy partner, with the sponsor’s IND number, sponsor details and protocol confirmed before any supply.
A verified account keeps the timeline and the documentation together
A practice that can show a patient the half-life of the molecule, the week at which the trials read IGF-1, and the month at which they read an outcome is answering "how long do peptides take to work" with sources. ExaVeyra supports that work as a supplier: it connects NPI-verified practices with its 503A pharmacy partner for sermorelin, topical GHK-Cu and the hormone optimization line, and routes IND-authorized trial requests for non-catalog peptides through the same partner once the sponsor’s IND number, sponsor details and protocol are confirmed.
Anyone may ask the scientific team a question or apply without an NPI, review takes 1 to 3 business days, and NPI verification gives access to the practitioner portal, product documentation and pricing. Product names mentioned in this article are trademarks of their owners and are used only to identify the products discussed. The trials that exist already show how a time course is measured well, and practices that keep their own records to that standard are ready for the longer studies the field is moving toward.
Educational Disclaimer: This article is for educational purposes only and does not constitute medical or legal advice. It does not identify any material, compound, device setting or protocol as safe, effective or appropriate for any patient, and it is not intended to diagnose, treat, cure, or prevent any disease. Questions about a treatment belong with the reader’s own licensed provider. Exosome material is supplied for topical aesthetic use by licensed practitioners. No exosome product is FDA-approved for any use, and ExaVeyra Sciences makes no statement about administration, route, or outcome. Compounded medications are not FDA-approved. They are prepared by a 503A compounding pharmacy licensed by the Texas State Board of Pharmacy for an individual patient against that patient’s prescription, and are available to NPI-verified licensed practitioners only, in the states where the pharmacy is licensed. Product, device and brand names mentioned are trademarks of their respective owners and are used only to identify the products discussed. Their mention is not an endorsement, and those owners have not reviewed or endorsed this article. ExaVeyra Sciences is a supplier and takes no part in any diagnosis, treatment decision, or plan of care. Findings described are attributed to the peer-reviewed literature, trial registries and agencies cited. The content of these guides is provided for general informational purposes only. It does not constitute legal, medical, or regulatory advice, and does not establish that any particular product or practice is compliant. Regulatory requirements vary by state and depend on the circumstances of each practice. Each practitioner should consult their own legal counsel and the applicable state licensing boards before acting on anything stated here.
References
- 1.Badran AS, Helal A, Shata KS, Ayesh H. Body composition, hepatic fat, metabolic, and safety outcomes of Tesamorelin, a GHRH analogue, in HIV-associated lipodystrophy: A meta-analysis of randomized controlled trials. Obes Res Clin Pract. 2026;20(1):2-12. PMID 41545261. doi:10.1016/j.orcp.2026.01.002Meta-analysis of five randomized controlled trials of tesamorelin. Carries in this article: the pooled visceral fat, lean mass and hepatic fat changes measured at the trials’ 26-week to 12-month endpoints, the benchmark for how long a growth hormone axis outcome took to measure in controlled conditions. Disclosure: none stated in the PubMed record.
- 2.Dominikowski A, Rękoś Z, Olejarz M, Szczepanek-Parulska E, Domin R, Ruchała M. The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration. Front Endocrinol (Lausanne). 2026;17:1822475. PMID 42395176. doi:10.3389/fendo.2026.1822475Narrative review from an academic endocrinology department, searches to January 2026, read in full text through PubMed Central. Carries in this article: the half-life table (sermorelin disappearance half-time about 4.3 minutes, ipamorelin about 2 hours, CJC-1295 with DAC 5.8 to 8 days) and the finding of no long-term data for any of the unapproved compounds. Disclosure: academic authors; no funding statement in the PubMed record.
- 3.Mokhtar J, Mohamad B, Haddad J, Said A, Menon A, Kreutz-Rodrigues L, et al. The Regenerative Potential of GHK-Cu in Aesthetic Medicine. Aesthet Surg J. 2026. Published online ahead of print. PMID 42619529. doi:10.1093/asj/sjag169PRISMA systematic review, searches to March 2026; 20 studies, 18 preclinical and 2 randomized trials. Carries in this article: the clinical findings were limited to two randomized trials, and the authors call for larger controlled trials with standardized formulations. Disclosure: academic plastic surgery authors; no COI statement in the PubMed record.
- 4.Mortazavi SM, Mohammadi Vadoud SA, Moghimi HR. Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. Bioimpacts. 2025;15:30071. PMID 39963574. doi:10.34172/bi.30071Narrative review of topical GHK and GHK-Cu formulation science. Carries in this article: the authors report a surprising absence of clinical studies of GHK-Cu and palmitoyl-GHK despite their use in anti-wrinkle products, and describe the permeation challenges of a hydrophilic peptide. Disclosure: academic pharmaceutics authors; none stated in the PubMed record.
- 5.Vasireddi N, Hahamyan H, Salata MJ, Karns M, Calcei JG, Voos JE, et al. Emerging Use of BPC-157 in Orthopaedic Sports Medicine: A Systematic Review. HSS J. 2025;21(4):485-495. PMID 40756949. doi:10.1177/15563316251355551Systematic review, searches to June 2024; 36 studies, 35 preclinical and 1 clinical. Carries in this article: the one human report was an uncontrolled series of 12 patients, the authors note a half-life under 30 minutes, and they found no clinical safety data, so no human time course for BPC-157 exists. Disclosure: authors declare no conflicts, as the record states.
- 6.He L, Feng D, Guo H, Zhou Y, Li Z, Zhang K, et al. Pharmacokinetics, distribution, metabolism, and excretion of body-protective compound 157, a potential drug for treating various wounds, in rats and dogs. Front Pharmacol. 2022;13:1026182. PMID 36588717. doi:10.3389/fphar.2022.1026182Preclinical pharmacokinetic study in rats and beagle dogs. Carries in this article: an elimination half-life under 30 minutes, linear kinetics, intramuscular bioavailability of 14 to 19 percent in rats and 45 to 51 percent in dogs, and rapid metabolism, all animal data. Disclosure: academic pharmacy authors (China); none stated in the PubMed record.
- 7.Stanley TL, Fourman LT, Feldpausch MN, Purdy J, Zheng I, Pan CS, et al. Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial. Lancet HIV. 2019;6(12):e821-e830. PMID 31611038. doi:10.1016/S2352-3018(19)30338-8Randomized, double-blind trial of 61 patients with a 12-month endpoint. Carries in this article: hepatic fat fell by an absolute 4.1 percentage points at 12 months, with 35 percent against 4 percent reaching a hepatic fat fraction under 5 percent, the longest single endpoint in the tesamorelin trials cited. Disclosure: NIH funded, as the record states.
- 8.Stanley TL, Feldpausch MN, Oh J, Branch KL, Lee H, Torriani M, et al. Effect of tesamorelin on visceral fat and liver fat in HIV-infected patients with abdominal fat accumulation: a randomized clinical trial. JAMA. 2014;312(4):380-9. PMID 25038357. doi:10.1001/jama.2014.8334Randomized clinical trial of 48 patients over 6 months. Carries in this article: fasting glucose rose at 2 weeks and the difference was gone at 6 months, while visceral fat and liver fat changes were measured at the 6-month endpoint, an example of an early laboratory change and a later outcome in the same trial. Disclosure: NIH funded with drug supplied by the manufacturer, as the record states.
- 9.Baker LD, Barsness SM, Borson S, Merriam GR, Friedman SD, Craft S, et al. Effects of growth hormone-releasing hormone on cognitive function in adults with mild cognitive impairment and healthy older adults: results of a controlled trial. Arch Neurol. 2012;69(11):1420-9. PMID 22869065. doi:10.1001/archneurol.2012.1970Randomized, double-blind, placebo-controlled 20-week trial of tesamorelin in older adults (NCT00257712). Carries in this article: the 20-week endpoint, IGF-1 up 117 percent within the physiological range, and the authors’ call for longer trials. Disclosure: NIH funded, as the record states.
- 10.Beck DE, Sweeney WB, McCarter MD, Ipamorelin 201 Study Group. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis. 2014;29(12):1527-34. PMID 25331030. doi:10.1007/s00384-014-2030-8Randomized, placebo-controlled phase 2 trial; 117 enrolled, 114 analyzed, up to 7 days of dosing. Carries in this article: the only randomized efficacy trial of ipamorelin located measured its endpoint in hours and found no significant difference from placebo. Disclosure: industry-sponsored study group, as the author list states.
- 11.Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int. 2015;2015:648108. PMID 26236730. doi:10.1155/2015/648108Narrative review by the peptide’s discoverer, read in full text through PubMed Central. Carries in this article: the facial studies it summarizes ran 12 weeks (71 women, 67 women and a 41-woman eye cream study), the durations most GHK-Cu timelines trace back to; the underlying studies are conference and industry reports rather than indexed trials. Disclosure: first author holds patents on the peptide, as the full text states.
- 12.Mayfield CK, Bolia IK, Feingold CL, Lin EH, Liu JN, Rick Hatch GF, et al. Injectable Peptide Therapy: A Primer for Orthopaedic and Sports Medicine Physicians. Am J Sports Med. 2026;54(1):223-229. PMID 41476424. doi:10.1177/03635465251357593Narrative primer from an academic orthopedic department. Carries in this article: the authors state that indications, frequency and duration for BPC-157, TB-500, CJC-1295, ipamorelin and GHK-Cu remain unknown, the direct answer to any "how long is a cycle" question. Disclosure: none stated in the PubMed record.
- 13.Russo SC, Ockene MW, Arpante AK, Johnson JE, Lee H, Toribio M, et al. Efficacy and safety of tesamorelin in people with HIV on integrase inhibitors. AIDS. 2024;38(12):1758-1764. PMID 38905488. doi:10.1097/QAD.0000000000003965Secondary analysis of a randomized, placebo-controlled 12-month trial; 38 participants. Carries in this article: the 12-month endpoint for visceral and hepatic fat, with adverse event frequency similar between groups. Disclosure: two authors report consulting for the manufacturer and others; stated in the PubMed record.
- 14.U.S. Food and Drug Administration. EGRIFTA WR (tesamorelin for injection) prescribing information, BLA 022505, revised March 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/022505s020lbl.pdf (verified 4 November 2026)Approved product label, downloaded and read 4 November 2026. Carries in this article: mean elimination half-life of 11 minutes, median time to peak concentration of 0.15 hours, absolute bioavailability below 4 percent, IGF-1 above 2 standard deviation scores in 47 percent at 26 weeks and seen as early as 13 weeks, and the two phase 3 studies built as a 26-week main phase and a 26-week extension.
- 15.U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Content current as of 22 April 2026. https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks (verified 5 November 2026)Agency web page with the category 2 table and the nominated but withdrawn table, read 4 and 5 November 2026. Carries in this article: BPC-157, CJC-1295 and GHK-Cu for injectable routes sit in the withdrawn table with FDA’s rationale, ipamorelin acetate sits in both tables (withdrawn under 503A, category 2 under 503B), and sermorelin and tesamorelin have no entry.
- 16.U.S. Food and Drug Administration. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act (categories 1, 2 and 3). Updated 14 May 2026. https://www.fda.gov/media/94155/download (verified 5 November 2026)Agency list of nominated substances by interim category, a seven-page PDF read 4 and 5 November 2026 (unchanged between reads). Carries in this article: GHK-Cu except for injectable routes of administration was returned to category 1 after a nominator clarified on 5 May 2026 that it withdrew only the injectable route, and FDA states it intends to consult the advisory committee on GHK-Cu before the end of February 2027; sermorelin appears in none of the three categories.
- 17.U.S. Food and Drug Administration. Compounding and the FDA: Questions and Answers. Content current as of 16 September 2025. https://www.fda.gov/drugs/human-drug-compounding/compounding-and-fda-questions-and-answers (verified 4 November 2026)Agency questions and answers page, read 4 November 2026. Carries in this article: compounded drugs are not FDA-approved, FDA does not verify their safety, effectiveness or quality before marketing, and they should only be used in patients whose medical needs cannot be met by an FDA-approved drug.
- 18.U.S. Department of Health and Human Services, Office of the Secretary. Enforcement Discretion Policy Regarding 503A Compounding Using Certain Peptide Bulk Drug Substances; notice of availability. Federal Register. 2026;91(209):68526-68527. FR Doc 2026-22192. Docket HHS-OASH-2026-0496. https://www.federalregister.gov/documents/2026/10/30/2026-22192/enforcement-discretion-policy-regarding-503a-compounding-using-certain-peptide-bulk-drug-substances (verified 5 November 2026)Agency notice of 30 October 2026, read in full text through the Federal Register API on 5 November 2026. Carries in this article: HHS does not intend to take enforcement action against a state-licensed pharmacy, Federal facility or licensed physician compounding with a peptide in the policy’s Appendix A while the 503A bulks list is developed through rulemaking; the policy is described as a draft that is not binding and takes comments to 13 November 2026. The policy covers BPC-157, epitalon, KPV, MOTS-c, semax and TB-500; GHK-Cu, CJC-1295, ipamorelin, sermorelin and tesamorelin are outside it. The policy PDF on hhs.gov returned an access-denied page to an automated request on 5 November 2026, so the six-peptide scope is taken from the site’s regulatory update article, which read it on publication.
- 19.Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805. PMID 16352683. doi:10.1210/jc.2005-1536Two randomized, placebo-controlled ascending-dose trials of 28 and 49 days in healthy adults. Carries in this article: half-life 5.8 to 8.1 days, growth hormone raised for 6 days or more and IGF-I for 9 to 11 days after one injection, and IGF-I above baseline for up to 28 days after several. Disclosure: first author at a contract pharmacology consultancy and the sponsor among the authors, as the record states.
- 20.Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. J Clin Endocrinol Metab. 2006;91(12):4792-7. PMID 17018654. doi:10.1210/jc.2006-1702Frequent-sampling pharmacodynamic study in healthy adults. Carries in this article: trough growth hormone raised 7.5 fold with pulse frequency and amplitude unchanged, mean growth hormone up 46 percent and IGF-I up 45 percent, the pattern behind a days-long analog. Disclosure: none stated in the PubMed record.
- 21.Gobburu JV, Agersø H, Jusko WJ, Ynddal L. Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. 1999;16(9):1412-6. PMID 10496658. doi:10.1023/a:1018955126402Dose-escalation pharmacokinetic study in healthy volunteers. Carries in this article: terminal half-life of 2 hours and a single growth hormone episode peaking at 0.67 hours and declining to negligible levels, so each ipamorelin dose is one pulse. Disclosure: two authors at the developer, as the affiliations state.
- 22.Wilton P, Chardet Y, Danielson K, Widlund L, Gunnarsson R. Pharmacokinetics of growth hormone-releasing hormone(1-29)-NH2 and stimulation of growth hormone secretion in healthy subjects after intravenous or intranasal administration. Acta Paediatr Suppl. 1993;388:10-5. PMID 8329825. doi:10.1111/j.1651-2227.1993.tb12827.xPharmacokinetic study of GHRH 1-29, the sermorelin sequence, in 30 healthy men. Carries in this article: rapid elimination after intravenous injection with growth hormone elevated for about 3 hours, the minutes-to-hours window of a sermorelin pulse. Disclosure: authors at the manufacturer of the time, as the affiliation states.
- 23.Falutz J, Mamputu JC, Potvin D, Moyle G, Soulban G, Loughrey H, et al. Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in human immunodeficiency virus-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data. J Clin Endocrinol Metab. 2010;95(9):4291-304. PMID 20554713. doi:10.1210/jc.2010-0490Pooled analysis of the two phase 3 trials with 26-week extension. Carries in this article: the 26-week and 52-week measurement points, mean IGF-I up 108 nanograms per milliliter at week 26, and visceral fat reduction maintained to week 52 in participants who continued. Disclosure: manufacturer-sponsored, as the record states.
- 24.Khorram O, Laughlin GA, Yen SS. Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and women. J Clin Endocrinol Metab. 1997;82(5):1472-9. PMID 9141536. doi:10.1210/jcem.82.5.3943Single-blind, randomized, placebo-controlled 5-month trial of a GHRH 1-29 analog in 19 adults aged 55 to 71, with 16 weeks of active dosing. Carries in this article: an acute growth hormone pulse within 10 minutes lasting 2 hours, IGF-I and IGFBP-3 up within 2 weeks and elevated through 12 weeks before returning toward baseline by week 16 while dosing continued, and skin thickness measured at 16 weeks. Disclosure: none stated in the PubMed record.
- 25.Vittone J, Blackman MR, Busby-Whitehead J, Tsiao C, Stewart KJ, Tobin J, et al. Effects of single nightly injections of growth hormone-releasing hormone (GHRH 1-29) in healthy elderly men. Metabolism. 1997;46(1):89-96. PMID 9005976. doi:10.1016/s0026-0495(97)90174-8Six-week study of nightly GHRH 1-29 in 11 healthy men aged 64 to 76 with low baseline IGF-I. Carries in this article: nocturnal growth hormone release rose while IGF-I, IGFBP-3 and GHBP did not change at 6 weeks, an example of a hormone pulse without a measured downstream change inside a short window. Disclosure: none stated in the PubMed record.
- 26.Corpas E, Harman SM, Piñeyro MA, Roberson R, Blackman MR. Growth hormone (GH)-releasing hormone-(1-29) twice daily reverses the decreased GH and insulin-like growth factor-I levels in old men. J Clin Endocrinol Metab. 1992;75(2):530-5. PMID 1379256. doi:10.1210/jcem.75.2.1379256Crossover study of GHRH 1-29 in 10 healthy older men against 9 young men, 14 days per dose level. Carries in this article: IGF-I rose significantly within 14 days at the higher dose level, with fasting glucose unaffected, the earliest IGF-I time point among the GHRH 1-29 studies cited. Disclosure: National Institute on Aging authors, as the affiliation states.
- 27.Nijland EA, Strasburger CJ, Popp-Snijders C, van der Wal PS, van der Veen EA. A five day treatment with daily subcutaneous injections of growth hormone-releasing peptide-2 causes response attenuation and does not stimulate insulin-like growth factor-I secretion in healthy young men. Eur J Endocrinol. 1998;139(4):395-401. PMID 9820615. doi:10.1530/eje.0.1390395Five-day study in 9 healthy young men. Carries in this article: the growth hormone peak fell from 83 to 51 micrograms per liter across five days and IGF-I did not rise, so a strong first pulse did not translate into a downstream marker within that window. Disclosure: none stated in the PubMed record.
- 28.Mateescu DM, Gavrilescu DM, Constantinescu FE, Oancea C, Ilie AC, Folescu R, et al. BPC-157 as an Investigational Peptide Therapeutic: Biopharmaceutical Challenges, Formulation Strategies, and Translational Development Barriers. Pharmaceutics. 2026;18(5):625. PMID 42198317. doi:10.3390/pharmaceutics18050625Narrative review of PubMed, Embase and Cochrane to April 2026 with patent and regulatory agency searches. Carries in this article: a plasma half-life under 30 minutes confirmed preclinically and in a preliminary two-subject human pilot, the only human pharmacokinetic data the review reports for BPC-157. Funding: a university in Romania; the authors declare no conflicts.