Capromorelin

updated

Capromorelin is an oral ghrelin receptor agonist that FDA has approved only for animals: appetite stimulation in dogs and weight loss in cats with chronic kidney disease. Its human record is one 395-person trial in adults aged 65 to 84, stopped early, which found lean body mass up 1.4 kg versus 0.3 kg on placebo at 6 months, and one single-dose phase 1 study. No study compares it with injectable growth hormone releasing peptides.

Ghrelin receptor agonist (growth hormone secretagogue)

  • FDA approved ENTYCE for appetite stimulation in dogs on 16 May 2016 and ELURA for management of weight loss in cats with chronic kidney disease on 16 October 2020. A search on 9 October 2026 found no human drug application.
  • In 177 dogs with reduced appetite, owner-scored success was 68.6% with ENTYCE versus 44.6% with vehicle control (p=0.0078). In 112 cats with chronic kidney disease, body weight changed by +5.2% versus -1.6% (p<0.0001).
  • In 395 adults aged 65 to 84, lean body mass rose 1.4 kg versus 0.3 kg on placebo at 6 months (P=0.001) in a trial that was terminated early.
  • In 6 beagles dosed for 7 days, the GH rise was smaller on days 4 and 7 than on day 1, while the IGF-1 rise was sustained through day 7.
  • A PubMed search on 9 October 2026 for capromorelin with injectable growth hormone releasing peptides returned 3 records; none compared them in people.
  • The dog label states that ENTYCE is not for use in humans.

What is capromorelin, and who has approved it?

Capromorelin is an oral ghrelin receptor agonist. FDA has approved it only for animals: ENTYCE for appetite stimulation in dogs (2016) and ELURA for weight loss in cats with chronic kidney disease (2020). A search on 9 October 2026 found no human drug application and no ClinicalTrials.gov record.

Capromorelin (code name CP-424391) is a small-molecule ghrelin receptor agonist. The free base is PubChem CID 216208 (C28H35N5O4, molecular weight 505.6, CAS 193273-66-4). The salt in both approved products is capromorelin tartrate (CID 9852610, C32H41N5O10, molecular weight 655.7, CAS 193273-69-7). Listed synonyms include CP-424391, Entyce and Elura. Both FDA labels give the empirical formula C28H35N5O4 and C4H6O6 with molecular weight 655.70, which is the tartrate. Product strengths are expressed as capromorelin, so a vendor powder sold as capromorelin may be either the base or the tartrate, and the two differ by about 23% in mass.

FDA has approved capromorelin only as animal drugs. ENTYCE oral solution (NADA 141-457) is approved for appetite stimulation in dogs. FDA approved it on 16 May 2016, per a Federal Register rule of 29 August 2016 (81 FR 59131) that also added 21 CFR 520.292. ELURA oral solution (NADA 141-536) is approved for management of weight loss in cats with chronic kidney disease. FDA approved it on 16 October 2020, per a Federal Register rule of 1 April 2021 (86 FR 17061). A Federal Register notice of 11 January 2018 (83 FR 1365) records that NADA 141-457 was submitted on 22 March 2016 and approved on 16 May 2016, and that approval of ENTYCE was the first permitted commercial marketing of the product.

The dog label states that ENTYCE is not for use in humans and that its effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study. The label versions used here took effect on 19 November 2025 (ENTYCE) and 11 November 2025 (ELURA). An openFDA Drugs@FDA substance-name query for capromorelin on 9 October 2026 returned no matching human drug application, and a ClinicalTrials.gov term search returned 0 records. Approvals outside the United States are not covered here.

PubChem: capromorelin base and tartrate identity

Chemical identity record

National Library of Medicine. PubChem compound record CID 216208 (capromorelin), with the tartrate salt at CID 9852610.

Capromorelin free base is PubChem CID 216208: C28H35N5O4, molecular weight 505.6, CAS 193273-66-4. The salt in both approved products is capromorelin tartrate: CID 9852610, C32H41N5O10, molecular weight 655.7, CAS 193273-69-7. Listed synonyms include CP-424391, Entyce and Elura. Both FDA labels give the empirical formula C28H35N5O4 and C4H6O6 with molecular weight 655.70, which is the tartrate.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule and tartrate salt
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Product strengths are expressed as capromorelin, so a vendor powder sold as capromorelin may be either the base or the tartrate, and the two differ by about 23% in mass.

Read the original source
ENTYCE dog label, version effective 19 November 2025: approval, field studies, PK, safety

Official label

DailyMed, U.S. National Library of Medicine. ENTYCE (capromorelin oral solution) for dogs, FDA-approved animal drug label under NADA 141-457, label version effective 19 November 2025. Set ID 0a403b74-72be-4f90-a069-d747caea1247.

ENTYCE is FDA-approved under NADA 141-457 for appetite stimulation in dogs. The label describes a selective ghrelin receptor agonist that binds receptors in the hypothalamus to stimulate appetite and the growth hormone secretagogue receptor in the pituitary to increase growth hormone secretion. It states that effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study, that the product is not for use in humans, and that it may be dermally absorbed. In 24 healthy Beagles, food consumption rose significantly over 4 days (p<0.001). In a clinical field study of 177 dogs (121 ENTYCE, 56 vehicle control) with reduced or absent appetite for at least 2 days, owner-scored treatment success was 68.6% (n=83) versus 44.6% (n=25), p=0.0078. In 12 Beagles after an oral dose, mean Tmax was 0.83 hours, mean Cmax 330 ng/mL, mean AUCt 655 ng.hr/mL, mean AUCinf 695 ng.hr/mL and mean terminal half-life 1.19 hours, with mean absolute oral bioavailability of 44%, mean total plasma clearance of 18.9 mL/min/kg, volume of distribution of 2.0 L/kg and unbound plasma fraction of 51%. Metabolism is mainly CYP3A4 and CYP3A5; excretion within 72 hours was 37% urine and 62% feces. In a controlled field study of 244 dogs (171 ENTYCE, 73 vehicle control), diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in all groups given capromorelin, with increased liver weights and hepatocellular cytoplasmic vacuolation, and decreased red blood cell count, hemoglobin and hematocrit at 40 mg/kg.

Participants / model
Dogs: 24 healthy Beagles, 177 dogs in the effectiveness field study, 244 dogs in the controlled field study, 12 Beagles for pharmacokinetics, 32 healthy Beagles in the 12-month study
Treatment
ENTYCE capromorelin oral solution, by mouth
Follow-up
Label version effective 19 November 2025; field studies of 4 days; laboratory study of 12 months
Study design
Official FDA animal drug label
Funding
not stated in the source

These are dog numbers and do not transfer to people. The label states the product is not for use in humans.

Read the original source
ELURA cat label, version effective 11 November 2025: approval, field study, safety

Official label

DailyMed, U.S. National Library of Medicine. ELURA (capromorelin oral solution) for cats, FDA-approved animal drug label under NADA 141-536, label version effective 11 November 2025. Set ID be4beb9c-f39b-4b23-9c35-f72a049a3250.

ELURA is FDA-approved under NADA 141-536 for management of weight loss in cats with chronic kidney disease. The label says it binds receptors in the hypothalamus to stimulate appetite and in the pituitary to stimulate GH secretion, that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH but that this is unknown in cats. It is not for use in cats with hypersomatotropism (acromegaly), may increase serum glucose for several hours after dosing, and causes transient decreases in heart rate and blood pressure up to 4 hours after dosing. In a multicenter masked randomized vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg) treated for 56 days, percent change in body weight from day 0 to day 55 in the 112 cats in the effectiveness analysis was +5.2% with ELURA versus -1.6% with vehicle control, p<0.0001, with least squares mean differences of +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. In the field study (118 ELURA, 58 vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation 21.2% versus 0.0%, inappetence 18.6% versus 12.0%, behavior change 14.4% versus 5.2%, anemia 9.3% versus 1.7%, CKD stage increased 8.5% versus 5.2% and hyperglycemia 6.8% versus 3.4%, with diabetes mellitus in 1 cat and congestive heart failure in 1 cat. Nine cats (8 ELURA, 1 vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. In a 32-day telemetry study in 8 healthy juvenile male cats, heart rate and blood pressure fell transiently with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic), returning to baseline within 4 hours; blood glucose rose in 4 cats, with one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 10.5 mg/kg was euthanized for diabetic ketoacidosis.

Participants / model
Cats: 176 client-owned cats with chronic kidney disease in the field study; 8 healthy juvenile male cats in the telemetry study; 32 healthy cats in the 6-month study
Treatment
ELURA capromorelin oral solution, by mouth
Follow-up
Label version effective 11 November 2025; field study of 56 days; telemetry study of 32 days; margin-of-safety study of 6 months
Study design
Official FDA animal drug label
Funding
not stated in the source

The endpoint is body weight, not lean mass. These are cat numbers and do not transfer to people.

Read the original source
Federal Register: ENTYCE 2016 and ELURA 2020 veterinary approvals

Regulatory record

U.S. Food and Drug Administration. New Animal Drugs; Approval of New Animal Drug Applications. Federal Register, 29 August 2016, 81 FR 59131 (NADA 141-457, ENTYCE; adds 21 CFR 520.292). Also 1 April 2021, 86 FR 17061 (NADA 141-536, ELURA), and 11 January 2018, 83 FR 1365.

FDA approved NADA 141-457 (ENTYCE, capromorelin oral solution, dogs, appetite stimulation) on 16 May 2016, per the Federal Register rule of 29 August 2016 (81 FR 59131), which also added 21 CFR 520.292. FDA approved NADA 141-536 (ELURA, capromorelin oral solution, management of weight loss in cats with chronic kidney disease) on 16 October 2020, per the Federal Register rule of 1 April 2021 (86 FR 17061). A Federal Register notice of 11 January 2018 (83 FR 1365) records that NADA 141-457 was submitted on 22 March 2016 and approved on 16 May 2016, and that approval of ENTYCE was the first permitted commercial marketing of the product. Both approvals are animal drug approvals.

Participants / model
Not a clinical population
Treatment
Animal drug applications
Follow-up
Approvals in 2016 and 2020
Study design
Official US government record
Funding
not stated in the source

Both approvals are for animals. No approval for use in people is recorded.

Read the original source
Searches, 9 October 2026: no human comparison with injectable peptides, no human application

PubMed search record

PubMed search run on 9 October 2026: capromorelin AND (GHRP-2 OR GHRP-6 OR ipamorelin OR hexarelin OR pralmorelin OR growth hormone releasing peptide), 3 records. ClinicalTrials.gov term search for capromorelin and openFDA Drugs@FDA substance-name query for capromorelin, same day.

The PubMed search returned 3 records: a mouse gastric-emptying comparison of ghrelin, GHRP-6 and capromorelin, the Pfizer preclinical pharmacology report, and a rabbit cardiac ischemia study. None compared capromorelin with an injectable GHRP in people, and none measured muscle mass in people. A ClinicalTrials.gov term search for capromorelin returned 0 records, and an openFDA Drugs@FDA substance-name query for capromorelin returned no matching human drug application. The compound's only approvals are the two veterinary NADAs.

Participants / model
Records returned, not a population
Treatment
Not applicable
Follow-up
Searches run on 9 October 2026
Study design
Literature, registry and regulator searches
Funding
not stated in the source

A search result shows what the databases returned on that date. It is not proof that no unindexed study exists.

Read the original source

What have studies in people found?

One randomized trial in 395 adults aged 65 to 84 found a sustained rise in IGF-1 and, at 6 months, body weight up 1.4 kg versus down 0.2 kg on placebo and lean body mass up 1.4 versus 0.3 kg. A single-dose phase 1 study reported no serious adverse events.

The largest human study was a randomized, double-masked, placebo-controlled multicenter trial in 395 men and women aged 65 to 84 with mild functional limitation. Participants received oral capromorelin in one of four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night or 10 mg twice a day) or placebo, for an intended 2 years. The study was terminated early according to predetermined treatment effect criteria; 315 participants completed 6 months and 284 completed 12 months.

IGF-1 rose in a sustained, dose-related way in every active group, and each regimen raised peak nocturnal GH, most with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment groups versus placebo. By 12 months stair climb also improved (P=0.04).

A single-center, single ascending dose phase 1 trial gave oral capromorelin at 20, 50 and then 100 mg, at least 1 week apart, to spinal cord injured and able-bodied adult volunteers, with 12 hours of pharmacokinetic sampling and 1-week and 4-week safety follow-up. No serious adverse events were recorded in either group, blood pressure and heart rate showed no abnormal changes, and minor adverse events resolved quickly. Cmax and AUC rose with dose in both groups. Spinal cord injured participants showed greater variance in pharmacokinetic parameters and a slightly delayed Tmax and half-life. The published abstract gives no numeric pharmacokinetic values, so none are given here.

These two studies are the whole human file in the records reviewed. The muscle result is limited to adults aged 65 to 84 with mild functional limitation, and nothing on muscle in healthy or trained people was found.

Older adults: 395 randomized, stopped early, lean body mass +1.4 versus +0.3 kg at 6 months

Randomized controlled trial

White HK et al. J Clin Endocrinol Metab. 2009;94(4):1198-206. PMID 19174493.

A sustained dose-related rise in IGF-1 occurred in all active groups, and each dose produced a rise in peak nocturnal GH, greatest with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment versus placebo groups. By 12 months stair climb also improved (P=0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance.

Participants / model
395 men and women aged 65 to 84 with mild functional limitation
Treatment
Oral capromorelin in four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night, 10 mg twice a day) or placebo
Follow-up
Intended 2 years; terminated early; 315 completed 6 months and 284 completed 12 months
Study design
Randomized, double-masked, placebo-controlled multicenter trial
Funding
not stated in the source

Stopped early according to predetermined treatment effect criteria. The population is older adults with mild functional limitation, not healthy or trained people.

Read the original source
Phase 1: spinal cord injured and able-bodied volunteers, single doses, no serious adverse events

Clinical trial

Ellis AG et al. Spinal Cord. 2015;53(2):103-8. PMID 25448190.

No serious adverse events were recorded in either group, there were no abnormal blood pressure or heart rate changes, and minor adverse events resolved quickly. Both groups showed dose-dependent increases in Cmax and AUC. The spinal cord injured participants showed greater variance in pharmacokinetic parameters and a slightly delayed Tmax and half-life. The published abstract gives no numeric pharmacokinetic values.

Participants / model
Spinal cord injured and able-bodied adult volunteers; number not stated in the source
Treatment
Oral capromorelin, 20, 50 and then 100 mg, at least 1 week apart
Follow-up
Single doses with 12 hours of PK sampling and 1-week and 4-week safety follow-up
Study design
Single-center single ascending dose phase 1 trial
Funding
not stated in the source

The abstract gives no numeric Cmax, AUC, Tmax or half-life, so none are carried onto this page.

Read the original source

What did the dog and cat approval studies find?

In 177 dogs with reduced appetite, owner-scored success was 68.6% (n=83) with ENTYCE versus 44.6% (n=25) with vehicle over 4 days. In cats with chronic kidney disease, body weight changed by +5.2% versus -1.6% on vehicle from day 0 to day 55. The endpoints were appetite and body weight, not muscle.

The ENTYCE label reports a laboratory study in 24 healthy Beagles with normal appetite: food consumption rose significantly over 4 days with capromorelin versus vehicle control (p<0.001). In the clinical field study, 177 dogs were evaluated (121 on ENTYCE, 56 on vehicle control). They were aged 4 months to 18 years with reduced or absent appetite for at least 2 days and were treated for 4 days. Owner-scored treatment success was 68.6% (n=83) with ENTYCE versus 44.6% (n=25) with vehicle control (p=0.0078). The endpoint is an owner appetite score at day 3, not muscle mass.

The ELURA label reports a multicenter, masked, randomized, vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg), treated for 56 days. In the 112 cats in the effectiveness analysis, body weight changed by +5.2% with ELURA versus -1.6% with vehicle control from day 0 to day 55 (p<0.0001). Least squares mean differences were +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. The endpoint is body weight, not lean mass.

Both are veterinary products tested in animals with a documented appetite or weight problem. They show that the compound stimulates appetite and weight gain in those species. They do not show that it preserves muscle in people.

ENTYCE dog label, version effective 19 November 2025: approval, field studies, PK, safety

Official label

DailyMed, U.S. National Library of Medicine. ENTYCE (capromorelin oral solution) for dogs, FDA-approved animal drug label under NADA 141-457, label version effective 19 November 2025. Set ID 0a403b74-72be-4f90-a069-d747caea1247.

ENTYCE is FDA-approved under NADA 141-457 for appetite stimulation in dogs. The label describes a selective ghrelin receptor agonist that binds receptors in the hypothalamus to stimulate appetite and the growth hormone secretagogue receptor in the pituitary to increase growth hormone secretion. It states that effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study, that the product is not for use in humans, and that it may be dermally absorbed. In 24 healthy Beagles, food consumption rose significantly over 4 days (p<0.001). In a clinical field study of 177 dogs (121 ENTYCE, 56 vehicle control) with reduced or absent appetite for at least 2 days, owner-scored treatment success was 68.6% (n=83) versus 44.6% (n=25), p=0.0078. In 12 Beagles after an oral dose, mean Tmax was 0.83 hours, mean Cmax 330 ng/mL, mean AUCt 655 ng.hr/mL, mean AUCinf 695 ng.hr/mL and mean terminal half-life 1.19 hours, with mean absolute oral bioavailability of 44%, mean total plasma clearance of 18.9 mL/min/kg, volume of distribution of 2.0 L/kg and unbound plasma fraction of 51%. Metabolism is mainly CYP3A4 and CYP3A5; excretion within 72 hours was 37% urine and 62% feces. In a controlled field study of 244 dogs (171 ENTYCE, 73 vehicle control), diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in all groups given capromorelin, with increased liver weights and hepatocellular cytoplasmic vacuolation, and decreased red blood cell count, hemoglobin and hematocrit at 40 mg/kg.

Participants / model
Dogs: 24 healthy Beagles, 177 dogs in the effectiveness field study, 244 dogs in the controlled field study, 12 Beagles for pharmacokinetics, 32 healthy Beagles in the 12-month study
Treatment
ENTYCE capromorelin oral solution, by mouth
Follow-up
Label version effective 19 November 2025; field studies of 4 days; laboratory study of 12 months
Study design
Official FDA animal drug label
Funding
not stated in the source

These are dog numbers and do not transfer to people. The label states the product is not for use in humans.

Read the original source
ELURA cat label, version effective 11 November 2025: approval, field study, safety

Official label

DailyMed, U.S. National Library of Medicine. ELURA (capromorelin oral solution) for cats, FDA-approved animal drug label under NADA 141-536, label version effective 11 November 2025. Set ID be4beb9c-f39b-4b23-9c35-f72a049a3250.

ELURA is FDA-approved under NADA 141-536 for management of weight loss in cats with chronic kidney disease. The label says it binds receptors in the hypothalamus to stimulate appetite and in the pituitary to stimulate GH secretion, that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH but that this is unknown in cats. It is not for use in cats with hypersomatotropism (acromegaly), may increase serum glucose for several hours after dosing, and causes transient decreases in heart rate and blood pressure up to 4 hours after dosing. In a multicenter masked randomized vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg) treated for 56 days, percent change in body weight from day 0 to day 55 in the 112 cats in the effectiveness analysis was +5.2% with ELURA versus -1.6% with vehicle control, p<0.0001, with least squares mean differences of +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. In the field study (118 ELURA, 58 vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation 21.2% versus 0.0%, inappetence 18.6% versus 12.0%, behavior change 14.4% versus 5.2%, anemia 9.3% versus 1.7%, CKD stage increased 8.5% versus 5.2% and hyperglycemia 6.8% versus 3.4%, with diabetes mellitus in 1 cat and congestive heart failure in 1 cat. Nine cats (8 ELURA, 1 vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. In a 32-day telemetry study in 8 healthy juvenile male cats, heart rate and blood pressure fell transiently with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic), returning to baseline within 4 hours; blood glucose rose in 4 cats, with one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 10.5 mg/kg was euthanized for diabetic ketoacidosis.

Participants / model
Cats: 176 client-owned cats with chronic kidney disease in the field study; 8 healthy juvenile male cats in the telemetry study; 32 healthy cats in the 6-month study
Treatment
ELURA capromorelin oral solution, by mouth
Follow-up
Label version effective 11 November 2025; field study of 56 days; telemetry study of 32 days; margin-of-safety study of 6 months
Study design
Official FDA animal drug label
Funding
not stated in the source

The endpoint is body weight, not lean mass. These are cat numbers and do not transfer to people.

Read the original source

Is capromorelin an oral substitute for injectable growth hormone peptides?

No study supports that. A PubMed search on 9 October 2026 for capromorelin with injectable growth hormone releasing peptides returned 3 records, and none compared capromorelin with an injectable peptide in people or measured muscle mass in people.

Sellers say capromorelin raises GH and IGF-1, stimulates appetite and preserves muscle, and gives pulsatile GH without injections as an oral substitute for injectable growth hormone releasing peptides. The claim is partly supported. GH and IGF-1 elevation is documented in dogs, cats and older adults. Appetite stimulation is the approved indication in dogs. Muscle preservation has one human result, 1.4 kg of lean body mass at 6 months in adults aged 65 to 84.

The PubMed search paired capromorelin with GHRP-2, GHRP-6, ipamorelin, hexarelin, pralmorelin or growth hormone releasing peptide. It returned a mouse gastric-emptying comparison of ghrelin, GHRP-6 and capromorelin, the Pfizer preclinical pharmacology report, and a rabbit cardiac ischemia study. A ClinicalTrials.gov term search for capromorelin returned 0 records, and an openFDA Drugs@FDA substance-name query returned no matching human drug application.

The word pulsatile in the claim traces to rat and dog experiments, in which acute administration to anesthetized rats or conscious dogs induced pulsatile GH release in a dose-dependent manner. It does not trace to a human study.

Searches, 9 October 2026: no human comparison with injectable peptides, no human application

PubMed search record

PubMed search run on 9 October 2026: capromorelin AND (GHRP-2 OR GHRP-6 OR ipamorelin OR hexarelin OR pralmorelin OR growth hormone releasing peptide), 3 records. ClinicalTrials.gov term search for capromorelin and openFDA Drugs@FDA substance-name query for capromorelin, same day.

The PubMed search returned 3 records: a mouse gastric-emptying comparison of ghrelin, GHRP-6 and capromorelin, the Pfizer preclinical pharmacology report, and a rabbit cardiac ischemia study. None compared capromorelin with an injectable GHRP in people, and none measured muscle mass in people. A ClinicalTrials.gov term search for capromorelin returned 0 records, and an openFDA Drugs@FDA substance-name query for capromorelin returned no matching human drug application. The compound's only approvals are the two veterinary NADAs.

Participants / model
Records returned, not a population
Treatment
Not applicable
Follow-up
Searches run on 9 October 2026
Study design
Literature, registry and regulator searches
Funding
not stated in the source

A search result shows what the databases returned on that date. It is not proof that no unindexed study exists.

Read the original source
Older adults: 395 randomized, stopped early, lean body mass +1.4 versus +0.3 kg at 6 months

Randomized controlled trial

White HK et al. J Clin Endocrinol Metab. 2009;94(4):1198-206. PMID 19174493.

A sustained dose-related rise in IGF-1 occurred in all active groups, and each dose produced a rise in peak nocturnal GH, greatest with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment versus placebo groups. By 12 months stair climb also improved (P=0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance.

Participants / model
395 men and women aged 65 to 84 with mild functional limitation
Treatment
Oral capromorelin in four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night, 10 mg twice a day) or placebo
Follow-up
Intended 2 years; terminated early; 315 completed 6 months and 284 completed 12 months
Study design
Randomized, double-masked, placebo-controlled multicenter trial
Funding
not stated in the source

Stopped early according to predetermined treatment effect criteria. The population is older adults with mild functional limitation, not healthy or trained people.

Read the original source
Preclinical: rat pituitary cells EC50 3 nM; pulsatile GH release in rats and dogs

Animal study

Pan LC et al. Endocrine. 2001;14(1):121-32. PMID 11322494.

CP-424,391 (capromorelin) stimulated GH release from rat pituitary cell cultures with an EC50 of 3 nM, activated intracellular calcium signaling without raising cAMP, and required expression of the recombinant human GHS receptor to signal in nonpituitary cell lines. Acute administration to anesthetized rats or conscious dogs induced pulsatile GH release in a dose-dependent manner. Plasma IGF-1 rose progressively over a 5-day course of daily oral dosing in dogs, and chronic oral administration augmented body weight gain in rats and dogs.

Participants / model
Rat pituitary cells, nonpituitary cell lines, anesthetized rats and conscious dogs
Treatment
Capromorelin by oral and acute administration; doses not stated in the source
Follow-up
Acute dosing; 5-day oral course in dogs
Study design
Preclinical pharmacology study
Funding
not stated in the source

The word pulsatile in the supplier claim traces to this rat and dog work, not to a human study.

Read the original source

Does the growth hormone response last with repeated dosing?

In 6 beagles dosed for 7 days, the GH rise was smaller on days 4 and 7 than on day 1, while the IGF-1 rise was sustained through day 7. Cortisol also rose after dosing, with a smaller rise on days 4 and 7.

In 6 healthy adult beagles given placebo twice daily, 3.0 mg/kg once daily, 4.5 mg/kg once daily or 3.0 mg/kg twice daily for 7 days, capromorelin increased food consumption and body weight versus placebo and raised serum GH, which returned to baseline by 8 hours after dosing. The GH increase was smaller on days 4 and 7 than on day 1. IGF-1 rose on day 1 and the increase was sustained through day 7. Serum cortisol rose after dosing and returned to baseline by 8 hours, again with a smaller increase on days 4 and 7.

The authors propose that sustained IGF-1 may increase lean muscle mass over extended periods, which they did not measure. This is a dog study. In the human trial in older adults, the peak nocturnal GH rise was greatest with the least frequent dosing.

Beagles: 6 dogs, 7 days, GH rise smaller on days 4 and 7, IGF-1 sustained

Animal study

Zollers B et al. J Vet Pharmacol Ther. 2017;40(2):140-147. PMID 27597271.

Capromorelin increased food consumption and body weight versus placebo and raised serum GH, which returned to baseline by 8 hours after dosing. The magnitude of the GH increase was less on days 4 and 7 than on day 1. IGF-1 rose on day 1 and the increase was sustained through day 7. Serum cortisol also rose after dosing and returned to baseline by 8 hours, again with a smaller increase on days 4 and 7. The authors propose that sustained IGF-1 may increase lean muscle mass over extended periods, which they did not measure.

Participants / model
6 healthy adult Beagle dogs
Treatment
Oral capromorelin: placebo twice daily, 3.0 mg/kg once daily, 4.5 mg/kg once daily or 3.0 mg/kg twice daily
Follow-up
7 days
Study design
Controlled animal study
Funding
not stated in the source

This is a dog study. The GH response shrank on repeat dosing while IGF-1 did not.

Read the original source
Older adults: 395 randomized, stopped early, lean body mass +1.4 versus +0.3 kg at 6 months

Randomized controlled trial

White HK et al. J Clin Endocrinol Metab. 2009;94(4):1198-206. PMID 19174493.

A sustained dose-related rise in IGF-1 occurred in all active groups, and each dose produced a rise in peak nocturnal GH, greatest with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment versus placebo groups. By 12 months stair climb also improved (P=0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance.

Participants / model
395 men and women aged 65 to 84 with mild functional limitation
Treatment
Oral capromorelin in four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night, 10 mg twice a day) or placebo
Follow-up
Intended 2 years; terminated early; 315 completed 6 months and 284 completed 12 months
Study design
Randomized, double-masked, placebo-controlled multicenter trial
Funding
not stated in the source

Stopped early according to predetermined treatment effect criteria. The population is older adults with mild functional limitation, not healthy or trained people.

Read the original source

How does capromorelin work, and what happens to it in the body?

Capromorelin is a selective ghrelin receptor agonist. The veterinary labels say it acts on the hypothalamus to stimulate appetite and on the pituitary to increase GH secretion. In 12 beagles after an oral dose, mean Tmax was 0.83 hours and mean terminal half-life 1.19 hours; no numeric human values are available.

CP-424,391 (capromorelin) stimulated GH release from rat pituitary cell cultures with an EC50 of 3 nM and activated intracellular calcium signaling without raising cAMP. In nonpituitary cell lines it needed expression of the recombinant human GHS receptor to signal. Plasma IGF-1 rose progressively over a 5-day course of daily oral dosing in dogs, and chronic oral administration augmented body weight gain in rats and dogs.

The ELURA label says that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH, but that this is unknown in cats.

In 12 beagle dogs after an oral dose, the ENTYCE label gives a mean Tmax of 0.83 hours, mean Cmax of 330 ng/mL, mean AUCt of 655 ng.hr/mL, mean AUCinf of 695 ng.hr/mL and a mean terminal half-life of 1.19 hours. Mean absolute oral bioavailability was 44%, mean total plasma clearance 18.9 mL/min/kg, volume of distribution 2.0 L/kg and unbound plasma fraction 51%. Metabolism is mainly by CYP3A4 and CYP3A5, and excretion within 72 hours was 37% in urine and 62% in feces. Exposure rose with dose but not dose-proportionally, and there was no accumulation on repeat daily dosing. These are dog numbers and do not transfer to people.

In the human phase 1 study, Cmax and AUC rose with dose in both groups, but the abstract gives no numeric values, so no human pharmacokinetic figures are given here.

Preclinical: rat pituitary cells EC50 3 nM; pulsatile GH release in rats and dogs

Animal study

Pan LC et al. Endocrine. 2001;14(1):121-32. PMID 11322494.

CP-424,391 (capromorelin) stimulated GH release from rat pituitary cell cultures with an EC50 of 3 nM, activated intracellular calcium signaling without raising cAMP, and required expression of the recombinant human GHS receptor to signal in nonpituitary cell lines. Acute administration to anesthetized rats or conscious dogs induced pulsatile GH release in a dose-dependent manner. Plasma IGF-1 rose progressively over a 5-day course of daily oral dosing in dogs, and chronic oral administration augmented body weight gain in rats and dogs.

Participants / model
Rat pituitary cells, nonpituitary cell lines, anesthetized rats and conscious dogs
Treatment
Capromorelin by oral and acute administration; doses not stated in the source
Follow-up
Acute dosing; 5-day oral course in dogs
Study design
Preclinical pharmacology study
Funding
not stated in the source

The word pulsatile in the supplier claim traces to this rat and dog work, not to a human study.

Read the original source
ELURA cat label, version effective 11 November 2025: approval, field study, safety

Official label

DailyMed, U.S. National Library of Medicine. ELURA (capromorelin oral solution) for cats, FDA-approved animal drug label under NADA 141-536, label version effective 11 November 2025. Set ID be4beb9c-f39b-4b23-9c35-f72a049a3250.

ELURA is FDA-approved under NADA 141-536 for management of weight loss in cats with chronic kidney disease. The label says it binds receptors in the hypothalamus to stimulate appetite and in the pituitary to stimulate GH secretion, that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH but that this is unknown in cats. It is not for use in cats with hypersomatotropism (acromegaly), may increase serum glucose for several hours after dosing, and causes transient decreases in heart rate and blood pressure up to 4 hours after dosing. In a multicenter masked randomized vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg) treated for 56 days, percent change in body weight from day 0 to day 55 in the 112 cats in the effectiveness analysis was +5.2% with ELURA versus -1.6% with vehicle control, p<0.0001, with least squares mean differences of +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. In the field study (118 ELURA, 58 vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation 21.2% versus 0.0%, inappetence 18.6% versus 12.0%, behavior change 14.4% versus 5.2%, anemia 9.3% versus 1.7%, CKD stage increased 8.5% versus 5.2% and hyperglycemia 6.8% versus 3.4%, with diabetes mellitus in 1 cat and congestive heart failure in 1 cat. Nine cats (8 ELURA, 1 vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. In a 32-day telemetry study in 8 healthy juvenile male cats, heart rate and blood pressure fell transiently with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic), returning to baseline within 4 hours; blood glucose rose in 4 cats, with one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 10.5 mg/kg was euthanized for diabetic ketoacidosis.

Participants / model
Cats: 176 client-owned cats with chronic kidney disease in the field study; 8 healthy juvenile male cats in the telemetry study; 32 healthy cats in the 6-month study
Treatment
ELURA capromorelin oral solution, by mouth
Follow-up
Label version effective 11 November 2025; field study of 56 days; telemetry study of 32 days; margin-of-safety study of 6 months
Study design
Official FDA animal drug label
Funding
not stated in the source

The endpoint is body weight, not lean mass. These are cat numbers and do not transfer to people.

Read the original source
ENTYCE dog label, version effective 19 November 2025: approval, field studies, PK, safety

Official label

DailyMed, U.S. National Library of Medicine. ENTYCE (capromorelin oral solution) for dogs, FDA-approved animal drug label under NADA 141-457, label version effective 19 November 2025. Set ID 0a403b74-72be-4f90-a069-d747caea1247.

ENTYCE is FDA-approved under NADA 141-457 for appetite stimulation in dogs. The label describes a selective ghrelin receptor agonist that binds receptors in the hypothalamus to stimulate appetite and the growth hormone secretagogue receptor in the pituitary to increase growth hormone secretion. It states that effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study, that the product is not for use in humans, and that it may be dermally absorbed. In 24 healthy Beagles, food consumption rose significantly over 4 days (p<0.001). In a clinical field study of 177 dogs (121 ENTYCE, 56 vehicle control) with reduced or absent appetite for at least 2 days, owner-scored treatment success was 68.6% (n=83) versus 44.6% (n=25), p=0.0078. In 12 Beagles after an oral dose, mean Tmax was 0.83 hours, mean Cmax 330 ng/mL, mean AUCt 655 ng.hr/mL, mean AUCinf 695 ng.hr/mL and mean terminal half-life 1.19 hours, with mean absolute oral bioavailability of 44%, mean total plasma clearance of 18.9 mL/min/kg, volume of distribution of 2.0 L/kg and unbound plasma fraction of 51%. Metabolism is mainly CYP3A4 and CYP3A5; excretion within 72 hours was 37% urine and 62% feces. In a controlled field study of 244 dogs (171 ENTYCE, 73 vehicle control), diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in all groups given capromorelin, with increased liver weights and hepatocellular cytoplasmic vacuolation, and decreased red blood cell count, hemoglobin and hematocrit at 40 mg/kg.

Participants / model
Dogs: 24 healthy Beagles, 177 dogs in the effectiveness field study, 244 dogs in the controlled field study, 12 Beagles for pharmacokinetics, 32 healthy Beagles in the 12-month study
Treatment
ENTYCE capromorelin oral solution, by mouth
Follow-up
Label version effective 19 November 2025; field studies of 4 days; laboratory study of 12 months
Study design
Official FDA animal drug label
Funding
not stated in the source

These are dog numbers and do not transfer to people. The label states the product is not for use in humans.

Read the original source
Phase 1: spinal cord injured and able-bodied volunteers, single doses, no serious adverse events

Clinical trial

Ellis AG et al. Spinal Cord. 2015;53(2):103-8. PMID 25448190.

No serious adverse events were recorded in either group, there were no abnormal blood pressure or heart rate changes, and minor adverse events resolved quickly. Both groups showed dose-dependent increases in Cmax and AUC. The spinal cord injured participants showed greater variance in pharmacokinetic parameters and a slightly delayed Tmax and half-life. The published abstract gives no numeric pharmacokinetic values.

Participants / model
Spinal cord injured and able-bodied adult volunteers; number not stated in the source
Treatment
Oral capromorelin, 20, 50 and then 100 mg, at least 1 week apart
Follow-up
Single doses with 12 hours of PK sampling and 1-week and 4-week safety follow-up
Study design
Single-center single ascending dose phase 1 trial
Funding
not stated in the source

The abstract gives no numeric Cmax, AUC, Tmax or half-life, so none are carried onto this page.

Read the original source

What safety warnings and adverse effects have been reported?

The dog label states ENTYCE is not for use in humans. The 395-person human trial reported fatigue, insomnia and small rises in fasting glucose, glycosylated hemoglobin and insulin resistance indices. Animal labels add hyperglycemia, transient falls in heart rate and blood pressure, and liver and red cell findings at high doses.

In the 395-person trial, adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance. No serious adverse events were recorded in the single-dose phase 1 study.

In the controlled ENTYCE field study, 244 dogs were evaluated (171 on ENTYCE, 73 on vehicle control). Diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. The label warns that the product may be dermally absorbed and tells users to consult a physician after accidental ingestion by humans.

In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in every group given capromorelin. Liver weights and hepatocellular cytoplasmic vacuolation increased, and red blood cell count, hemoglobin and hematocrit decreased at 40 mg/kg.

In the 56-day ELURA field study (118 cats on ELURA, 58 on vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation in 21.2% versus 0.0%, inappetence in 18.6% versus 12.0%, behavior change in 14.4% versus 5.2%, anemia in 9.3% versus 1.7%, increased CKD stage in 8.5% versus 5.2% and hyperglycemia in 6.8% versus 3.4%. Diabetes mellitus was reported in 1 cat and congestive heart failure in 1 cat. Nine cats (8 on ELURA, 1 on vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. The label states ELURA is not for use in cats with hypersomatotropism (acromegaly).

The glucose signal needs its own line. The cat label says ELURA may increase serum glucose for several hours after dosing. In a 32-day telemetry study in 8 healthy juvenile male cats at the labeled dose, heart rate and blood pressure fell transiently, with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic) and a return to baseline within 4 hours. Blood glucose rose in 4 cats, one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 5 times the labeled dose (10.5 mg/kg) was euthanized for diabetic ketoacidosis. Hyperglycemia also appears in the post-approval dog reports, and the human trial recorded small rises in fasting glucose, glycosylated hemoglobin and insulin resistance indices.

Older adults: 395 randomized, stopped early, lean body mass +1.4 versus +0.3 kg at 6 months

Randomized controlled trial

White HK et al. J Clin Endocrinol Metab. 2009;94(4):1198-206. PMID 19174493.

A sustained dose-related rise in IGF-1 occurred in all active groups, and each dose produced a rise in peak nocturnal GH, greatest with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment versus placebo groups. By 12 months stair climb also improved (P=0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance.

Participants / model
395 men and women aged 65 to 84 with mild functional limitation
Treatment
Oral capromorelin in four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night, 10 mg twice a day) or placebo
Follow-up
Intended 2 years; terminated early; 315 completed 6 months and 284 completed 12 months
Study design
Randomized, double-masked, placebo-controlled multicenter trial
Funding
not stated in the source

Stopped early according to predetermined treatment effect criteria. The population is older adults with mild functional limitation, not healthy or trained people.

Read the original source
Phase 1: spinal cord injured and able-bodied volunteers, single doses, no serious adverse events

Clinical trial

Ellis AG et al. Spinal Cord. 2015;53(2):103-8. PMID 25448190.

No serious adverse events were recorded in either group, there were no abnormal blood pressure or heart rate changes, and minor adverse events resolved quickly. Both groups showed dose-dependent increases in Cmax and AUC. The spinal cord injured participants showed greater variance in pharmacokinetic parameters and a slightly delayed Tmax and half-life. The published abstract gives no numeric pharmacokinetic values.

Participants / model
Spinal cord injured and able-bodied adult volunteers; number not stated in the source
Treatment
Oral capromorelin, 20, 50 and then 100 mg, at least 1 week apart
Follow-up
Single doses with 12 hours of PK sampling and 1-week and 4-week safety follow-up
Study design
Single-center single ascending dose phase 1 trial
Funding
not stated in the source

The abstract gives no numeric Cmax, AUC, Tmax or half-life, so none are carried onto this page.

Read the original source
ENTYCE dog label, version effective 19 November 2025: approval, field studies, PK, safety

Official label

DailyMed, U.S. National Library of Medicine. ENTYCE (capromorelin oral solution) for dogs, FDA-approved animal drug label under NADA 141-457, label version effective 19 November 2025. Set ID 0a403b74-72be-4f90-a069-d747caea1247.

ENTYCE is FDA-approved under NADA 141-457 for appetite stimulation in dogs. The label describes a selective ghrelin receptor agonist that binds receptors in the hypothalamus to stimulate appetite and the growth hormone secretagogue receptor in the pituitary to increase growth hormone secretion. It states that effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study, that the product is not for use in humans, and that it may be dermally absorbed. In 24 healthy Beagles, food consumption rose significantly over 4 days (p<0.001). In a clinical field study of 177 dogs (121 ENTYCE, 56 vehicle control) with reduced or absent appetite for at least 2 days, owner-scored treatment success was 68.6% (n=83) versus 44.6% (n=25), p=0.0078. In 12 Beagles after an oral dose, mean Tmax was 0.83 hours, mean Cmax 330 ng/mL, mean AUCt 655 ng.hr/mL, mean AUCinf 695 ng.hr/mL and mean terminal half-life 1.19 hours, with mean absolute oral bioavailability of 44%, mean total plasma clearance of 18.9 mL/min/kg, volume of distribution of 2.0 L/kg and unbound plasma fraction of 51%. Metabolism is mainly CYP3A4 and CYP3A5; excretion within 72 hours was 37% urine and 62% feces. In a controlled field study of 244 dogs (171 ENTYCE, 73 vehicle control), diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in all groups given capromorelin, with increased liver weights and hepatocellular cytoplasmic vacuolation, and decreased red blood cell count, hemoglobin and hematocrit at 40 mg/kg.

Participants / model
Dogs: 24 healthy Beagles, 177 dogs in the effectiveness field study, 244 dogs in the controlled field study, 12 Beagles for pharmacokinetics, 32 healthy Beagles in the 12-month study
Treatment
ENTYCE capromorelin oral solution, by mouth
Follow-up
Label version effective 19 November 2025; field studies of 4 days; laboratory study of 12 months
Study design
Official FDA animal drug label
Funding
not stated in the source

These are dog numbers and do not transfer to people. The label states the product is not for use in humans.

Read the original source
ELURA cat label, version effective 11 November 2025: approval, field study, safety

Official label

DailyMed, U.S. National Library of Medicine. ELURA (capromorelin oral solution) for cats, FDA-approved animal drug label under NADA 141-536, label version effective 11 November 2025. Set ID be4beb9c-f39b-4b23-9c35-f72a049a3250.

ELURA is FDA-approved under NADA 141-536 for management of weight loss in cats with chronic kidney disease. The label says it binds receptors in the hypothalamus to stimulate appetite and in the pituitary to stimulate GH secretion, that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH but that this is unknown in cats. It is not for use in cats with hypersomatotropism (acromegaly), may increase serum glucose for several hours after dosing, and causes transient decreases in heart rate and blood pressure up to 4 hours after dosing. In a multicenter masked randomized vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg) treated for 56 days, percent change in body weight from day 0 to day 55 in the 112 cats in the effectiveness analysis was +5.2% with ELURA versus -1.6% with vehicle control, p<0.0001, with least squares mean differences of +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. In the field study (118 ELURA, 58 vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation 21.2% versus 0.0%, inappetence 18.6% versus 12.0%, behavior change 14.4% versus 5.2%, anemia 9.3% versus 1.7%, CKD stage increased 8.5% versus 5.2% and hyperglycemia 6.8% versus 3.4%, with diabetes mellitus in 1 cat and congestive heart failure in 1 cat. Nine cats (8 ELURA, 1 vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. In a 32-day telemetry study in 8 healthy juvenile male cats, heart rate and blood pressure fell transiently with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic), returning to baseline within 4 hours; blood glucose rose in 4 cats, with one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 10.5 mg/kg was euthanized for diabetic ketoacidosis.

Participants / model
Cats: 176 client-owned cats with chronic kidney disease in the field study; 8 healthy juvenile male cats in the telemetry study; 32 healthy cats in the 6-month study
Treatment
ELURA capromorelin oral solution, by mouth
Follow-up
Label version effective 11 November 2025; field study of 56 days; telemetry study of 32 days; margin-of-safety study of 6 months
Study design
Official FDA animal drug label
Funding
not stated in the source

The endpoint is body weight, not lean mass. These are cat numbers and do not transfer to people.

Read the original source

Why does capromorelin sit in C tier?

The mechanism is established and two veterinary approvals rest on randomized field studies, but the human file is one 395-person trial stopped early and one phase 1 study. That is a plausible mechanism with thin human outcome data.

Capromorelin raises GH in rat pituitary cells, rats, dogs and older adults, and raises IGF-1 in dogs, cats and older adults. Two FDA veterinary approvals rest on randomized vehicle-controlled field studies with real endpoints: 68.6% versus 44.6% appetite success in 177 dogs, and +5.2% versus -1.6% body weight in 112 cats.

The human file is one 395-person randomized trial that was stopped early under a predetermined treatment effect rule, plus one single-dose phase 1 study, with nothing since: no ClinicalTrials.gov records and no human drug application on 9 October 2026.

The supplier claim is partly supported. The oral-substitute framing has no head-to-head human study behind it in the records reviewed on 9 October 2026, and the muscle result is limited to adults aged 65 to 84. The dog data also show the GH response shrinking by day 4 and day 7 of daily dosing, and a glucose signal runs through the human, dog and cat records.

Older adults: 395 randomized, stopped early, lean body mass +1.4 versus +0.3 kg at 6 months

Randomized controlled trial

White HK et al. J Clin Endocrinol Metab. 2009;94(4):1198-206. PMID 19174493.

A sustained dose-related rise in IGF-1 occurred in all active groups, and each dose produced a rise in peak nocturnal GH, greatest with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment versus placebo groups. By 12 months stair climb also improved (P=0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance.

Participants / model
395 men and women aged 65 to 84 with mild functional limitation
Treatment
Oral capromorelin in four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night, 10 mg twice a day) or placebo
Follow-up
Intended 2 years; terminated early; 315 completed 6 months and 284 completed 12 months
Study design
Randomized, double-masked, placebo-controlled multicenter trial
Funding
not stated in the source

Stopped early according to predetermined treatment effect criteria. The population is older adults with mild functional limitation, not healthy or trained people.

Read the original source
Phase 1: spinal cord injured and able-bodied volunteers, single doses, no serious adverse events

Clinical trial

Ellis AG et al. Spinal Cord. 2015;53(2):103-8. PMID 25448190.

No serious adverse events were recorded in either group, there were no abnormal blood pressure or heart rate changes, and minor adverse events resolved quickly. Both groups showed dose-dependent increases in Cmax and AUC. The spinal cord injured participants showed greater variance in pharmacokinetic parameters and a slightly delayed Tmax and half-life. The published abstract gives no numeric pharmacokinetic values.

Participants / model
Spinal cord injured and able-bodied adult volunteers; number not stated in the source
Treatment
Oral capromorelin, 20, 50 and then 100 mg, at least 1 week apart
Follow-up
Single doses with 12 hours of PK sampling and 1-week and 4-week safety follow-up
Study design
Single-center single ascending dose phase 1 trial
Funding
not stated in the source

The abstract gives no numeric Cmax, AUC, Tmax or half-life, so none are carried onto this page.

Read the original source
ENTYCE dog label, version effective 19 November 2025: approval, field studies, PK, safety

Official label

DailyMed, U.S. National Library of Medicine. ENTYCE (capromorelin oral solution) for dogs, FDA-approved animal drug label under NADA 141-457, label version effective 19 November 2025. Set ID 0a403b74-72be-4f90-a069-d747caea1247.

ENTYCE is FDA-approved under NADA 141-457 for appetite stimulation in dogs. The label describes a selective ghrelin receptor agonist that binds receptors in the hypothalamus to stimulate appetite and the growth hormone secretagogue receptor in the pituitary to increase growth hormone secretion. It states that effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study, that the product is not for use in humans, and that it may be dermally absorbed. In 24 healthy Beagles, food consumption rose significantly over 4 days (p<0.001). In a clinical field study of 177 dogs (121 ENTYCE, 56 vehicle control) with reduced or absent appetite for at least 2 days, owner-scored treatment success was 68.6% (n=83) versus 44.6% (n=25), p=0.0078. In 12 Beagles after an oral dose, mean Tmax was 0.83 hours, mean Cmax 330 ng/mL, mean AUCt 655 ng.hr/mL, mean AUCinf 695 ng.hr/mL and mean terminal half-life 1.19 hours, with mean absolute oral bioavailability of 44%, mean total plasma clearance of 18.9 mL/min/kg, volume of distribution of 2.0 L/kg and unbound plasma fraction of 51%. Metabolism is mainly CYP3A4 and CYP3A5; excretion within 72 hours was 37% urine and 62% feces. In a controlled field study of 244 dogs (171 ENTYCE, 73 vehicle control), diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in all groups given capromorelin, with increased liver weights and hepatocellular cytoplasmic vacuolation, and decreased red blood cell count, hemoglobin and hematocrit at 40 mg/kg.

Participants / model
Dogs: 24 healthy Beagles, 177 dogs in the effectiveness field study, 244 dogs in the controlled field study, 12 Beagles for pharmacokinetics, 32 healthy Beagles in the 12-month study
Treatment
ENTYCE capromorelin oral solution, by mouth
Follow-up
Label version effective 19 November 2025; field studies of 4 days; laboratory study of 12 months
Study design
Official FDA animal drug label
Funding
not stated in the source

These are dog numbers and do not transfer to people. The label states the product is not for use in humans.

Read the original source
ELURA cat label, version effective 11 November 2025: approval, field study, safety

Official label

DailyMed, U.S. National Library of Medicine. ELURA (capromorelin oral solution) for cats, FDA-approved animal drug label under NADA 141-536, label version effective 11 November 2025. Set ID be4beb9c-f39b-4b23-9c35-f72a049a3250.

ELURA is FDA-approved under NADA 141-536 for management of weight loss in cats with chronic kidney disease. The label says it binds receptors in the hypothalamus to stimulate appetite and in the pituitary to stimulate GH secretion, that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH but that this is unknown in cats. It is not for use in cats with hypersomatotropism (acromegaly), may increase serum glucose for several hours after dosing, and causes transient decreases in heart rate and blood pressure up to 4 hours after dosing. In a multicenter masked randomized vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg) treated for 56 days, percent change in body weight from day 0 to day 55 in the 112 cats in the effectiveness analysis was +5.2% with ELURA versus -1.6% with vehicle control, p<0.0001, with least squares mean differences of +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. In the field study (118 ELURA, 58 vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation 21.2% versus 0.0%, inappetence 18.6% versus 12.0%, behavior change 14.4% versus 5.2%, anemia 9.3% versus 1.7%, CKD stage increased 8.5% versus 5.2% and hyperglycemia 6.8% versus 3.4%, with diabetes mellitus in 1 cat and congestive heart failure in 1 cat. Nine cats (8 ELURA, 1 vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. In a 32-day telemetry study in 8 healthy juvenile male cats, heart rate and blood pressure fell transiently with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic), returning to baseline within 4 hours; blood glucose rose in 4 cats, with one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 10.5 mg/kg was euthanized for diabetic ketoacidosis.

Participants / model
Cats: 176 client-owned cats with chronic kidney disease in the field study; 8 healthy juvenile male cats in the telemetry study; 32 healthy cats in the 6-month study
Treatment
ELURA capromorelin oral solution, by mouth
Follow-up
Label version effective 11 November 2025; field study of 56 days; telemetry study of 32 days; margin-of-safety study of 6 months
Study design
Official FDA animal drug label
Funding
not stated in the source

The endpoint is body weight, not lean mass. These are cat numbers and do not transfer to people.

Read the original source
Searches, 9 October 2026: no human comparison with injectable peptides, no human application

PubMed search record

PubMed search run on 9 October 2026: capromorelin AND (GHRP-2 OR GHRP-6 OR ipamorelin OR hexarelin OR pralmorelin OR growth hormone releasing peptide), 3 records. ClinicalTrials.gov term search for capromorelin and openFDA Drugs@FDA substance-name query for capromorelin, same day.

The PubMed search returned 3 records: a mouse gastric-emptying comparison of ghrelin, GHRP-6 and capromorelin, the Pfizer preclinical pharmacology report, and a rabbit cardiac ischemia study. None compared capromorelin with an injectable GHRP in people, and none measured muscle mass in people. A ClinicalTrials.gov term search for capromorelin returned 0 records, and an openFDA Drugs@FDA substance-name query for capromorelin returned no matching human drug application. The compound's only approvals are the two veterinary NADAs.

Participants / model
Records returned, not a population
Treatment
Not applicable
Follow-up
Searches run on 9 October 2026
Study design
Literature, registry and regulator searches
Funding
not stated in the source

A search result shows what the databases returned on that date. It is not proof that no unindexed study exists.

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Beagles: 6 dogs, 7 days, GH rise smaller on days 4 and 7, IGF-1 sustained

Animal study

Zollers B et al. J Vet Pharmacol Ther. 2017;40(2):140-147. PMID 27597271.

Capromorelin increased food consumption and body weight versus placebo and raised serum GH, which returned to baseline by 8 hours after dosing. The magnitude of the GH increase was less on days 4 and 7 than on day 1. IGF-1 rose on day 1 and the increase was sustained through day 7. Serum cortisol also rose after dosing and returned to baseline by 8 hours, again with a smaller increase on days 4 and 7. The authors propose that sustained IGF-1 may increase lean muscle mass over extended periods, which they did not measure.

Participants / model
6 healthy adult Beagle dogs
Treatment
Oral capromorelin: placebo twice daily, 3.0 mg/kg once daily, 4.5 mg/kg once daily or 3.0 mg/kg twice daily
Follow-up
7 days
Study design
Controlled animal study
Funding
not stated in the source

This is a dog study. The GH response shrank on repeat dosing while IGF-1 did not.

Read the original source

Studies and sources

PubChem: capromorelin base and tartrate identity

Chemical identity record

National Library of Medicine. PubChem compound record CID 216208 (capromorelin), with the tartrate salt at CID 9852610.

Capromorelin free base is PubChem CID 216208: C28H35N5O4, molecular weight 505.6, CAS 193273-66-4. The salt in both approved products is capromorelin tartrate: CID 9852610, C32H41N5O10, molecular weight 655.7, CAS 193273-69-7. Listed synonyms include CP-424391, Entyce and Elura. Both FDA labels give the empirical formula C28H35N5O4 and C4H6O6 with molecular weight 655.70, which is the tartrate.

Participants / model
Chemical identity, not a clinical population
Treatment
Defined molecule and tartrate salt
Follow-up
Not applicable
Study design
NLM chemical record
Funding
not stated in the source

Product strengths are expressed as capromorelin, so a vendor powder sold as capromorelin may be either the base or the tartrate, and the two differ by about 23% in mass.

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ENTYCE dog label, version effective 19 November 2025: approval, field studies, PK, safety

Official label

DailyMed, U.S. National Library of Medicine. ENTYCE (capromorelin oral solution) for dogs, FDA-approved animal drug label under NADA 141-457, label version effective 19 November 2025. Set ID 0a403b74-72be-4f90-a069-d747caea1247.

ENTYCE is FDA-approved under NADA 141-457 for appetite stimulation in dogs. The label describes a selective ghrelin receptor agonist that binds receptors in the hypothalamus to stimulate appetite and the growth hormone secretagogue receptor in the pituitary to increase growth hormone secretion. It states that effectiveness has not been evaluated beyond 4 days of treatment in the clinical field study, that the product is not for use in humans, and that it may be dermally absorbed. In 24 healthy Beagles, food consumption rose significantly over 4 days (p<0.001). In a clinical field study of 177 dogs (121 ENTYCE, 56 vehicle control) with reduced or absent appetite for at least 2 days, owner-scored treatment success was 68.6% (n=83) versus 44.6% (n=25), p=0.0078. In 12 Beagles after an oral dose, mean Tmax was 0.83 hours, mean Cmax 330 ng/mL, mean AUCt 655 ng.hr/mL, mean AUCinf 695 ng.hr/mL and mean terminal half-life 1.19 hours, with mean absolute oral bioavailability of 44%, mean total plasma clearance of 18.9 mL/min/kg, volume of distribution of 2.0 L/kg and unbound plasma fraction of 51%. Metabolism is mainly CYP3A4 and CYP3A5; excretion within 72 hours was 37% urine and 62% feces. In a controlled field study of 244 dogs (171 ENTYCE, 73 vehicle control), diarrhea occurred in 7.0% versus 6.8%, vomiting in 6.4% versus 5.5%, hypersalivation in 2.3% versus 0.0%, elevated blood urea nitrogen in 4.1% versus 2.7% and polydipsia in 4.1% versus 1.4%. Post-approval reports include bradycardia, hypotension, hyperglycemia, ataxia, loss of consciousness, disorientation, sedation, panting and dyspnea. In a 12-month study in 32 healthy Beagles at 0.3, 7 and 40 mg/kg/day, GH and IGF-1 plasma levels were increased in all groups given capromorelin, with increased liver weights and hepatocellular cytoplasmic vacuolation, and decreased red blood cell count, hemoglobin and hematocrit at 40 mg/kg.

Participants / model
Dogs: 24 healthy Beagles, 177 dogs in the effectiveness field study, 244 dogs in the controlled field study, 12 Beagles for pharmacokinetics, 32 healthy Beagles in the 12-month study
Treatment
ENTYCE capromorelin oral solution, by mouth
Follow-up
Label version effective 19 November 2025; field studies of 4 days; laboratory study of 12 months
Study design
Official FDA animal drug label
Funding
not stated in the source

These are dog numbers and do not transfer to people. The label states the product is not for use in humans.

Read the original source
ELURA cat label, version effective 11 November 2025: approval, field study, safety

Official label

DailyMed, U.S. National Library of Medicine. ELURA (capromorelin oral solution) for cats, FDA-approved animal drug label under NADA 141-536, label version effective 11 November 2025. Set ID be4beb9c-f39b-4b23-9c35-f72a049a3250.

ELURA is FDA-approved under NADA 141-536 for management of weight loss in cats with chronic kidney disease. The label says it binds receptors in the hypothalamus to stimulate appetite and in the pituitary to stimulate GH secretion, that increased GH stimulates release of IGF-1 from the liver, which in turn can stimulate weight gain, and that IGF-1 remains elevated during administration. It adds that in humans IGF-1 elevation may act as a negative feedback regulator of GH but that this is unknown in cats. It is not for use in cats with hypersomatotropism (acromegaly), may increase serum glucose for several hours after dosing, and causes transient decreases in heart rate and blood pressure up to 4 hours after dosing. In a multicenter masked randomized vehicle-controlled field study in 176 client-owned cats with chronic kidney disease and at least 5% unintended weight loss (mean age 15 years, weight 1.81 to 6.76 kg) treated for 56 days, percent change in body weight from day 0 to day 55 in the 112 cats in the effectiveness analysis was +5.2% with ELURA versus -1.6% with vehicle control, p<0.0001, with least squares mean differences of +3.3% at day 15, +4.7% at day 27 and +6.8% at day 55. In the field study (118 ELURA, 58 vehicle control), vomiting occurred in 29.6% versus 22.4%, hypersalivation 21.2% versus 0.0%, inappetence 18.6% versus 12.0%, behavior change 14.4% versus 5.2%, anemia 9.3% versus 1.7%, CKD stage increased 8.5% versus 5.2% and hyperglycemia 6.8% versus 3.4%, with diabetes mellitus in 1 cat and congestive heart failure in 1 cat. Nine cats (8 ELURA, 1 vehicle control) died or were euthanized during or shortly after the study, six of them from decompensated CKD. In a 32-day telemetry study in 8 healthy juvenile male cats, heart rate and blood pressure fell transiently with maximal suppression about 1 hour after dosing (lowest individual values 83 bpm and 72 mmHg systolic), returning to baseline within 4 hours; blood glucose rose in 4 cats, with one reaching 296 mg/dL, and serum IGF-1 was increased at day 32 versus baseline. In a 6-month study in 32 healthy cats, one cat at 10.5 mg/kg was euthanized for diabetic ketoacidosis.

Participants / model
Cats: 176 client-owned cats with chronic kidney disease in the field study; 8 healthy juvenile male cats in the telemetry study; 32 healthy cats in the 6-month study
Treatment
ELURA capromorelin oral solution, by mouth
Follow-up
Label version effective 11 November 2025; field study of 56 days; telemetry study of 32 days; margin-of-safety study of 6 months
Study design
Official FDA animal drug label
Funding
not stated in the source

The endpoint is body weight, not lean mass. These are cat numbers and do not transfer to people.

Read the original source
Federal Register: ENTYCE 2016 and ELURA 2020 veterinary approvals

Regulatory record

U.S. Food and Drug Administration. New Animal Drugs; Approval of New Animal Drug Applications. Federal Register, 29 August 2016, 81 FR 59131 (NADA 141-457, ENTYCE; adds 21 CFR 520.292). Also 1 April 2021, 86 FR 17061 (NADA 141-536, ELURA), and 11 January 2018, 83 FR 1365.

FDA approved NADA 141-457 (ENTYCE, capromorelin oral solution, dogs, appetite stimulation) on 16 May 2016, per the Federal Register rule of 29 August 2016 (81 FR 59131), which also added 21 CFR 520.292. FDA approved NADA 141-536 (ELURA, capromorelin oral solution, management of weight loss in cats with chronic kidney disease) on 16 October 2020, per the Federal Register rule of 1 April 2021 (86 FR 17061). A Federal Register notice of 11 January 2018 (83 FR 1365) records that NADA 141-457 was submitted on 22 March 2016 and approved on 16 May 2016, and that approval of ENTYCE was the first permitted commercial marketing of the product. Both approvals are animal drug approvals.

Participants / model
Not a clinical population
Treatment
Animal drug applications
Follow-up
Approvals in 2016 and 2020
Study design
Official US government record
Funding
not stated in the source

Both approvals are for animals. No approval for use in people is recorded.

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Older adults: 395 randomized, stopped early, lean body mass +1.4 versus +0.3 kg at 6 months

Randomized controlled trial

White HK et al. J Clin Endocrinol Metab. 2009;94(4):1198-206. PMID 19174493.

A sustained dose-related rise in IGF-1 occurred in all active groups, and each dose produced a rise in peak nocturnal GH, greatest with the least frequent dosing. At 6 months, body weight rose 1.4 kg on capromorelin and fell 0.2 kg on placebo (P=0.006), lean body mass rose 1.4 versus 0.3 kg (P=0.001), and tandem walk improved by 0.9 seconds (P=0.02) in the pooled treatment versus placebo groups. By 12 months stair climb also improved (P=0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin and indices of insulin resistance.

Participants / model
395 men and women aged 65 to 84 with mild functional limitation
Treatment
Oral capromorelin in four regimens (10 mg three times a week, 3 mg twice a day, 10 mg each night, 10 mg twice a day) or placebo
Follow-up
Intended 2 years; terminated early; 315 completed 6 months and 284 completed 12 months
Study design
Randomized, double-masked, placebo-controlled multicenter trial
Funding
not stated in the source

Stopped early according to predetermined treatment effect criteria. The population is older adults with mild functional limitation, not healthy or trained people.

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Phase 1: spinal cord injured and able-bodied volunteers, single doses, no serious adverse events

Clinical trial

Ellis AG et al. Spinal Cord. 2015;53(2):103-8. PMID 25448190.

No serious adverse events were recorded in either group, there were no abnormal blood pressure or heart rate changes, and minor adverse events resolved quickly. Both groups showed dose-dependent increases in Cmax and AUC. The spinal cord injured participants showed greater variance in pharmacokinetic parameters and a slightly delayed Tmax and half-life. The published abstract gives no numeric pharmacokinetic values.

Participants / model
Spinal cord injured and able-bodied adult volunteers; number not stated in the source
Treatment
Oral capromorelin, 20, 50 and then 100 mg, at least 1 week apart
Follow-up
Single doses with 12 hours of PK sampling and 1-week and 4-week safety follow-up
Study design
Single-center single ascending dose phase 1 trial
Funding
not stated in the source

The abstract gives no numeric Cmax, AUC, Tmax or half-life, so none are carried onto this page.

Read the original source
Beagles: 6 dogs, 7 days, GH rise smaller on days 4 and 7, IGF-1 sustained

Animal study

Zollers B et al. J Vet Pharmacol Ther. 2017;40(2):140-147. PMID 27597271.

Capromorelin increased food consumption and body weight versus placebo and raised serum GH, which returned to baseline by 8 hours after dosing. The magnitude of the GH increase was less on days 4 and 7 than on day 1. IGF-1 rose on day 1 and the increase was sustained through day 7. Serum cortisol also rose after dosing and returned to baseline by 8 hours, again with a smaller increase on days 4 and 7. The authors propose that sustained IGF-1 may increase lean muscle mass over extended periods, which they did not measure.

Participants / model
6 healthy adult Beagle dogs
Treatment
Oral capromorelin: placebo twice daily, 3.0 mg/kg once daily, 4.5 mg/kg once daily or 3.0 mg/kg twice daily
Follow-up
7 days
Study design
Controlled animal study
Funding
not stated in the source

This is a dog study. The GH response shrank on repeat dosing while IGF-1 did not.

Read the original source
Preclinical: rat pituitary cells EC50 3 nM; pulsatile GH release in rats and dogs

Animal study

Pan LC et al. Endocrine. 2001;14(1):121-32. PMID 11322494.

CP-424,391 (capromorelin) stimulated GH release from rat pituitary cell cultures with an EC50 of 3 nM, activated intracellular calcium signaling without raising cAMP, and required expression of the recombinant human GHS receptor to signal in nonpituitary cell lines. Acute administration to anesthetized rats or conscious dogs induced pulsatile GH release in a dose-dependent manner. Plasma IGF-1 rose progressively over a 5-day course of daily oral dosing in dogs, and chronic oral administration augmented body weight gain in rats and dogs.

Participants / model
Rat pituitary cells, nonpituitary cell lines, anesthetized rats and conscious dogs
Treatment
Capromorelin by oral and acute administration; doses not stated in the source
Follow-up
Acute dosing; 5-day oral course in dogs
Study design
Preclinical pharmacology study
Funding
not stated in the source

The word pulsatile in the supplier claim traces to this rat and dog work, not to a human study.

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Why is Capromorelin in C tier?

C fits a plausible mechanism with thin human outcome data. Capromorelin raises GH and IGF-1 in animals and older adults, and two FDA veterinary approvals rest on randomized field studies. The human file is one 395-person trial stopped early and one single-dose phase 1 study, with no human drug application and no ClinicalTrials.gov record found on 9 October 2026.