Ipamorelin vs Tesamorelin

At a glance

Ipamorelin

A pentapeptide growth-hormone secretagogue noted in the literature for its selectivity — minimal cross-activity at cortisol and prolactin pathways compared to earlier GHRPs.

Ipamorelin is a 6-residue peptide with the molecular formula C38H49N9O5 and a molecular weight of 711.85 g/mol, CAS registry number 170851-70-4. The vial is sealed and lot-numbered, holds lyophilised powder, and is kept at −20°C protected from light until it ships.

Ipamorelin is a five-residue growth-hormone secretagogue originally developed by Novo Nordisk. It was never brought to market as a medicine and is available only as a research compound.

The 2 papers cited below are 1 study in humans and 1 animal study.

Cited on the Ipamorelin page

1. Raun K et al. (1998). Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. PubMed 9849822 · SummaryIn rats and pigs, ipamorelin released growth hormone without the ACTH or cortisol release seen with GHRP-6.
2. Gobburu JV et al. (1999). Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. PubMed 10496658 · SummaryPharmacokinetic–pharmacodynamic model in human volunteers: dose-dependent growth hormone release with a short plasma half-life.

Tesamorelin

A 44-amino-acid GHRH analog stabilised against enzymatic degradation. The most clinically characterised growth hormone releasing hormone in research use.

Tesamorelin is a synthetic peptide with the molecular formula C221H366N72O67S and a molecular weight of 5135.86 g/mol, CAS registry number 218949-48-5. The vial is sealed and lot-numbered, holds lyophilised powder, and is kept at −20°C protected from light until it ships.

Tesamorelin is a growth-hormone-releasing-hormone analog. A pharmaceutical form is FDA-approved under the name Egrifta for one specific indication. The research vial sold here is not that product and is not manufactured to its standard.

The 3 papers cited below are 3 studies in humans.

Cited on the Tesamorelin page

1. Falutz J et al. (2007). Metabolic effects of a growth hormone-releasing factor in patients with HIV. N Engl J Med. PubMed 18057338 · SummaryHIV patients with abdominal fat accumulation, 26 weeks: visceral adipose tissue fell about 15% against a rise on placebo.
2. Falutz J et al. (2010). 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. PubMed 20554713 · SummaryPooled analysis of two phase 3 trials: the visceral fat reduction held through 52 weeks of continued treatment and reversed on withdrawal.
3. Stanley TL et al. (2019). Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial. Lancet HIV. PubMed 31611038 · SummaryTwelve-month trial in HIV-associated liver fat: hepatic fat fraction fell and fewer participants progressed in fibrosis.

Handling the two side by side

Ipamorelin

• Lyophilised powder is stable for years at −20°C in the dark and tolerates days at ambient temperature in transit.

Tesamorelin

• Lyophilised powder is stable for years at −20°C in the dark and tolerates days at ambient temperature in transit.

Where to go next

• Ipamorelin and Tesamorelin: full specifications, stability notes, references and the certificate for the lot in stock.
• Growth hormone secretagogue comparison: how the whole group compares.
• How to read a certificate of analysis and the certificates page.