Sermorelin vs Tesamorelin
Two GHRH analogs on the same pituitary receptor, with very different regulatory histories.
Research use only. A summary of published literature for educational reference — not medical advice and not a guide to human use.
The short version
Both stimulate the pituitary GHRH receptor. Sermorelin is the short 1–29 fragment, once approved for paediatric diagnosis and treatment and later withdrawn commercially. Tesamorelin is a stabilised full-length analog approved for HIV-associated abdominal fat.
At a glance
Structure
GHRH(1-29) amide
Full-length GHRH(1-44) with trans-3-hexenoyl group
Approval status
Previously FDA-approved (Geref); discontinued
FDA-approved (Egrifta) for HIV lipodystrophy
Half-life
Minutes
Under an hour
Key endpoint
GH and IGF-1 rise
Visceral fat reduction in phase 3 trials
Research vial sizes
5 / 10 mg
10 / 20 mg
01How they work
Both bind the GHRH receptor on pituitary somatotrophs, triggering pulsatile growth hormone release and a downstream IGF-1 rise. Tesamorelin's modification resists enzyme breakdown, extending its activity.
02What studies measured
Tesamorelin phase 3 trials in people with HIV reported visceral fat falling 15.2% with tesamorelin versus rising 5.0% with placebo over 26 weeks (412 patients); a second 26-week phase 3 trial reported −24 versus +2 cm² of visceral fat. Sermorelin studies mainly report GH and IGF-1 biomarker changes rather than clinical outcomes.
03Reported side effects
Trial-reported events for tesamorelin include injection-site reactions, joint pain, fluid retention and raised glucose; IGF-1 monitoring is described in labelling. Sermorelin reports are mostly injection-site reactions and flushing.
04Approval & evidence status
Tesamorelin remains approved for its narrow indication. Sermorelin's branded product was discontinued; it is now mainly compounded or sold for research.
Citations
- [1]Phase 3 randomized controlled trial2007
Metabolic effects of a growth hormone-releasing factor in patients with HIV
Falutz J, et al. N Engl J Med, 2007.
Read paper ↗ - [2]Pooled analysis of phase 3 RCTs2010
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
Falutz J, et al. J Clin Endocrinol Metab, 2010.
Read paper ↗ - [3]Editorial / expert commentary2006
Sermorelin: a better approach to management of adult-onset growth hormone insufficiency?
Walker RF. Clin Interv Aging, 2006.
Read paper ↗
Research use only. A summary of published literature for educational reference — not medical advice and not a guide to human use.