Comparison
Degarelix vs. Semax
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
214766-78-6
80714-61-0
Molecular weight
1632.3 g/mol
813.92 g/mol
Half-life
1320 h
0.3 h
Sequence
Ac-D-2Nal-D-4Cpa-D-3Pal-Ser-4Aph(Hor)-D-4Aph(Cbm)-Leu-Ilys-Pro-D-Ala-NH2Met-Glu-His-Phe-Pro-Gly-ProMechanism of action
Degarelix
Degarelix is a competitive GnRH receptor antagonist. It binds reversibly and immediately to the pituitary GnRH receptors and blocks their activation. This rapidly suppresses the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which in turn lowers testosterone production in the testes. Unlike GnRH agonists (e.g., leuprorelin), which first cause a transient stimulation with a testosterone surge (flare), this direct antagonism lacks the initial stimulation phase, so testosterone declines without a preceding rise. This mechanism underlies the literature-described use in hormone-dependent prostate cancer.
Semax
Semax is a tetracosactide fragment analog without hormonal activity at MC2R. Proposed mechanisms include elevation of BDNF and NGF in hippocampus and striatum (in animal models), modulation of dopamine metabolism, and neuroprotective effects via anti-apoptotic pathways. A clear primary receptor is not established.
Evidence base
Highest evidence
Human RCT
Human trial
Studies
4
4
of which in humans
4
2
Effects recorded
4
3
Open conflicts
1
1
Documented adverse events
2
1
Legal status
Full entries
Frequently asked questions
- What is the difference between Degarelix and Semax?
- Degarelix is classified as "Research other", while Semax is classified as "Research other". Degarelix: Degarelix (trade name Firmagon) is a synthetic decapeptide and a gonadotropin-releasing hormone (GnRH) receptor antagonist. Unlike GnRH agonists, it blocks the receptor directly and does not trigger an initial testosterone surge (flare). It is an approved prescription medicine for the treatment of advanced, hormone-dependent prostate cancer. This page neutrally summarizes the evidence base and legal status and is not a usage or dosing recommendation. Semax: Synthetic heptapeptide derived from the N-terminal fragment of adrenocorticotropic hormone (ACTH 4-10). Approved in Russia for ischaemic stroke, cognitive function and ADHD in children. Western phase-3 trials absent. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Degarelix or Semax?
- The highest available evidence level is "Human RCT" for Degarelix and "Human trial" for Semax. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of Degarelix and Semax in Germany and the United States?
- Germany: Degarelix — Prescription, Semax — Unapproved. United States: Degarelix — Prescription, Semax — Unapproved. These are factual summaries with source and review date on the individual pages.