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IndexedBuilt automatically from public databases on 2026-09-30. Not yet hand-reviewed by PLOBT.How this works →

Nafarelin

FDA approved · Rx

GnRH agonist analog

Also known as: Synarel, Nafareline, Nafarelina, Nafarelinum, Lhrh, 6(d-nal(2)), 6-D-(2-naphthyl)alanyl-GnRH

Evidence score
91/ 100
Strong evidence

Strong, human-grade evidence

  • Regulatory standing. FDA-approved prescription medicine
  • Human trials. Backed by controlled human studies
  • Registered human trials. 12 registered studies on ClinicalTrials.gov, most advanced Phase 4
  • 2 cited sources. Includes primary / regulatory sources

Computed with the same four public criteria as every profile. The human-evidence grade on an indexed profile is set automatically and may change when it is hand-reviewed. It is not a safety score, not a purity rating, and not medical advice, and not a claim that this compound treats, cures, or prevents any condition.

What it is

Nafarelin is a synthetic peptide analog of gonadotropin-releasing hormone (GnRH), given as a nasal spray under the brand name Synarel. With continued use it is thought to first stimulate and then suppress the pituitary's release of LH and FSH, lowering sex hormone production by the ovaries or testes.

What the evidence shows

Automatic summaryHuman trials

Nafarelin is FDA-approved for the management of endometriosis and for central precocious puberty. It has a substantial published record, with 278 papers and 12 registered human trials reaching Phase 4.

Key facts

Molecular formula
C66H83N17O13
Molecular weight
1322.5 g/mol
FDA approval
Confirmed on openFDA

Registered human trials

Live from ClinicalTrials.gov, refreshed daily.

12registered studies
Phase 4most advanced phase
4completed (sample)
3recruiting (sample)

Comparison of Pregnancy Rates in Modified Natural Frozen Embryo Transfer (FET) Cycle After Luteal Support with GnRH Agonist Versus Progesterone

Early Phase 1Not Yet RecruitingNCT06870266

Natural Versus HRT Cycles in Frozen Embryo Replacement Treatment

Phase 4CompletedNCT00843570

GnRH for Luteal Support - Mechanism of Action

RecruitingNCT07620067

Short Versus Long Protocol for IVF and IVF+ICSI

Phase 4CompletedNCT00756028

Published literature

Live from Europe PMC. This is how much has been published, not how much is proven in humans.

279papers referencing Nafarelin

Administration of nasal nafarelin as compared with oral danazol for endometriosis. A multicenter double-blind comparative clinical trial.

N Engl J Med1988

The effect of nafarelin acetate, a luteinizing-hormone-releasing hormone agonist, on benign prostatic hyperplasia.

N Engl J Med1987

Ovarian hyperandrogynism as a result of congenital adrenal virilizing disorders: evidence for perinatal masculinization of neuroendocrine function in women.

J Clin Endocrinol Metab1994

Toward oral delivery of biopharmaceuticals: an assessment of the gastrointestinal stability of 17 peptide drugs.

Mol Pharm2015

Sources

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