ReproductiveFDA Approved

Nafarelin (Synarel)

Overview

Nafarelin is a synthetic decapeptide analogue of gonadotropin-releasing hormone (GnRH) with substitutions at positions 6 and 10 that enhance receptor affinity and metabolic stability. Chronic administration leads to downregulation of pituitary GnRH receptors and suppression of gonadotropin secretion, resulting in a hypoestrogenic state. This mechanism is therapeutically exploited in conditions requiring ovarian suppression, including endometriosis and central precocious puberty.

Key Research Findings

FDA approval was granted in 1990 for the treatment of endometriosis based on randomized controlled trials demonstrating reduction in endometrial implants and pain symptoms. Subsequent approval for central precocious puberty followed from studies showing suppression of pubertal progression and improved adult height predictions. The agent has largely been supplanted by longer-acting GnRH analogues in clinical practice.

Route of Administration

Intranasal

Regulatory Status

FDA Approved

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