Peptide Database
265 therapeutic peptides with research summaries, clinical findings, and regulatory status.
Leuprolide (Lupron)
A synthetic nonapeptide GnRH agonist approximately 15-fold more potent than native GnRH. After an initial stimulatory phase (flare effect) lasting 1-2 weeks, chronic leuprolide administration downregulates pituitary GnRH receptors, resulting in profound suppression of LH, FSH, and downstream sex steroids. This chemical castration effect is exploited in treating hormone-sensitive cancers, endometriosis, and precocious puberty.
Goserelin (Zoladex)
A synthetic decapeptide GnRH agonist administered as a biodegradable subcutaneous implant that provides sustained drug release over 1 or 3 months. Like other GnRH agonists, goserelin initially stimulates and then suppresses the HPG axis, reducing sex hormone production to castrate or postmenopausal levels. The implant formulation eliminates the need for repeated injections and ensures compliance.
Cetrorelix (Cetrotide)
A synthetic decapeptide GnRH antagonist that competitively blocks pituitary GnRH receptors, producing immediate and dose-dependent suppression of LH and FSH without the initial flare effect seen with GnRH agonists. Cetrorelix prevents premature LH surges during controlled ovarian stimulation in IVF, allowing precise timing of oocyte maturation and retrieval.
Ganirelix
A synthetic decapeptide GnRH antagonist that competitively and reversibly blocks GnRH receptors on pituitary gonadotroph cells. Ganirelix rapidly suppresses LH secretion within hours of administration, preventing premature ovulation during assisted reproductive technology (ART) cycles. Its mechanism provides immediate suppression without the flare phase associated with GnRH agonists.
Carbetocin
A long-acting synthetic analog of oxytocin with a modified disulfide bridge that confers resistance to enzymatic degradation. Carbetocin has a half-life of approximately 40 minutes compared to 3-5 minutes for oxytocin, providing sustained uterotonic activity after a single injection. It selectively binds oxytocin receptors in the myometrium, promoting uterine contraction and reducing postpartum blood loss.
Atosiban
A competitive oxytocin/vasopressin V1a receptor antagonist used as a tocolytic agent to delay preterm labor. Atosiban blocks oxytocin-mediated myometrial contractions without the cardiovascular side effects associated with beta-adrenergic tocolytics. The peptide is administered as an initial bolus followed by a step-down infusion protocol over up to 48 hours.
Nafarelin (Synarel)
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.
Choriogonadotropin Alfa (Ovidrel)
Choriogonadotropin alfa is a recombinant human chorionic gonadotropin produced in Chinese hamster ovary cells with identical amino acid sequence to endogenous hCG. The 237-amino acid heterodimeric glycoprotein binds the LH/hCG receptor on ovarian granulosa and theca cells to trigger final oocyte maturation and ovulation. It is used in assisted reproductive technology protocols to time oocyte retrieval and support luteal phase progesterone production.
Follitropin Alfa (Gonal-F)
Follitropin alfa is a recombinant human follicle-stimulating hormone produced in Chinese hamster ovary cells, consisting of a heterodimeric glycoprotein with 92-amino acid alpha and 111-amino acid beta subunits. The peptide binds FSH receptors on ovarian granulosa cells to stimulate follicular development, estradiol synthesis, and oocyte maturation. It is employed in ovulation induction and controlled ovarian stimulation for assisted reproductive technologies.
Menotropin (Menopur)
Menotropin is a purified preparation of human menopausal gonadotropins extracted from the urine of postmenopausal women, containing both follicle-stimulating hormone and luteinizing hormone activity in approximately equal proportions. The combination of FSH and LH bioactivity stimulates follicular recruitment, granulosa cell proliferation, and steroidogenesis in ovarian theca cells. It is indicated for ovulation induction in anovulatory infertility and controlled ovarian hyperstimulation in assisted reproduction.
Corifollitropin Alfa (Elonva)
Corifollitropin alfa is a recombinant long-acting FSH analogue created by fusing the C-terminal peptide of the hCG beta subunit to the FSH beta chain. This structural modification extends the elimination half-life to approximately 70 hours, enabling a single injection to sustain follicular stimulation for seven days. The agent is designed to simplify controlled ovarian stimulation protocols by replacing the first week of daily FSH injections in IVF cycles.
Cetrorelix (Cetrotide) Analog
Cetrorelix is a synthetic decapeptide analog of gonadotropin-releasing hormone (GnRH) that acts as a competitive GnRH receptor antagonist. By binding to pituitary GnRH receptors, it rapidly suppresses luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion without the initial agonist flare seen with GnRH agonists. This property makes it valuable for controlled ovarian stimulation protocols, where prevention of premature LH surges is critical for optimizing oocyte retrieval timing.