degarelix + letrozole

Degarelix + letrozole is a combination therapy used primarily in premenopausal women with hormone-sensitive breast cancer. This combination therapy consists of degarelix, a gonadotropin-releasing hormone (GnRH) antagonist, and letrozole, an aromatase inhibitor. ## Description Degarelix + letrozole is a combination therapy used in the neoadjuvant treatment of hormone-sensitive breast cancer in premenopausal women. Degarelix is a GnRH receptor antagonist that rapidly suppresses ovarian function by blocking GnRH receptors in the pituitary gland, reducing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, which leads to estradiol suppression. Letrozole is an aromatase inhibitor that further reduces estrogen levels by inhibiting the conversion of androgens to estrogens. Clinical trials have shown that degarelix achieves ovarian function suppression (OFS) more quickly and maintains it more effectively than triptorelin (a GnRH agonist) when combined with letrozole. In the TREND trial, degarelix + letrozole achieved optimal OFS three times faster than triptorelin + letrozole (median 3 vs 14 days) and maintained optimal OFS more consistently throughout treatment[1][5]. ## Mechanisms of Action Degarelix works by competitively binding to GnRH receptors in the pituitary gland, causing immediate suppression of LH and FSH, which leads to rapid reduction in estradiol levels without the initial hormone flare seen with GnRH agonists[3][6]. Letrozole inhibits the aromatase enzyme, preventing the conversion of androgens to estrogens, further reducing estrogen levels in the body. ## Clinical Evidence The TREND trial demonstrated that in premenopausal women receiving letrozole for neoadjuvant endocrine therapy, ovarian function suppression was achieved more quickly and maintained more effectively with degarelix than with triptorelin. Time to optimal OFS was three times faster for patients assigned to degarelix and letrozole than to triptorelin and letrozole (median, 3 vs 14 days; hazard ratio, 3.05; 95% CI, 1.65 to 5.65; P < .001)[1][2][5]. Furthermore, optimal OFS was maintained for all patients assigned degarelix plus letrozole during subsequent cycles, whereas 15.4% of patients assigned triptorelin plus letrozole had suboptimal OFS after cycle 1[2][5]. ## Adverse Events Adverse events for both degarelix + letrozole and triptorelin + letrozole were as expected based on the known safety profiles of these medications. Common adverse events included hot flashes, arthralgia, insomnia, injection site reactions, hypertension, and nausea[2][5].