Emerging gonadotropin-releasing hormone agonists.

INTRODUCTION: Gonadotropin-releasing hormone agonist analogs (GnRHa) are peptides that mimic the action of gonadotropin-releasing hormone (GnRH) and are used to suppress subsequent sex steroid production. Although the analogs are a rather defined group of drugs, there have been developments in the past decades and there is still ample room for improvement. New therapeutic strategies in the use of GnRHs are discussed. AREAS COVERED: Major points of discussion include: i) the use of concomitant treatment of early breast cancer in premenopausal estrogen-positive and -negative patients, ii) the use of GnRHa for fertility preservation in young female patients with malignant diseases and iii) the use of GnRH analogs in assisted reproduction. The manuscript provides a better understanding of GnRH agonists as well as an explanation of their major indications, biochemical pathways and concluding therapeutic strategies. Recent results from international meetings and debates are described to explain current controversies. EXPERT OPINION: This paper highlights the need for more complex GnRH analogs. In the next few years, there will be longer acting GnRHas that may improve adherence. New therapeutic targets in oncological concepts may go beyond fertility preservation and focus on the antiproliferative effects of GnRH analogs.