How good do current LHRH agonists LHRH agonists control testosterone? - Can this be improved with Eligard (R) ?

Following the discovery that prostate tumour growth is androgen-dependent, androgen suppression as achieved with orchiectomy (standard of castration) has been shown to delay tumour progression, improve symptoms and disease specific survival. Since the seventies hormone therapy with luteinising hormone releasing hormone (LHRH) agonists has constituted the main approach for suppressing testosterone in the treatment of advanced and metastatic prostate cancer. The availability of sustained-release formulations of LHRH agonists has greatly increased the patients' treatment compliance and contributed to the current widespread use of these agents. So far, it was assumed that LHRH agonists are equivalent to surgical castration in terms of achieving similar low levels of testosterone and maintaining these low levels over time. With the advent of new generation testosterone assays, several authors have reported that a considerable proportion of the patients receiving conventional LHRH agonists do not reach the testosterone levels as achieved with surgical castration (bilateral orchiectomy). In addition, testosterone rises, manifesting as breakthrough or acute-on-chronic testosterone responses, are relatively common. Hence, in order to optimise the proportion of patients achieving testosterone levels similar to surgical castration, and to reduce the occurrence of breakthrough and acute-on-chronic responses, a new sustained-release formulation of leuprolide, Eligard (R), has been developed. Eligard (R) has been shown to suppress testosterone to a level similar to orchiectomy in almost all patients, with a very low prevalence of breakthrough and acute-on-chronic responses. This is achieved through providing a higher dose of leuprolide compared to other formulations and by delivering an improved sustained release over the delivery period. Side effects seen with Eligard (R) are similar to those seen with the older LHRH agonist formulations. It this sense Eligard (R) provides an op