Triptorelin in androgen depravation therapy of advanced prostate cancer

Abstract

Triptorelin as the luteinizing hormone releasing hormone (LHRH) analogue has its own place among other available forms of androgen-depravation therapy (ADT) of locally advanced and metastatic prostate cancer (PCa). Nowadays, in times of development of new therapies in castration-resistant PCa, ADT remains the back bone therapy, which may be supplemented with one of novel drugs. The results of basic research indicate, that apart from the main mechanism of action based on lowering a testosterone concentration to the castration level, triptorelin may have a direct inhibitory effect on tumor cells. Formulations of tryptorelin are available to administer as 1-month, 3-months and 6-months sustained-release forms that may be given intramuscularly or subcutaneously. Constant concentration of triptoreline is maintained by using special microspheres in drug production. Pharmacokinetic and pharmacodynamic properties of particular forms were extensively tested, which allows for safe usage and retain of predictable and high efficacy.Indicators of effective ADT are fast reduction and maintenance of the state of castration. This phenomenon translates into a decrease of the prostate-specific antigen and longer survival. Triptorelin successfully meets these objectives based on a number of phase I–III studies. There is a noticeable lack of comparative studies on effectiveness of particular ADT forms. This may stem from an assumption, that all LHRH analogues demonstrate similar effectiveness because of the class effect. However, some evidence highlight significant differences in efficacy among these drugs. Triptorelin compares especially favourably, particularly as a drug reducing the testosterone level to the lower recommended values (< 20 ng/dl).Side effect profile during the therapy with triptorelin is largely the result of inhibition of the hypothalamic-pituitary-testicular axis. Hormonal disturbances linked to hipoandrogenism cause changes in lipid metabolism and glucose tolerance, which may influence the cardiovascular risk. This article is a review of key reports regarding triptorelin and a summary of the role that triptorelin plays in contemporary ADT in advanced PCa.