title: Extended release, 6-month formulations of leuprolide acetate for the treatment of advanced prostate cancer: achieving testosterone levels below 20 ng/dl.
abstract: BACKGROUND
  Luteinizing hormone-releasing hormone agonists such as leuprolide acetate (LA) are the most frequently utilized treatment of advanced prostate cancer as the regimen for achieving androgen deprivation therapy (ADT). The efficacy of LA is determined by extent of testosterone (T) suppression in prostate cancer patients. Although, the historical castrate T suppression target has been defined as < 50 ng/dl, this level may not be as low as required to deliver equivalent suppression as achieved by surgical castration. Recent studies have demonstrated that a T level as low as 20 ng/dl may produce improved clinical outcomes.
  
  
  METHODS
  LA is available in long-acting formulations that deliver active drug over the course of 1-6 months from a single-dose administration. The technologies utilized to provide sustained drug delivery differ: one mode of administration uses microspheres, which encapsulate the drug and are injected as a suspension intramuscularly; another mode of administration uses a liquid polymer that creates a single, solid depot after injection subcutaneously. This article will review the safety and efficacy of both 6-month LA formulations, as well as their impact in prostate cancer treatment.
  
  
  CONCLUSIONS
  As the understanding of optimal T castrate level evolves and may be refined pending new data from contemporaneous trials, achievement and maintenance of T levels well below 50 ng/dl may be important in evaluating potential differences in ADT regimens.
authors: a 1 University of Colorado Cancer Center, University of Colorado Health Sciences Center, Urologic Oncology Department , Mail Stop F710, 1665 N. Ursula Street, Rm 1004, P.O. Box 6510, Aurora, CO 80045, USA +1 720 848 0195 ; +1 720 848 0203 ; edc@edavidcrawford.com.
authors: E David
authors: ED
authors: Crawford
authors: Judd W
authors: JW
authors: Moul
authors: Oliver
authors: O
authors: Sartor
authors: Neal D
authors: ND
authors: Shore
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D015195:Drug Design; D006801:Humans; D016729:Leuprolide / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D013739:Testosterone / Q000097:blood
chemical_list: D018931:Antineoplastic Agents, Hormonal; D003692:Delayed-Action Preparations; D013739:Testosterone; D016729:Leuprolide
keywords: biodegradable polymer; depot; leuprolide acetate; leuprorelin; microspheres; prostate cancer