A vaccination strategy for the long-term suppression of androgens in advanced prostate cancer.
OBJECTIVE
We have previously reported the ability of D17DT (formerly GnRH-DT) vaccination to produce castrate levels of androgens in men with advanced prostate cancer. This study examines the efficacy and tolerability of 3 and 15 micrograms of D17DT in 12 patients with advanced prostate cancer to establish a dose-response relationship.


METHODS
12 patients received either 3 or 15 micrograms of D17DT as 3 deep intramuscular injections over 6 weeks. Outcome was assessed in terms of physical and biochemical evaluations of clinical progression and antibody titres.


RESULTS
Significant titres of anti-GnRH antibodies were detected in 2 out of 6 subjects who received 15 micrograms of D17DT; suppression of testosterone to castrate levels accompanied by a significant and prolonged reduction in PSA was also demonstrated. No responses were seen following treatment with 3 micrograms of D17DT.


CONCLUSIONS
The induction of anti-GnRH antibodies through vaccination with 15 micrograms D17DT can produce and sustain castrate levels of testosterone in men with advanced prostate cancer.
Parkinson
R J
RJ
Department of Urology, Nottingham City Hospital, Hucknall Road, NG5 1PB Nottingham, UK. lallyandrich@hotmail.com
Simms
M S
MS
Broome
P
P
Humphreys
J E
JE
Bishop
M C
MC
D000726:Androgen Antagonists / Q000627:therapeutic use; D019496:Cancer Vaccines / Q000008:administration & dosage* / Q000276:immunology; D004168:Diphtheria Toxoid / Q000737:chemistry / Q000276:immunology*; D018450:Disease Progression; D004305:Dose-Response Relationship, Drug; D007987:Gonadotropin-Releasing Hormone / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D008297:Male; D009842:Oligopeptides / Q000737:chemistry / Q000276:immunology*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000517:prevention & control*; D013739:Testosterone / Q000097:blood
D000726:Androgen Antagonists; D019496:Cancer Vaccines; D004168:Diphtheria Toxoid; D009842:Oligopeptides; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D017430:Prostate-Specific Antigen