Infusion of dendritic cells pulsed with HLA-A2-specific prostate-specific membrane antigen peptides: a phase II prostate cancer vaccine trial involving patients with hormone-refractory metastatic disease.
BACKGROUND
A phase II trial was conducted to assess the efficacy of infusions of dendritic cells (DC) and two HLA-A2-specific PSMA peptides (PSM-P1 and -P2). This report describes thirty three subjects with hormone-refractory metastatic prostate cancer without prior vaccine therapy history who were evaluated and reported as a group.


METHODS
All subjects received six infusions of DC pulsed with PSM-P1 and -P2 at six week intervals. Clinical monitoring was conducted pre-, during, and post- phase II study. Data collected include: complete blood count, bone and total alkaline phosphatase, prostate markers, physical examination, performance status, bone scan, ProstaScint scan, chest x-ray, as well as assays to monitor cellular immune responses.


RESULTS
Six partial and two complete responders were identified in the phase II study based on NPCP criteria, plus 50% reduction of prostate-specific antigen (PSA), or resolution in previously measurable lesions on ProstaScint scan.


CONCLUSIONS
Over 30% of study participants in this group showed a positive response at the conclusion of the trial. This study suggested that DC-based cancer vaccines may provide an alternative therapy for prostate cancer patients whose disease no longer responds to hormone therapy.
Murphy
G P
GP
Pacific Northwest Cancer Foundation, Cancer Research Division, Northwest Hospital, Seattle, Washington 98125, USA.
Tjoa
B A
BA
Simmons
S J
SJ
Jarisch
J
J
Bowes
V A
VA
Ragde
H
H
Rogers
M
M
Elgamal
A
A
Kenny
G M
GM
Cobb
O E
OE
Ireton
R C
RC
Troychak
M J
MJ
Salgaller
M L
ML
Boynton
A L
AL
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000008:administration & dosage / Q000627:therapeutic use; D000954:Antigens, Surface; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D019496:Cancer Vaccines / Q000008:administration & dosage / Q000627:therapeutic use*; D002268:Carboxypeptidases / Q000008:administration & dosage / Q000627:therapeutic use*; D003713:Dendritic Cells; D043425:Glutamate Carboxypeptidase II; D015789:HLA-A2 Antigen / Q000008:administration & dosage / Q000627:therapeutic use*; D006728:Hormones / Q000627:therapeutic use; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D011877:Radionuclide Imaging; D016896:Treatment Outcome; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000627:therapeutic use*