Dexamethasone did not suppress immune boosting by personalized peptide vaccination for advanced prostate cancer patients.
BACKGROUND
To evaluate the immunological responses of personalized peptide vaccination combined with low-dose glucocorticoids for advanced hormone refractory prostate cancer (HRPC) patients (pts).


METHODS
Eleven pts with advanced HRPC were treated with the vaccination and low-dose glucocorticoids; 6 pts with 10 mg/day of prednisolone (PDL) followed by 1 mg/day of dexamethasone at the time of progression, 1 pt with PDL, and 4 pts with dexamethasone. Peptide-specific cellular and humoral responses were employed to monitor pre- and post- (6th) vaccination samples.


RESULTS
The vaccination combined with glucocorticoids was well tolerated with no severe adverse effects. Increments of IgG responses were observed in 1 of 4 or 8 of 10 pts tested who received PDL or dexamethasone, respectively, increment of cytotoxic T lymphocyte activity was observed in 2 of 4 or 5 of 7 pts tested, respectively. Vaccination with PDL or dexamethasone resulted in a decline of PSA (at least 50%) in 1 of 7 or 6 of 10 pts with significantly longer median TTP in the dexamethasone group, respectively.


CONCLUSIONS
Vaccination combined with dexamethasone could be recommended for further clinical trials from both immunological and clinical points of view.
Naito
Masayasu
M
Department of Immunology, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
Itoh
Kyogo
K
Komatsu
Nobukazu
N
Yamashita
Yuichi
Y
Shirakusa
Takafumi
T
Yamada
Akira
A
Moriya
Fukuko
F
Ayatuka
Hitoshi
H
Mohamed
Elnisr Rashed
ER
Matsuoka
Kei
K
Noguchi
Masanori
M