Phase II clinical trial of Wilms tumor 1 peptide vaccination for patients with recurrent glioblastoma multiforme.
OBJECTIVE
The object of this study was to investigate the safety and clinical responses of immunotherapy targeting the WT1 (Wilms tumor 1) gene product in patients with recurrent glioblastoma multiforme (GBM).


METHODS
Twenty-one patients with WT1/HLA-A*2402-positive recurrent GBM were included in a Phase II clinical study of WT1 vaccine therapy. In all patients, the tumors were resistant to standard therapy. Patients received intra-dermal injections of an HLA-A*2402-restricted, modified 9-mer WT1 peptide every week for 12 weeks. Tumor size, which was obtained by measuring the contrast-enhanced area on magnetic resonance images, was determined every 4 weeks. The responses were analyzed according to Response Evaluation Criteria in Solid Tumors (RECIST) 12 weeks after the initial vaccination. Patients who achieved an effective response continued to be vaccinated until tumor progression occurred. Progression-free survival and overall survival after initial WT1 treatment were estimated.


RESULTS
The protocol was well tolerated; only local erythema occurred at the WT1 vaccine injection site. The clinical responses were as follows: partial response in 2 patients, stable disease in 10 patients, and progressive disease in 9 patients. No patient had a complete response. The overall response rate (cases with complete or partial response) was 9.5%, and the disease control rate (cases with complete or partial response as well as those in which disease was stable) was 57.1%. The median progression-free survival (PFS) period was 20.0 weeks, and the 6-month (26-week) PFS rate was 33.3%.


CONCLUSIONS
Although a small uncontrolled nonrandomized trial, this study showed that WT1 vaccine therapy for patients with WT1/HLA-A*2402-positive recurrent GBM was safe and produced a clinical response. Based on these results, further clinical studies of WT1 vaccine therapy in patients with malignant glioma are warranted.
Izumoto
Shuichi
S
Department of Neurosurgery, Nagoya University, Nagoya, Japan. sizumoto@nsurg.med.osaka-u.ac.jp
Tsuboi
Akihiro
A
Oka
Yoshihiro
Y
Suzuki
Tsuyoshi
T
Hashiba
Tetsuo
T
Kagawa
Naoki
N
Hashimoto
Naoya
N
Maruno
Motohiko
M
Elisseeva
Olga A
OA
Shirakata
Toshiaki
T
Kawakami
Manabu
M
Oji
Yusuke
Y
Nishida
Sumiyuki
S
Ohno
Satoshi
S
Kawase
Ichiro
I
Hatazawa
Jun
J
Nakatsuka
Shin-Ichi
S
Aozasa
Katsuyuki
K
Morita
Satoshi
S
Sakamoto
Junichi
J
Sugiyama
Haruo
H
Yoshimine
Toshiki
T
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy; D019496:Cancer Vaccines / Q000627:therapeutic use*; D018797:Cell Cycle Proteins; D005260:Female; D005909:Glioblastoma / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D006801:Humans; D007271:Injections, Intradermal; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000276:immunology*; D000072260:RNA Splicing Factors; D016896:Treatment Outcome; D014611:Vaccination
D019496:Cancer Vaccines; D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; D000072260:RNA Splicing Factors; C419554:WTAP protein, human