Abstract 2219
Background
Racotumomab is an anti-idiotype vaccine, a mirror image of N-Glycolylneuraminic acid (NeuGcGM3), which mimics this ganglioside and triggers an immune response in various tumors. In this study we investigated the prognostic significance of tissue NeuGcGM3 expression level and prognostic as well as predictive value of circulating tumor cell count monitoring in patients on Racotumomab treatment.
Methods
Out of 48 patients characterized, 40 were non-small cell lung cancer (NSCLC), 12 stage III and 28 stage IV. 19 Adenocarcinoma and 21 Squamous Ca. 2 were small cell lung cancer (SCLC) and 6 with other carcinomas. Male/Female ratio was 3.36(37/11) and median age was 63 (31-84). All patients received Racotumomab as switch maintenance after chemotherapy. 7 PD-L1 (+) Pts also received check point inhibitors on progression. Expression of NeuGcGM3 was detected with 14F7 monoclonal antibody IHC staining and graded as 0,1+,2+ or 3+ according to intensity. Circulating tumor cell (CTC) count was monitored using Cell Sorter throughout the treatment course, before starting Racotumomab and every 3 months or on clinical progression.
Results
NeuGcGM3 IHC were performed 25 out of 48 patients whose paraffin blocks were available. 9 Patients had strong (3+), 12 had (2+) and 4 patients had (1+) NeuGcGM3 staining intensity. There was no statistically significant difference in the mean overall survival of the patients according to IHC staining level (1+) mean OS:55.3 months, (2+) mean OS:40.9 months, and (3+) OS:39.0 months. In 14 Patients, circulating tumor cell count was monitored from the blood and correlated well with clinical outcomes in 11 out of 14 patients (%78.5). Significant reduction of the CTC counts was compatible with clinical response whereas increased CTC counts were early messengers for clinical progression.
Conclusions
This study revealed that any grade of NeuGcGM3 positivity in the tumor tissue is adequate to select a patient for Racotumomab treatment regardless of the IHC intensity. We also concluded that CTC monitoring in patients receiving immunotherapy is a good predictive and prognostic tool.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Necdet Uskent.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2507 - KEYLYNK-010: Phase 3 Study of Pembrolizumab (pembro) Plus Olaparib (OLA) vs Enzalutamide (ENZA) or Abiraterone (ABI) in ENZA- or ABI-Pretreated Patients (pts) With Metastatic Castration-Resistant Prostate Cancer (mCRPC) Who Had Progression on Chemotherapy (CTx)
Presenter: Evan Yu
Session: Poster Display session 3
Resources:
Abstract
2944 - PROSTRATEGY: A Spanish Genitourinary Oncology Group (SOGUG) multi-arm multistage (MAMS) phase III trial of immunotherapy strategies in high-volume metastasic hormone-sensitive prostate cancer.
Presenter: Jose Arranz Arija
Session: Poster Display session 3
Resources:
Abstract
3535 - A phase 1 study of AMG 160, a half-life extended bispecific T cell engager (HLE BiTE) immuno-oncology therapy targeting PSMA, in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC)
Presenter: Ben Tran
Session: Poster Display session 3
Resources:
Abstract
4951 - ProBio: An outcome-adaptive, multi-arm, open-label, multiple assignment randomised controlled biomarker-driven trial in patients with metastatic castration-resistant prostate cancer (EudraCT: 2018-002350-78, NCT03903835)
Presenter: Johan Lindberg
Session: Poster Display session 3
Resources:
Abstract
2892 - A phase 3 randomized, placebo-controlled, double-blind study of niraparib plus abiraterone acetate and prednisone versus abiraterone acetate and prednisone in patients with metastatic prostate cancer (NCT03748641)
Presenter: Kim Chi
Session: Poster Display session 3
Resources:
Abstract
2427 - The Extended/Phase II Study of Safety And Tolerability Of Proxalutamide (GT0918) In Subjects With Metastatic Castrate Resistant Prostate Cancer (mCRPC) Who Failed Either Abiraterone (Abi) Or Enzalutamide (Enza)
Presenter: Nicholas Vogelzang
Session: Poster Display session 3
Resources:
Abstract
3224 - Addition of an oral docetaxel treatment (ModraDoc006/r) to androgen deprivation therapy (ADT) and intensity-modulated radiation therapy (IMRT) in patients with high risk N+M0 prostate cancer
Presenter: Marit Vermunt
Session: Poster Display session 3
Resources:
Abstract
3312 - A phase II randomized, open-label study comparing salvage radiotherapy in combination with 6 months of androgen-deprivation therapy with LHRH agonist or antagonist versus anti-androgen therapy with apalutamide in patients with biochemical progression after radical prostatectomy.
Presenter: Piet Dirix
Session: Poster Display session 3
Resources:
Abstract
2829 - Health-Related Quality of Life (HRQoL) and Updated Follow-Up From KEYNOTE-057: Phase 2 Study of Pembrolizumab (pembro) for Patients (pts) With High-Risk (HR) Non–Muscle Invasive Bladder Cancer (NMIBC) Unresponsive to Bacillus Calmette-Guérin (BCG)
Presenter: Ronald de Wit
Session: Poster Display session 3
Resources:
Abstract
2673 - Clinical activity of vofatamab (V), an FGFR3 selective antibody in combination with pembrolizumab (P) in metastatic urothelial carcinoma (mUC), updated interim analysis of FIERCE-22
Presenter: Arlene Siefker-Radtke
Session: Poster Display session 3
Resources:
Abstract