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
2743 - The Impact of Targeted Therapies and Immunotherapy in Melanoma Brain Metastases: a Systematic Review and Meta-Analysis
Presenter: Mario Mandala
Session: Poster Display session 3
Resources:
Abstract
5479 - Intracranial Anti-Tumor Activity in Melanoma Brain Metastases with Encorafenib Plus Binimetinib: A Multicenter, Retrospective Analysis
Presenter: Jose Lutzky
Session: Poster Display session 3
Resources:
Abstract
3560 - Outcomes of Patients with Melanoma Brain Metastases (MBM) Treated with Standard of Care Therapy After Being Excluded from MBM-Specific Clinical Trials
Presenter: Kourtney Holbrook
Session: Poster Display session 3
Resources:
Abstract
3175 - The analysis of current treatment outcomes in melanoma patients with brain metastases
Presenter: Joanna Placzke
Session: Poster Display session 3
Resources:
Abstract
4550 - A multivariate model to define prognostic groups among patients with melanoma brain metastases: a 10-year retrospective cohort study
Presenter: Giacomo Pelizzari
Session: Poster Display session 3
Resources:
Abstract
4191 - The immune landscape of melanoma significantly influences survival in patients with highly mutated tumors.
Presenter: Robert Ferguson
Session: Poster Display session 3
Resources:
Abstract
1625 - Final Results from Phase II of Combination with Canerpaturev (formerly HF10), an Oncolytic Viral Immunotherapy, and Ipilimumab in Unresectable or Metastatic Melanoma in 2nd-or later line treatment
Presenter: Kenji Yokota
Session: Poster Display session 3
Resources:
Abstract
5346 - Evaluating polygenic risk score prediction model for melanoma prognosis
Presenter: Miriam Potrony
Session: Poster Display session 3
Resources:
Abstract
5477 - Impact of sarcopenia in patients with metastatic melanoma treated with immunotherapy
Presenter: Maria Grazia Vitale
Session: Poster Display session 3
Resources:
Abstract
3469 - Ancillary evaluation of systemic immune antitumor response (SIAR) and tumor growth rate (TGR) of patients (pts) with metastatic melanoma (MM) treated with radiotherapy (RT) combined with ipilimumab (ipi) in the phase 1 study Mel-Ipi-Rx.
Presenter: Celine Boutros
Session: Poster Display session 3
Resources:
Abstract