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
4370 - Continental differences in pathologic response with neoadjuvant ipilimumab (IPI) plus nivolumab (NIVO) in patients with macroscopic stage III melanoma in the phase 2 OpACIN-neo trial.
Presenter: Irene Reijers
Session: Poster Display session 3
Resources:
Abstract
3230 - Comparable responses of melanoma at primary site and synchronous lymph node metastases upon neoadjuvant ipilimumab (IPI) and nivolumab (NIVO)
Presenter: Judith Versluis
Session: Poster Display session 3
Resources:
Abstract
3171 - Adjuvant Therapies for Stage III Melanoma: Benchmarks for Bringing Clinical Trials to Clinical Practice
Presenter: Tina HIEKEN
Session: Poster Display session 3
Resources:
Abstract
3493 - Mixture-cure modeling for resected stage III/IV melanoma in the phase 3 CheckMate 238 trial
Presenter: Jeffrey Weber
Session: Poster Display session 3
Resources:
Abstract
3036 - An open-label, non-randomized, phase IIIb study of trametinib in combination with dabrafenib for patients with unresectable advanced BRAFV600-mutant melanoma: a subgroup analysis of patients with brain metastasis
Presenter: Caroline Dutriaux
Session: Poster Display session 3
Resources:
Abstract
2233 - Adverse event (AE) kinetics in patients (pts) treated with dabrafenib + trametinib (D + T) in the metastatic and adjuvant setting
Presenter: Jean Jacques Grob
Session: Poster Display session 3
Resources:
Abstract
2435 - A Single Arm, Open Label, Phase II, Multicenter Study to Assess the Detection of the BRAF V600 Mutation on cfDNA from Plasma in Patients with Advanced Melanoma
Presenter: Piotr Rutkowski
Session: Poster Display session 3
Resources:
Abstract
1766 - Efficacy and Safety of Dabrafenib and Trametinib in Patients with Metastatic BRAFV600 Mutation-positive Melanoma in the Real-World Setting – Interim results of the non-interventional COMBI-r study
Presenter: Carola Berking
Session: Poster Display session 3
Resources:
Abstract
2131 - Trial update: A randomized Phase Ib/II study of the selective small molecule Axl inhibitor Bemcentinib (BGB324) in combination with either dabrafenib/trametinib (D/T) or pembrolizumab in patients with metastatic melanoma
Presenter: Oddbjørn Straume
Session: Poster Display session 3
Resources:
Abstract
4074 - Analysis of pyrexia in patients (pts) treated with dabrafenib (D) and/or trametinib (T) across clinical trials
Presenter: Caroline Robert
Session: Poster Display session 3
Resources:
Abstract