Abstract 3964
Background
Immune checkpoint inhibitors (CPI) have revolutionised the treatment of solid tumours with durable responses in cancers with previously limited treatment options. Despite significant improvements in overall survival for some patients(pt), identifying biomarkers to select a population most likely to benefit from CPIs remains challenging.
Methods
We characterized fresh tumour biopsies from 82 pts with metastatic cancer through the Personalised OncoGenomics (POG) program at BC Cancer using whole genome (80X tumour, 40X normal) and transcriptome analysis (WGTA). Subsequently pts were treated with a CPI as part of their standard cancer care. Baseline characteristics and follow up data were collected retrospectively. Durable clinical benefit (DCB) was defined as > 6 months(m) without disease progression and overall survival (OS) from date of first CPI treatment to death.
Results
The 82 pts (59% female) biopsied comprised a heterogeneous cohort: non-small cell lung cancer (30%), breast (17%) and colorectal cancer (13%) were most common, and most patients (45%) had received 1-2 prior treatments. 17 patients (21%) had a DCB and the median follow-up from first dose CPI was 9.2m. Higher tumour mutation burden (>10mut/Mb exome) was predictive of a longer median time to progression/death (TTPD) (5.9 vs 2.6m, p = 0.0055, HR = 0.44) and OS (14.6 vs 7.9m, p = 0.039, HR = 0.52). A higher predicted CD8+ T cell score (CIBERSORT) also predicted for a prolonged median TTPD (3.4 vs 2.4 m, p = 0.0094, HR = 0.51) and OS (12.9 vs 5.3m, p = 0.0014, HR = 0.42). In contrast, patients with PD-L1 expression > 80th percentile did not have a significantly different TTPD or OS. In addition to characterizing individual biomarkers, we note that patients with combinations of markers, particularly high TMB and CD8+ T cell scores, have a further improvement in median TTPD (5.9 vs 2.4m, p = 0.013) and OS (14.5 vs 5.4m, p = 0.014).
Conclusions
The complexity of interpreting the tumour-immune interface to predict CPI efficacy remains challenging, but WGTA allows for identification of combination biomarkers that may help to identify responders. The presence of two or more biomarkers predicted for CPI response in this patient cohort and may more successfully identify these patients in prospective studies.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
BC Cancer Foundation.
Disclosure
J. Lavoie: Research grant / Funding (self): University of British Columbia. S. Yip: Advisory / Consultancy: Pfizer; Advisory / Consultancy: Roche; Advisory / Consultancy: Bayer. D. Renouf: Honoraria (self): Celgene; Honoraria (self): Servier; Honoraria (self): Taiho; Honoraria (self): Ipsen; Honoraria (self), Research grant / Funding (institution): Bayer. J.J. Laskin: Honoraria (self), Research grant / Funding (institution): Roche Canada; Honoraria (self): BI Canada; Honoraria (self), Research grant / Funding (institution): AstraZeneca Canada; Research grant / Funding (institution): Pfizer Canada. All other authors have declared no conflicts of interest.
Resources from the same session
3252 - Genes involved in DNA replication, chromatin remodeling and cell cycle as potential biomarkers for therapy outcome to immune therapy in patients with metastatic cutaneous malignant melanoma
Presenter: Fernanda Costa Svedman
Session: Poster Display session 3
Resources:
Abstract
5545 - Phase Ib/II Study (SENSITIZE) assessing safety, pharmacokinetics (PK), pharmacodynamics (PD), and clinical outcome of domatinostat in combination with pembrolizumab in patients with advanced melanoma refractory/non-responding to prior checkpoint inhibitor therapy
Presenter: Jessica Hassel
Session: Poster Display session 3
Resources:
Abstract
5213 - Genomic landscape of primary malignant melanoma of esophagus
Presenter: Jie Dai
Session: Poster Display session 3
Resources:
Abstract
2716 - A phase III, randomised, double-blind study of adjuvant cemiplimab versus placebo post-surgery and radiation in patients with high-risk cutaneous squamous cell carcinoma (CSCC)
Presenter: Danny Rischin
Session: Poster Display session 3
Resources:
Abstract
3550 - ILLUMINATE 301: A randomized phase 3 study of tilsotolimod in combination with ipilimumab compared with ipilimumab alone in patients with advanced melanoma following progression on or after anti-PD-1 therapy
Presenter: Marcus Butler
Session: Poster Display session 3
Resources:
Abstract
1645 - PRIME002 - Early phase II study of Azacitidine and Carboplatin priming for Avelumab in patients with advanced melanoma who are resistant to immunotherapy
Presenter: Andre Van Der Westhuizen
Session: Poster Display session 3
Resources:
Abstract
4440 - Pembrolizumab (pembro) Plus Lenvatinib (len) for First-Line Treatment of patients (pts) With Advanced Melanoma: Phase 3 LEAP-003 Study
Presenter: Alexander Eggermont
Session: Poster Display session 3
Resources:
Abstract
3454 - Proof of concept study with the histone deacetylase inhibitor vorinostat in patients with resistant BRAFV600 mutated advanced melanoma
Presenter: Sanne Huijberts
Session: Poster Display session 3
Resources:
Abstract
1832 - A phase Ia/Ib clinical study to evaluate the safety, pharmacokinetics (PK) and preliminary anti-tumor activity of FCN-159 in patients with advanced melanoma harboring NRAS-aberrant (Ia) and NRAS-mutation (Ib).
Presenter: Lu Si
Session: Poster Display session 3
Resources:
Abstract
3996 - A Phase I Clinical Trial Investigating the Therapeutic Cancer Vaccine UV1 in Combination with Pembrolizumab as First-Line Treatment of Patients with Malignant Melanoma
Presenter: Sanjiv Agarwala
Session: Poster Display session 3
Resources:
Abstract