Session X: Esophageal and Gastric Cancers

LBA-4: Initial data from the phase 3 KEYNOTE-811 study of trastuzumab and chemotherapy with or without pembrolizumab for HER2-positive metastatic gastric or gastroesophageal junction (G/GEJ) cancer

Yelena Y. Janjigian

The study authors conclude that the combination of pembrolizumab, trastuzumab, and chemotherapy provides a substantial, statistically significant improvement in ORR compared with placebo, trastuzumab, and chemotherapy as 1st-line therapy for HER2-positive, metastatic G/GEJ cancer. They further conclude that along with the durability of responses and the manageable safety profile, their initial data support pembrolizumab plus trastuzumab and chemotherapy as a possible new treatment option for HER2-positive, metastatic G/ GEJ cancer.

 

O-15: Randomized, Phase 3 study of second-line tislelizumab vs chemotherapy in advanced or metastatic esophageal squamous cell carcinoma (RATIONALE 302) in the overall population and Europe/North America subgroup

Jaffer Ajani

The study authors conclude that 2nd-line tislelizumab demonstrated statistically significant and clinically meaningful improvement with a tolerable safety profile in overall survival versus chemotherapy in patients with advanced or metastatic ESCC. Efficacy and safety results from the EU/NA subgroup were consistent with the overall population.

 

LBA-5: Phase Ib study of the anti-TIGIT antibody tiragolumab in combination with atezolizumab in patients with metastatic esophageal cancer

Zev A. Wainberg

The study authors report results with tiragolumab, a human monoclonal antibody that binds TIGIT- (T-cell Immunoreceptor with Ig and ITIM domains) a novel inhibitory immune checkpoint present on activated T cells and NK cells in multiple cancers - to prevent its interaction with its ligand PVR. According to the study authors, tiragolumab combined with atezolizumab was well-tolerated with an acceptable safety profile. It showed preliminary antitumor activity in heavily pre-treated patients with metastatic esophageal cancers not previously treated with cancer immunotherapy.

 

O-13: Gut microbiome to predict survival time in advanced gastric cancer treated with nivolumab: the DELIVER trial (JACCRO GC-08)

Yu Sunakawa

The study authors demonstrated with their translational study that several genomic pathways and genera in the gut microbiome were significantly associated with survival time in patients with advanced gastric cancer treated with nivolumab. In addition, they found that the nucleotide metabolism pathway may potentially become a biomarker to predict the prognosis of nivolumab treatment in advanced gastric cancer.

 

O-14: Exploratory biomarker analysis of trastuzumab deruxtecan in DESTINY-Gastric01, a
randomized, phase 2, multicenter, open-label study in patients with HER2-positive or -low advanced gastric or gastroesophageal junction adenocarcinoma

Kohei Shitara

The study authors demonstrated in their post-hoc exploratory analysis clinically meaningful efficacy of T-DXd in HER2+ AGC regardless of the timing of testing for HER2 status or level of plasma ERBB2 amplification in ctDNA. They conclude that plasma ERBB2 copy number or HER2ECD warrants further investigation as a means to enrich a population of T-DXd treatment responders in HER2+ or HER2-low AGC.

 

SO-31: ASPEN-01: A Phase 1 study of ALX148, a CD47 blocker, in combination with trastuzumab, ramucirumab and paclitaxel in patients with 2nd line HER2-positive advanced gastric or gastroesophageal junction (G/GEJ) cancer

Hyun Cheol Chung

The study authors conclude that ALX148 in combination with trastuzumab, ramucirumab, and paclitaxel appears to be well tolerated with no DLTs or MTD reached. The RP2D of ALX148 is 15 mg/kg QW in combination. They further conclude that observed durable responses and initial survival estimates in patients with second-line disease - that had progressed upon prior HER2-directed therapy - warrants further study of this combination in patients with advanced HER2- positive G/GEJ cancer.