Results of a phase 3 trial showed that maintenance therapy with the anti-programmed cell death ligand 1 (PD-L1) antibody, avelumab, was not superior to continuation of first-line chemotherapy with respect to overall survival (OS) in patients with HER2-negative, advanced gastric or gastroesophageal junction cancer. The findings from this study were presented at the 2020 Gastrointestinal Cancers Symposium held in San Francisco, California.
For patients with incurable gastric and esophageal cancers, as well as other gastrointestinal cancers, there is controversy regarding whether upfront chemotherapy should be continued until disease progression or discontinued after achievement of disease control. In the latter scenario, administration of a less-intensive maintenance regimen would be an option to potentially extend the favorable results achieved with upfront chemotherapy.
Patients with HER2-negative advanced gastric or gastroesophageal junction cancer enrolled in this open-label, phase 3 clinical trial (JAVELIN Gastric 100; ClinicalTrials.gov Identifier: NCT02625610) had completed 12 weeks of first-line chemotherapy with oxaliplatin plus either 5-fluorouracil or capecitabine and achieved at least stable disease.
The primary endpoint of the study was OS following induction chemotherapy in all randomized patients or in all patients classified as having PD-L1–positive disease (ie, at least 1% of tumor cells classified as PD-L1–positive). Secondary study endpoints included progression-free survival (PFS), and best overall response in maintenance phase.
Of the 499 patients who underwent randomization following induction chemotherapy, 249 and 250 continued the induction chemotherapy regimen or received switch maintenance therapy with avelumab, respectively.
At a minimum follow-up of 18 months, median OS was 10.4 months for patients receiving avelumab maintenance and 10.9 months for those who continued chemotherapy (hazard ratio [HR], 0.91; 95% CI, 0.74-1.11; P =.1779). In addition, no OS benefit was observed for avelumab compared with chemotherapy for the 54 patients with PD-L1–positive disease (HR, 1.13; 95% CI, 0.57-2.23). Similarly, no significant differences with respect to PFS or overall response rate were observed between the 2 study arms.
Regarding safety, fewer treatment-related grade 3 or higher adverse events were reported in the avelumab arm (12.8%) compared with the chemotherapy arm (32.8%).
Although avelumab showed clinical activity and was associated with fewer grade 3 or higher adverse events compared with a strategy involving continuation of oxaliplatin-fluoropyrimidine chemotherapy, the primary endpoint of the study was not met, as avelumab maintenance was not associated with superior OS compared with continuation of chemotherapy.
Disclosure: Some of the authors disclosed financial relationships with the pharmaceutical industry. For a full list of disclosures, please refer to the original study abstract.
Moehler MH, Dvorkin M. Ozguroglu M, et al. Results of the JAVELIN Gastric 100 phase 3 trial: Avelumab maintenance following first-line (1L) chemotherapy (CTx) vs continuation of CTx for HER2-advanced gastric or gastroesophagael junction cancer (GC/GEJC). J Clin Oncol. 2020;38(suppl 4):Abstract 278.
This article originally appeared on Cancer Therapy Advisor