LBA36 – Association of PD-L1 expression and gene expression profiling with clinical response to pembrolizumab in patients with advanced recurrent ovarian cancer: results from the phase 2 KEYNOTE-100 study
Jonathan A. Ledermann (London, GB)
Results from the KEYNOTE-100 trial (NCT02674061) suggest that pembrolizumab (pembro) has clinical activity in patients (pts) with advanced ovarian cancer (AOC), and also suggests that PD-L1 expression (combined positive score [CPS] ≥10) was associated with response. This abstract explored other biomarkers that could be associated with response. In addition to PD-L1 CPS, T-cell-GEP (T-cell-inflamed 18-gene expression profile) was associated with a response to pembro monotherapy for treatment of AOC in a single-arm setting, while HRD (homologous recombination deficiency) biomarkers (like HRD genomic scar and BRCA 1/2 mutations) were not found to be associated with response.
937PD – A phase 2 trial of combination nivolumab and bevacizumab in recurrent ovarian cancer
Joyce F. Liu (Boston, US)
Single agent trials of immune checkpoint inhibitors that target PD1 or PDL1 have shown modest effect in ovarian Cancer. VEGF (vascular endothelial growth factor) has demonstrated immune-suppressive functions through mechanisms such as impairment of dendritic cell function and maturation. As a result, anti-VEGF therapy may enhance immunotherapeutic responses when combined with immune checkpoint inhibitors. This abstract presents results from a trial to investigate the combination of the anti-VEGF agent bevacizumab and the PD1 inhibitor nivolumab in women with recurrent ovarian cancer. Combination nivolumab + bevacizumab demonstrated clinical activity in women with recurrent ovarian cancer, with an overall confirmed response rate of 21% and a median PFS of 9.4 months. Further studies of anti-angiogenic and immune checkpoint blockade combinations in ovarian cancer are warranted.
LBA35 – TROPHIMMUN, a 2 cohort phase II trial of the anti-PD-L1 monoclonal antibody avelumab in chemo-resistant gestational trophoblastic neoplasia (GTN) patients: preliminary outcomes in cohort A
Benoit M. You (Lyon, FR)
PD-L1 is constitutively expressed in all GTN subtypes (Bolze et al. Int J Gynecol Cancer 2017). The objective of the TROPHIMMUN trial is to assess the efficacy of the anti-PD-L1 monoclonal antibody avelumab in patients with chemoresistant GTN. Preliminary TROPHIMMUN trial outcomes suggest that avelumab might be effective, and better tolerated than standard chemotherapy in patients with resistance to single chemotherapy. This is the first clinical trial reporting potential cures with a non-chemotherapy agent in patients with this rare cancer.