Abstract 2782
Background
Median overall survival on 2nd line therapy of PDAC with 5-FU/LV plus oxaliplatin or nal-irinotecan is ∼ 5-6 m. PDAC is refractory to immune therapies and mutational burden is relatively low and tumor infiltrating CD8+ T cells are rare. AM0010 stimulates survival, expansion and cytotoxicity of intratumoral CD8+ T cells and induced immune activation, durable stable disease and a 1yr survival of 22.5% in salvage PDAC pts. AM0010 has synergistic immune and anti-tumor activity with platinums and 5-FU in preclinical cancer models.
Methods
This phase 1b clinical study studied the safety and efficacy of AM0010 +FOLFOX as ≥ 2nd line treatment of PDAC. Pts who progressed on a median of 2 prior therapies (range 1-3) were treated with AM0010 (5ug/kg SQ, qd) + FOLFOX (n = 21). The safety population (n = 25) included four additional pts with prior FOLFOX. Tumor responses were assessed using irRC. Serum cytokines, activation of blood derived T cells and peripheral T cell clonality were analyzed. Pre-existing tumor infiltrating CD8 T cells were quantified by IHC.
Results
AM0010 + FOLFOX was generally well tolerated. G3/4 TrAEs included thrombocytopenia (52%), anemia (40%) and neutropenia (36%). Most cytopenias were transient and met retreatment criteria within 2-5 days. A modified AM0010 dose schedule of 5 days on, 2 days off avoided G3/4 cytopenias while retaining the immune stimulation. As of 05/1/2017, 2 pts have remained on treatment for > 72 weeks. 19 pts had tumor assessment following irRC (2 CR, 1 PR, 11 SD). The ORR and DCR were 15.8% and 74%. With a median follow-up of 14.2 m (range 6.8-18.9), 10 patients were alive (48%), mPFS and mOS were 3.5 and 10.2 m. Treatment induced a sustained cytokine increase in the serum and an expansion of novel T cell clones in the blood. This and a higher number of intra-tumoral CD8 T cells correlated with increased OS.
Conclusions
The combination of AM0010 with FOLFOX is well tolerated in patients with metastatic PDAC. This regimen induced sustained immune activation including the expansion of oligoclonal T cells. The prolonged tumor responses and OS are encouraging in this advanced population. This regimen is being studied in a phase 3 trial.
Clinical trial identification
NCT02009449
Legal entity responsible for the study
Armo BioSciences
Funding
ARMO BioSciences
Disclosure
A. Hung, G. Brown: Employee of ARMO BioSciences. P. Van Vlasselaer: Stock, leadership, employee of ARMO BioSciences. M. Oft: Employee of ARMO BioSciences. All other authors have declared no conflicts of interest.